diff --git a/gdb/aarch64-linux-nat.c b/gdb/aarch64-linux-nat.c
index 1919241466..058ee4365d 100644
--- a/gdb/aarch64-linux-nat.c
+++ b/gdb/aarch64-linux-nat.c
@@ -67,9 +67,9 @@ public:
 			 struct expression *) override;
   int remove_watchpoint (CORE_ADDR, int, enum target_hw_bp_type,
 			 struct expression *) override;
-  int stopped_by_watchpoint () override;
-  int stopped_data_address (CORE_ADDR *) override;
-  int watchpoint_addr_within_range (CORE_ADDR, CORE_ADDR, int) override;
+  bool stopped_by_watchpoint () override;
+  bool stopped_data_address (CORE_ADDR *) override;
+  bool watchpoint_addr_within_range (CORE_ADDR, CORE_ADDR, int) override;
 
   int can_do_single_step () override;
 
@@ -733,7 +733,7 @@ aarch64_linux_nat_target::region_ok_for_hw_watchpoint (CORE_ADDR addr, int len)
 
 /* Implement the "stopped_data_address" target_ops method.  */
 
-int
+bool
 aarch64_linux_nat_target::stopped_data_address (CORE_ADDR *addr_p)
 {
   siginfo_t siginfo;
@@ -741,12 +741,12 @@ aarch64_linux_nat_target::stopped_data_address (CORE_ADDR *addr_p)
   struct aarch64_debug_reg_state *state;
 
   if (!linux_nat_get_siginfo (inferior_ptid, &siginfo))
-    return 0;
+    return false;
 
   /* This must be a hardware breakpoint.  */
   if (siginfo.si_signo != SIGTRAP
       || (siginfo.si_code & 0xffff) != TRAP_HWBKPT)
-    return 0;
+    return false;
 
   /* Check if the address matches any watched address.  */
   state = aarch64_get_debug_reg_state (ptid_get_pid (inferior_ptid));
@@ -762,16 +762,16 @@ aarch64_linux_nat_target::stopped_data_address (CORE_ADDR *addr_p)
 	  && addr_trap < addr_watch + len)
 	{
 	  *addr_p = addr_trap;
-	  return 1;
+	  return true;
 	}
     }
 
-  return 0;
+  return false;
 }
 
 /* Implement the "stopped_by_watchpoint" target_ops method.  */
 
-int
+bool
 aarch64_linux_nat_target::stopped_by_watchpoint ()
 {
   CORE_ADDR addr;
@@ -781,7 +781,7 @@ aarch64_linux_nat_target::stopped_by_watchpoint ()
 
 /* Implement the "watchpoint_addr_within_range" target_ops method.  */
 
-int
+bool
 aarch64_linux_nat_target::watchpoint_addr_within_range (CORE_ADDR addr,
 							CORE_ADDR start, int length)
 {
diff --git a/gdb/aix-thread.c b/gdb/aix-thread.c
index 3727336fcb..410fb55e72 100644
--- a/gdb/aix-thread.c
+++ b/gdb/aix-thread.c
@@ -137,7 +137,7 @@ public:
 
   void mourn_inferior () override;
 
-  int thread_alive (ptid_t ptid) override;
+  bool thread_alive (ptid_t ptid) override;
 
   const char *pid_to_str (ptid_t) override;
 
@@ -1762,7 +1762,7 @@ aix_thread_target::mourn_inferior ()
 
 /* Return whether thread PID is still valid.  */
 
-int
+bool
 aix_thread_target::thread_alive (ptid_t ptid)
 {
   struct target_ops *beneath = find_target_beneath (this);
diff --git a/gdb/arm-linux-nat.c b/gdb/arm-linux-nat.c
index 75d89f284e..c66c65f505 100644
--- a/gdb/arm-linux-nat.c
+++ b/gdb/arm-linux-nat.c
@@ -87,11 +87,11 @@ public:
 
   int remove_watchpoint (CORE_ADDR, int, enum target_hw_bp_type,
 			 struct expression *) override;
-  int stopped_by_watchpoint () override;
+  bool stopped_by_watchpoint () override;
 
-  int stopped_data_address (CORE_ADDR *) override;
+  bool stopped_data_address (CORE_ADDR *) override;
 
-  int watchpoint_addr_within_range (CORE_ADDR, CORE_ADDR, int) override;
+  bool watchpoint_addr_within_range (CORE_ADDR, CORE_ADDR, int) override;
 
   const struct target_desc *read_description () override;
 };
@@ -1162,19 +1162,19 @@ arm_linux_nat_target::remove_watchpoint (CORE_ADDR addr,
 }
 
 /* What was the data address the target was stopped on accessing.  */
-int
+bool
 arm_linux_nat_target::stopped_data_address (CORE_ADDR *addr_p)
 {
   siginfo_t siginfo;
   int slot;
 
   if (!linux_nat_get_siginfo (inferior_ptid, &siginfo))
-    return 0;
+    return false;
 
   /* This must be a hardware breakpoint.  */
   if (siginfo.si_signo != SIGTRAP
       || (siginfo.si_code & 0xffff) != 0x0004 /* TRAP_HWBKPT */)
-    return 0;
+    return false;
 
   /* We must be able to set hardware watchpoints.  */
   if (arm_linux_get_hw_watchpoint_count () == 0)
@@ -1185,21 +1185,21 @@ arm_linux_nat_target::stopped_data_address (CORE_ADDR *addr_p)
   /* If we are in a positive slot then we're looking at a breakpoint and not
      a watchpoint.  */
   if (slot >= 0)
-    return 0;
+    return false;
 
   *addr_p = (CORE_ADDR) (uintptr_t) siginfo.si_addr;
-  return 1;
+  return true;
 }
 
 /* Has the target been stopped by hitting a watchpoint?  */
-int
+bool
 arm_linux_nat_target::stopped_by_watchpoint ()
 {
   CORE_ADDR addr;
   return stopped_data_address (&addr);
 }
 
-int
+bool
 arm_linux_nat_target::watchpoint_addr_within_range (CORE_ADDR addr,
 						    CORE_ADDR start,
 						    int length)
diff --git a/gdb/breakpoint.c b/gdb/breakpoint.c
index a5287128d0..5098aed7e1 100644
--- a/gdb/breakpoint.c
+++ b/gdb/breakpoint.c
@@ -4733,7 +4733,7 @@ bpstats::bpstats ()
 int
 watchpoints_triggered (struct target_waitstatus *ws)
 {
-  int stopped_by_watchpoint = target_stopped_by_watchpoint ();
+  bool stopped_by_watchpoint = target_stopped_by_watchpoint ();
   CORE_ADDR addr;
   struct breakpoint *b;
 
diff --git a/gdb/bsd-kvm.c b/gdb/bsd-kvm.c
index f6b7ad15db..804cddb927 100644
--- a/gdb/bsd-kvm.c
+++ b/gdb/bsd-kvm.c
@@ -93,12 +93,12 @@ Optionally specify the filename of a core dump.");
 					ULONGEST *xfered_len) override;
 
   void files_info () override;
-  int thread_alive (ptid_t ptid) override;
+  bool thread_alive (ptid_t ptid) override;
   const char *pid_to_str (ptid_t) override;
 
-  int has_memory () override { return 1; }
-  int has_stack () override { return 1; }
-  int has_registers () override { return 1; }
+  bool has_memory () override { return true; }
+  bool has_stack () override { return true; }
+  bool has_registers () override { return true; }
 };
 
 /* Target ops for libkvm interface.  */
@@ -364,10 +364,10 @@ bsd_kvm_pcb_cmd (const char *arg, int fromtty)
   print_stack_frame (get_selected_frame (NULL), 0, SRC_AND_LOC, 1);
 }
 
-int
+bool
 bsd_kvm_target::thread_alive (ptid_t ptid)
 {
-  return 1;
+  return true;
 }
 
 const char *
diff --git a/gdb/bsd-uthread.c b/gdb/bsd-uthread.c
index 19d49c76f9..efcec1e396 100644
--- a/gdb/bsd-uthread.c
+++ b/gdb/bsd-uthread.c
@@ -57,7 +57,7 @@ struct bsd_uthread_target final : public target_ops
   ptid_t wait (ptid_t, struct target_waitstatus *, int) override;
   void resume (ptid_t, int, enum gdb_signal) override;
 
-  int thread_alive (ptid_t ptid) override;
+  bool thread_alive (ptid_t ptid) override;
 
   void update_thread_list () override;
 
@@ -437,7 +437,7 @@ bsd_uthread_target::resume (ptid_t ptid, int step, enum gdb_signal sig)
   beneath->resume (ptid, step, sig);
 }
 
-int
+bool
 bsd_uthread_target::thread_alive (ptid_t ptid)
 {
   enum bfd_endian byte_order = gdbarch_byte_order (target_gdbarch ());
@@ -453,7 +453,7 @@ bsd_uthread_target::thread_alive (ptid_t ptid)
 
       state = read_memory_unsigned_integer (addr + offset, 4, byte_order);
       if (state == BSD_UTHREAD_PS_DEAD)
-	return 0;
+	return false;
     }
 
   return beneath->thread_alive (ptid);
diff --git a/gdb/corelow.c b/gdb/corelow.c
index f7202f75e3..e7d9a7ed51 100644
--- a/gdb/corelow.c
+++ b/gdb/corelow.c
@@ -83,16 +83,16 @@ Use a core file as a target.  Specify the filename of the core file.");
 					ULONGEST *xfered_len) override;
   void files_info () override;
 
-  int thread_alive (ptid_t ptid) override;
+  bool thread_alive (ptid_t ptid) override;
   const struct target_desc *read_description () override;
 
   const char *pid_to_str (ptid_t) override;
 
   const char *thread_name (struct thread_info *) override;
 
-  int has_memory () override;
-  int has_stack () override;
-  int has_registers () override;
+  bool has_memory () override;
+  bool has_stack () override;
+  bool has_registers () override;
   bool info_proc (const char *, enum info_proc_what) override;
 };
 
@@ -922,10 +922,10 @@ core_target::xfer_partial (enum target_object object, const char *annex,
    to appear in an "info thread" command, which is quite a useful
    behaviour.
  */
-int
+bool
 core_target::thread_alive (ptid_t ptid)
 {
-  return 1;
+  return true;
 }
 
 /* Ask the current architecture what it knows about this core file.
@@ -989,19 +989,19 @@ core_target::thread_name (struct thread_info *thr)
   return NULL;
 }
 
-int
+bool
 core_target::has_memory ()
 {
   return (core_bfd != NULL);
 }
 
-int
+bool
 core_target::has_stack ()
 {
   return (core_bfd != NULL);
 }
 
-int
+bool
 core_target::has_registers ()
 {
   return (core_bfd != NULL);
diff --git a/gdb/ctf.c b/gdb/ctf.c
index b09cebbf07..90d6f6c025 100644
--- a/gdb/ctf.c
+++ b/gdb/ctf.c
@@ -62,7 +62,7 @@ Specify the filename of the CTF directory.");
   void files_info () override;
   int trace_find (enum trace_find_type type, int num,
 			  CORE_ADDR addr1, CORE_ADDR addr2, int *tpp) override;
-  int get_trace_state_variable_value (int tsv, LONGEST *val) override;
+  bool get_trace_state_variable_value (int tsv, LONGEST *val) override;
   traceframe_info_up traceframe_info () override;
 };
 
@@ -1430,11 +1430,11 @@ ctf_target::xfer_partial (enum target_object object,
    trace variable is found, set the value of it to *VAL and return
    true, otherwise return false.  */
 
-int
+bool
 ctf_target::get_trace_state_variable_value (int tsvnum, LONGEST *val)
 {
   struct bt_iter_pos *pos;
-  int found = 0;
+  bool found = false;
 
   gdb_assert (ctf_iter != NULL);
   /* Save the current position.  */
@@ -1465,7 +1465,7 @@ ctf_target::get_trace_state_variable_value (int tsvnum, LONGEST *val)
 	      def = bt_ctf_get_field (event, scope, "val");
 	      *val = bt_ctf_get_uint64 (def);
 
-	      found = 1;
+	      found = true;
 	    }
 	}
 
diff --git a/gdb/darwin-nat.c b/gdb/darwin-nat.c
index 919643145a..8af542863a 100644
--- a/gdb/darwin-nat.c
+++ b/gdb/darwin-nat.c
@@ -1959,10 +1959,10 @@ darwin_nat_target::pid_to_str (ptid_t ptid)
   return normal_pid_to_str (ptid);
 }
 
-int
+bool
 darwin_nat_target::thread_alive (ptid_t ptid)
 {
-  return 1;
+  return true;
 }
 
 /* If RDADDR is not NULL, read inferior task's LEN bytes from ADDR and
@@ -2306,10 +2306,10 @@ darwin_nat_target::get_ada_task_ptid (long lwp, long thread)
     return null_ptid;
 }
 
-int
+bool
 darwin_nat_target::supports_multi_process ()
 {
-  return 1;
+  return true;
 }
 
 void
diff --git a/gdb/darwin-nat.h b/gdb/darwin-nat.h
index d4a06d9c27..9d45bdabe8 100644
--- a/gdb/darwin-nat.h
+++ b/gdb/darwin-nat.h
@@ -43,7 +43,7 @@ class darwin_nat_target : public inf_child_target
 
   void resume (ptid_t, int , enum gdb_signal) override;
 
-  int thread_alive (ptid_t ptid) override;
+  bool thread_alive (ptid_t ptid) override;
 
   const char *pid_to_str (ptid_t) override;
 
@@ -56,7 +56,7 @@ class darwin_nat_target : public inf_child_target
 					ULONGEST offset, ULONGEST len,
 					ULONGEST *xfered_len) override;
 
-  int supports_multi_process () override;
+  bool supports_multi_process () override;
 
   ptid_t get_ada_task_ptid (long lwp, long thread) override;
 };
diff --git a/gdb/exec.c b/gdb/exec.c
index 14d0668591..4c71abd35f 100644
--- a/gdb/exec.c
+++ b/gdb/exec.c
@@ -80,7 +80,7 @@ Specify the filename of the executable file.");
   struct target_section_table *get_section_table () override;
   void files_info () override;
 
-  int has_memory () override;
+  bool has_memory () override;
   char *make_corefile_notes (bfd *, int *) override;
   int find_memory_regions (find_memory_region_ftype func, void *data) override;
 };
@@ -1031,7 +1031,7 @@ exec_set_section_address (const char *filename, int index, CORE_ADDR address)
     }
 }
 
-int
+bool
 exec_target::has_memory ()
 {
   /* We can provide memory if we have any file/target sections to read
diff --git a/gdb/fbsd-nat.c b/gdb/fbsd-nat.c
index 5324f8b07e..c6f8b802e3 100644
--- a/gdb/fbsd-nat.c
+++ b/gdb/fbsd-nat.c
@@ -813,7 +813,7 @@ show_fbsd_nat_debug (struct ui_file *file, int from_tty,
 
 /* Return true if PTID is still active in the inferior.  */
 
-int
+bool
 fbsd_nat_target::thread_alive (ptid_t ptid)
 {
   if (ptid_lwp_p (ptid))
@@ -822,14 +822,14 @@ fbsd_nat_target::thread_alive (ptid_t ptid)
 
       if (ptrace (PT_LWPINFO, ptid_get_lwp (ptid), (caddr_t) &pl, sizeof pl)
 	  == -1)
-	return 0;
+	return false;
 #ifdef PL_FLAG_EXITED
       if (pl.pl_flags & PL_FLAG_EXITED)
-	return 0;
+	return false;
 #endif
     }
 
-  return 1;
+  return true;
 }
 
 /* Convert PTID to a string.  Returns the string in a static
@@ -1458,14 +1458,14 @@ fbsd_nat_target::wait (ptid_t ptid, struct target_waitstatus *ourstatus,
 #ifdef USE_SIGTRAP_SIGINFO
 /* Implement the "stopped_by_sw_breakpoint" target_ops method.  */
 
-int
+bool
 fbsd_nat_target::stopped_by_sw_breakpoint ()
 {
   struct ptrace_lwpinfo pl;
 
   if (ptrace (PT_LWPINFO, get_ptrace_pid (inferior_ptid), (caddr_t) &pl,
 	      sizeof pl) == -1)
-    return 0;
+    return false;
 
   return ((pl.pl_flags & PL_FLAG_SI)
 	  && pl.pl_siginfo.si_signo == SIGTRAP
@@ -1475,10 +1475,10 @@ fbsd_nat_target::stopped_by_sw_breakpoint ()
 /* Implement the "supports_stopped_by_sw_breakpoint" target_ops
    method.  */
 
-int
+bool
 fbsd_nat_target::supports_stopped_by_sw_breakpoint ()
 {
-  return 1;
+  return true;
 }
 #endif
 
diff --git a/gdb/fbsd-nat.h b/gdb/fbsd-nat.h
index a4418bb8f8..031d7d6d27 100644
--- a/gdb/fbsd-nat.h
+++ b/gdb/fbsd-nat.h
@@ -41,7 +41,7 @@ public:
 #endif
 
 #ifdef PT_LWPINFO
-  int thread_alive (ptid_t ptid) override;
+  bool thread_alive (ptid_t ptid) override;
   const char *pid_to_str (ptid_t) override;
 
 #ifdef HAVE_STRUCT_PTRACE_LWPINFO_PL_TDNAME
@@ -61,8 +61,8 @@ public:
   void post_attach (int) override;
 
 #ifdef USE_SIGTRAP_SIGINFO
-  int supports_stopped_by_sw_breakpoint () override;
-  int stopped_by_sw_breakpoint () override;
+  bool supports_stopped_by_sw_breakpoint () override;
+  bool stopped_by_sw_breakpoint () override;
 #endif
 
 #ifdef TDP_RFPPWAIT
diff --git a/gdb/gnu-nat.c b/gdb/gnu-nat.c
index 89df55fdde..c7a40400fc 100644
--- a/gdb/gnu-nat.c
+++ b/gdb/gnu-nat.c
@@ -2288,7 +2288,7 @@ gnu_nat_target::stop (ptid_t ptid)
   error (_("stop target function not implemented"));
 }
 
-int
+bool
 gnu_nat_target::thread_alive (ptid_t ptid)
 {
   inf_update_procs (gnu_current_inf);
diff --git a/gdb/gnu-nat.h b/gdb/gnu-nat.h
index 4189eaf026..f8ec692064 100644
--- a/gdb/gnu-nat.h
+++ b/gdb/gnu-nat.h
@@ -130,7 +130,7 @@ struct gnu_nat_target : public inf_child_target
   void create_inferior (const char *, const std::string &,
 			char **, int) override;
   void mourn_inferior () override;
-  int thread_alive (ptid_t ptid) override;
+  bool thread_alive (ptid_t ptid) override;
   const char *pid_to_str (ptid_t) override;
   void stop (ptid_t) override;
 };
diff --git a/gdb/go32-nat.c b/gdb/go32-nat.c
index dcf60cb3d2..6f6aedea7e 100644
--- a/gdb/go32-nat.c
+++ b/gdb/go32-nat.c
@@ -375,7 +375,7 @@ class go32_nat_target : public x86_nat_target<inf_child_target>
 
   void mourn_inferior () override;
 
-  int thread_alive (ptid_t ptid) override;
+  bool thread_alive (ptid_t ptid) override;
 
   const char *pid_to_str (ptid_t) override;
 };
@@ -987,7 +987,7 @@ go32_nat_target::pass_ctrlc ()
 {
 }
 
-int
+bool
 go32_nat_target::thread_alive (ptid_t ptid)
 {
   return !ptid_equal (ptid, null_ptid);
diff --git a/gdb/ia64-linux-nat.c b/gdb/ia64-linux-nat.c
index 2aa66a5682..9435bcf1ab 100644
--- a/gdb/ia64-linux-nat.c
+++ b/gdb/ia64-linux-nat.c
@@ -70,11 +70,11 @@ public:
      has determined that a hardware watchpoint has indeed been hit.
      The CPU will then be able to execute one instruction without
      triggering a watchpoint.  */
-  int have_steppable_watchpoint () { return 1; }
+  bool have_steppable_watchpoint () { return 1; }
 
   int can_use_hw_breakpoint (enum bptype, int, int) override;
-  int stopped_by_watchpoint () override;
-  int stopped_data_address (CORE_ADDR *) override;
+  bool stopped_by_watchpoint () override;
+  bool stopped_data_address (CORE_ADDR *) override;
   int insert_watchpoint (CORE_ADDR, int, enum target_hw_bp_type,
 			 struct expression *) override;
   int remove_watchpoint (CORE_ADDR, int, enum target_hw_bp_type,
@@ -688,7 +688,7 @@ ia64_linux_new_thread (struct lwp_info *lp)
     enable_watchpoints_in_psr (lp->ptid);
 }
 
-int
+bool
 ia64_linux_nat_target::stopped_data_address (CORE_ADDR *addr_p)
 {
   CORE_ADDR psr;
@@ -696,11 +696,11 @@ ia64_linux_nat_target::stopped_data_address (CORE_ADDR *addr_p)
   struct regcache *regcache = get_current_regcache ();
 
   if (!linux_nat_get_siginfo (inferior_ptid, &siginfo))
-    return 0;
+    return false;
 
   if (siginfo.si_signo != SIGTRAP
       || (siginfo.si_code & 0xffff) != 0x0004 /* TRAP_HWBKPT */)
-    return 0;
+    return false;
 
   regcache_cooked_read_unsigned (regcache, IA64_PSR_REGNUM, &psr);
   psr |= IA64_PSR_DD;	/* Set the dd bit - this will disable the watchpoint
@@ -708,10 +708,10 @@ ia64_linux_nat_target::stopped_data_address (CORE_ADDR *addr_p)
   regcache_cooked_write_unsigned (regcache, IA64_PSR_REGNUM, psr);
 
   *addr_p = (CORE_ADDR) siginfo.si_addr;
-  return 1;
+  return true;
 }
 
-int
+bool
 ia64_linux_nat_target::stopped_by_watchpoint ()
 {
   CORE_ADDR addr;
diff --git a/gdb/inf-child.c b/gdb/inf-child.c
index 7b2f2a25a2..8e5ebfa2c2 100644
--- a/gdb/inf-child.c
+++ b/gdb/inf-child.c
@@ -200,10 +200,10 @@ inf_child_target::post_startup_inferior (ptid_t ptid)
      operation by a debugger.  */
 }
 
-int
+bool
 inf_child_target::can_run ()
 {
-  return 1;
+  return true;
 }
 
 bool
@@ -226,31 +226,31 @@ inf_child_target::pid_to_exec_file (int pid)
   return NULL;
 }
 
-int
+bool
 inf_child_target::has_all_memory ()
 {
   return default_child_has_all_memory ();
 }
 
-int
+bool
 inf_child_target::has_memory ()
 {
   return default_child_has_memory ();
 }
 
-int
+bool
 inf_child_target::has_stack ()
 {
   return default_child_has_stack ();
 }
 
-int
+bool
 inf_child_target::has_registers ()
 {
   return default_child_has_registers ();
 }
 
-int
+bool
 inf_child_target::has_execution (ptid_t ptid)
 {
   return default_child_has_execution (ptid);
@@ -404,19 +404,19 @@ inf_child_target::fileio_readlink (struct inferior *inf, const char *filename,
 #endif
 }
 
-int
-inf_child_target::use_agent (int use)
+bool
+inf_child_target::use_agent (bool use)
 {
   if (agent_loaded_p ())
     {
       ::use_agent = use;
-      return 1;
+      return true;
     }
   else
-    return 0;
+    return false;
 }
 
-int
+bool
 inf_child_target::can_use_agent ()
 {
   return agent_loaded_p ();
diff --git a/gdb/inf-child.h b/gdb/inf-child.h
index 1b9c8c53ae..755c462fb8 100644
--- a/gdb/inf-child.h
+++ b/gdb/inf-child.h
@@ -65,7 +65,7 @@ public:
 
   void mourn_inferior () override;
 
-  int can_run () override;
+  bool can_run () override;
 
   bool can_create_inferior () override;
   void create_inferior (const char *, const std::string &,
@@ -78,16 +78,16 @@ public:
 
   /* We must default these because they must be implemented by any
      target that can run.  */
-  int can_async_p ()  override { return 0; }
-  int supports_non_stop ()  override { return 0; }
+  bool can_async_p ()  override { return false; }
+  bool supports_non_stop ()  override { return false; }
 
   char *pid_to_exec_file (int pid) override;
 
-  int has_all_memory () override;
-  int has_memory () override;
-  int has_stack () override;
-  int has_registers () override;
-  int has_execution (ptid_t) override;
+  bool has_all_memory () override;
+  bool has_memory () override;
+  bool has_stack () override;
+  bool has_registers () override;
+  bool has_execution (ptid_t) override;
 
   int fileio_open (struct inferior *inf, const char *filename,
 		   int flags, int mode, int warn_if_slow,
@@ -104,9 +104,9 @@ public:
   gdb::optional<std::string> fileio_readlink (struct inferior *inf,
 					      const char *filename,
 					      int *target_errno) override;
-  int use_agent (int use) override;
+  bool use_agent (bool use) override;
 
-  int can_use_agent () override;
+  bool can_use_agent () override;
 
 protected:
   /* Unpush the target if it wasn't explicitly open with "target native"
diff --git a/gdb/inf-ptrace.c b/gdb/inf-ptrace.c
index 8f5a378353..78b57730d2 100644
--- a/gdb/inf-ptrace.c
+++ b/gdb/inf-ptrace.c
@@ -607,7 +607,7 @@ inf_ptrace_target::xfer_partial (enum target_object object,
 
 /* Return non-zero if the thread specified by PTID is alive.  */
 
-int
+bool
 inf_ptrace_target::thread_alive (ptid_t ptid)
 {
   /* ??? Is kill the right way to do this?  */
diff --git a/gdb/inf-ptrace.h b/gdb/inf-ptrace.h
index bd9b609ab4..de284f9536 100644
--- a/gdb/inf-ptrace.h
+++ b/gdb/inf-ptrace.h
@@ -57,7 +57,7 @@ struct inf_ptrace_target : public inf_child_target
 
   void mourn_inferior () override;
 
-  int thread_alive (ptid_t ptid) override;
+  bool thread_alive (ptid_t ptid) override;
 
   const char *pid_to_str (ptid_t) override;
 
diff --git a/gdb/linux-nat.c b/gdb/linux-nat.c
index bfc2e46ed6..701a7db05b 100644
--- a/gdb/linux-nat.c
+++ b/gdb/linux-nat.c
@@ -2474,7 +2474,7 @@ check_stopped_by_watchpoint (struct lwp_info *lp)
 
 /* Returns true if the LWP had stopped for a watchpoint.  */
 
-int
+bool
 linux_nat_target::stopped_by_watchpoint ()
 {
   struct lwp_info *lp = find_lwp_pid (inferior_ptid);
@@ -2484,7 +2484,7 @@ linux_nat_target::stopped_by_watchpoint ()
   return lp->stop_reason == TARGET_STOPPED_BY_WATCHPOINT;
 }
 
-int
+bool
 linux_nat_target::stopped_data_address (CORE_ADDR *addr_p)
 {
   struct lwp_info *lp = find_lwp_pid (inferior_ptid);
@@ -2835,7 +2835,7 @@ save_stop_reason (struct lwp_info *lp)
 
 /* Returns true if the LWP had stopped for a software breakpoint.  */
 
-int
+bool
 linux_nat_target::stopped_by_sw_breakpoint ()
 {
   struct lwp_info *lp = find_lwp_pid (inferior_ptid);
@@ -2847,7 +2847,7 @@ linux_nat_target::stopped_by_sw_breakpoint ()
 
 /* Implement the supports_stopped_by_sw_breakpoint method.  */
 
-int
+bool
 linux_nat_target::supports_stopped_by_sw_breakpoint ()
 {
   return USE_SIGTRAP_SIGINFO;
@@ -2856,7 +2856,7 @@ linux_nat_target::supports_stopped_by_sw_breakpoint ()
 /* Returns true if the LWP had stopped for a hardware
    breakpoint/watchpoint.  */
 
-int
+bool
 linux_nat_target::stopped_by_hw_breakpoint ()
 {
   struct lwp_info *lp = find_lwp_pid (inferior_ptid);
@@ -2868,7 +2868,7 @@ linux_nat_target::stopped_by_hw_breakpoint ()
 
 /* Implement the supports_stopped_by_hw_breakpoint method.  */
 
-int
+bool
 linux_nat_target::supports_stopped_by_hw_breakpoint ()
 {
   return USE_SIGTRAP_SIGINFO;
@@ -3940,7 +3940,7 @@ linux_nat_target::xfer_partial (enum target_object object,
 					  offset, len, xfered_len);
 }
 
-int
+bool
 linux_nat_target::thread_alive (ptid_t ptid)
 {
   /* As long as a PTID is in lwp list, consider it alive.  */
@@ -4322,7 +4322,7 @@ linux_nat_target::static_tracepoint_markers_by_strid (const char *strid)
 
 /* target_is_async_p implementation.  */
 
-int
+bool
 linux_nat_target::is_async_p ()
 {
   return linux_is_async_p ();
@@ -4330,7 +4330,7 @@ linux_nat_target::is_async_p ()
 
 /* target_can_async_p implementation.  */
 
-int
+bool
 linux_nat_target::can_async_p ()
 {
   /* We're always async, unless the user explicitly prevented it with the
@@ -4338,7 +4338,7 @@ linux_nat_target::can_async_p ()
   return target_async_permitted;
 }
 
-int
+bool
 linux_nat_target::supports_non_stop ()
 {
   return 1;
@@ -4346,7 +4346,7 @@ linux_nat_target::supports_non_stop ()
 
 /* to_always_non_stop_p implementation.  */
 
-int
+bool
 linux_nat_target::always_non_stop_p ()
 {
   return 1;
@@ -4357,13 +4357,13 @@ linux_nat_target::always_non_stop_p ()
 
 int linux_multi_process = 1;
 
-int
+bool
 linux_nat_target::supports_multi_process ()
 {
   return linux_multi_process;
 }
 
-int
+bool
 linux_nat_target::supports_disable_randomization ()
 {
 #ifdef HAVE_PERSONALITY
@@ -4574,13 +4574,13 @@ linux_nat_target::core_of_thread (ptid_t ptid)
 
 /* Implementation of to_filesystem_is_local.  */
 
-int
+bool
 linux_nat_target::filesystem_is_local ()
 {
   struct inferior *inf = current_inferior ();
 
   if (inf->fake_pid_p || inf->pid == 0)
-    return 1;
+    return true;
 
   return linux_ns_same (inf->pid, LINUX_NS_MNT);
 }
diff --git a/gdb/linux-nat.h b/gdb/linux-nat.h
index da5357a21e..fbee35e9b6 100644
--- a/gdb/linux-nat.h
+++ b/gdb/linux-nat.h
@@ -57,7 +57,7 @@ public:
   void kill () override;
 
   void mourn_inferior () override;
-  int thread_alive (ptid_t ptid) override;
+  bool thread_alive (ptid_t ptid) override;
 
   void update_thread_list () override;
 
@@ -67,23 +67,23 @@ public:
 
   struct address_space *thread_address_space (ptid_t) override;
 
-  int stopped_by_watchpoint () override;
+  bool stopped_by_watchpoint () override;
 
-  int stopped_data_address (CORE_ADDR *) override;
+  bool stopped_data_address (CORE_ADDR *) override;
 
-  int stopped_by_sw_breakpoint () override;
-  int supports_stopped_by_sw_breakpoint () override;
+  bool stopped_by_sw_breakpoint () override;
+  bool supports_stopped_by_sw_breakpoint () override;
 
-  int stopped_by_hw_breakpoint () override;
-  int supports_stopped_by_hw_breakpoint () override;
+  bool stopped_by_hw_breakpoint () override;
+  bool supports_stopped_by_hw_breakpoint () override;
 
   void thread_events (int) override;
 
-  int can_async_p () override;
-  int is_async_p () override;
+  bool can_async_p () override;
+  bool is_async_p () override;
 
-  int supports_non_stop () override;
-  int always_non_stop_p () override;
+  bool supports_non_stop () override;
+  bool always_non_stop_p () override;
 
   void async (int) override;
 
@@ -91,13 +91,13 @@ public:
 
   void stop (ptid_t) override;
 
-  int supports_multi_process () override;
+  bool supports_multi_process () override;
 
-  int supports_disable_randomization () override;
+  bool supports_disable_randomization () override;
 
   int core_of_thread (ptid_t ptid) override;
 
-  int filesystem_is_local () override;
+  bool filesystem_is_local () override;
 
   int fileio_open (struct inferior *inf, const char *filename,
 		   int flags, int mode, int warn_if_slow,
@@ -140,11 +140,11 @@ public:
   virtual void low_resume (ptid_t ptid, int step, enum gdb_signal sig)
   { inf_ptrace_target::resume (ptid, step, sig); }
 
-  virtual int low_stopped_by_watchpoint ()
-  { return 0; }
+  virtual bool low_stopped_by_watchpoint ()
+  { return false; }
 
-  virtual int low_stopped_data_address (CORE_ADDR *addr_p)
-  { return 0; }
+  virtual bool low_stopped_data_address (CORE_ADDR *addr_p)
+  { return false; }
 };
 
 /* The final/concrete instance.  */
diff --git a/gdb/mips-linux-nat.c b/gdb/mips-linux-nat.c
index 1cd97d53c7..0659c2e90d 100644
--- a/gdb/mips-linux-nat.c
+++ b/gdb/mips-linux-nat.c
@@ -59,9 +59,9 @@ public:
   int insert_watchpoint (CORE_ADDR, int, enum target_hw_bp_type,
 			 struct expression *) override;
 
-  int stopped_by_watchpoint () override;
+  bool stopped_by_watchpoint () override;
 
-  int stopped_data_address (CORE_ADDR *) override;
+  bool stopped_data_address (CORE_ADDR *) override;
 
   int region_ok_for_hw_watchpoint (CORE_ADDR, int) override;
 
@@ -572,7 +572,7 @@ mips_linux_nat_target::can_use_hw_breakpoint (enum bptype type,
    stopped by watchpoint.  The watchhi R and W bits indicate the watch
    register triggered.  */
 
-int
+bool
 mips_linux_nat_target::stopped_by_watchpoint ()
 {
   int n;
@@ -581,27 +581,27 @@ mips_linux_nat_target::stopped_by_watchpoint ()
   if (!mips_linux_read_watch_registers (ptid_get_lwp (inferior_ptid),
 					&watch_readback,
 					&watch_readback_valid, 1))
-    return 0;
+    return false;
 
   num_valid = mips_linux_watch_get_num_valid (&watch_readback);
 
   for (n = 0; n < MAX_DEBUG_REGISTER && n < num_valid; n++)
     if (mips_linux_watch_get_watchhi (&watch_readback, n) & (R_MASK | W_MASK))
-      return 1;
+      return true;
 
-  return 0;
+  return false;
 }
 
 /* Target to_stopped_data_address implementation.  Set the address
    where the watch triggered (if known).  Return 1 if the address was
    known.  */
 
-int
+bool
 mips_linux_nat_target::stopped_data_address (CORE_ADDR *paddr)
 {
   /* On mips we don't know the low order 3 bits of the data address,
      so we must return false.  */
-  return 0;
+  return false;
 }
 
 /* Target to_region_ok_for_hw_watchpoint implementation.  Return 1 if
diff --git a/gdb/nto-procfs.c b/gdb/nto-procfs.c
index 1ca4bac336..f3ba877840 100644
--- a/gdb/nto-procfs.c
+++ b/gdb/nto-procfs.c
@@ -100,7 +100,7 @@ struct nto_procfs_target : public inf_child_target
   int remove_watchpoint (CORE_ADDR, int, enum target_hw_bp_type,
 			 struct expression *) override;
 
-  int stopped_by_watchpoint () override;
+  bool stopped_by_watchpoint () override;
 
   void kill () override;
 
@@ -111,7 +111,7 @@ struct nto_procfs_target : public inf_child_target
 
   void pass_signals (int, unsigned char *) override;
 
-  int thread_alive (ptid_t ptid) override;
+  bool thread_alive (ptid_t ptid) override;
 
   void update_thread_list () override;
 
@@ -297,8 +297,9 @@ procfs_set_thread (ptid_t ptid)
   devctl (ctl_fd, DCMD_PROC_CURTHREAD, &tid, sizeof (tid), 0);
 }
 
-/*  Return nonzero if the thread TH is still alive.  */
-int
+/*  Return true if the thread TH is still alive.  */
+
+bool
 nto_procfs_target::thread_alive (ptid_t ptid)
 {
   pid_t tid;
@@ -310,12 +311,12 @@ nto_procfs_target::thread_alive (ptid_t ptid)
   pid = ptid_get_pid (ptid);
 
   if (kill (pid, 0) == -1)
-    return 0;
+    return false;
 
   status.tid = tid;
   if ((err = devctl (ctl_fd, DCMD_PROC_TIDSTATUS,
 		     &status, sizeof (status), 0)) != EOK)
-    return 0;
+    return false;
 
   /* Thread is alive or dead but not yet joined,
      or dead and there is an alive (or dead unjoined) thread with
@@ -1583,7 +1584,7 @@ procfs_hw_watchpoint (int addr, int len, enum target_hw_bp_type type)
   return 0;
 }
 
-int
+bool
 nto_procfs_target::can_use_hw_breakpoint (enum bptype type,
 					  int cnt, int othertype)
 {
@@ -1606,7 +1607,7 @@ nto_procfs_target::insert_hw_watchpoint (CORE_ADDR addr, int len,
   return procfs_hw_watchpoint (addr, len, type);
 }
 
-int
+bool
 nto_procfs_target::stopped_by_watchpoint ()
 {
   /* NOTE: nto_stopped_by_watchpoint will be called ONLY while we are
diff --git a/gdb/ppc-linux-nat.c b/gdb/ppc-linux-nat.c
index c9f0f9d48d..7362bee4ef 100644
--- a/gdb/ppc-linux-nat.c
+++ b/gdb/ppc-linux-nat.c
@@ -296,13 +296,13 @@ struct ppc_linux_nat_target final : public linux_nat_target
   int remove_mask_watchpoint (CORE_ADDR, CORE_ADDR, enum target_hw_bp_type)
     override;
 
-  int stopped_by_watchpoint () override;
+  bool stopped_by_watchpoint () override;
 
-  int stopped_data_address (CORE_ADDR *) override;
+  bool stopped_data_address (CORE_ADDR *) override;
 
-  int watchpoint_addr_within_range (CORE_ADDR, CORE_ADDR, int) override;
+  bool watchpoint_addr_within_range (CORE_ADDR, CORE_ADDR, int) override;
 
-  int can_accel_watchpoint_condition (CORE_ADDR, int, int, struct expression *)
+  bool can_accel_watchpoint_condition (CORE_ADDR, int, int, struct expression *)
     override;
 
   int masked_watch_num_registers (CORE_ADDR, CORE_ADDR) override;
@@ -1986,7 +1986,7 @@ check_condition (CORE_ADDR watch_addr, struct expression *cond,
 /* Return non-zero if the target is capable of using hardware to evaluate
    the condition expression, thus only triggering the watchpoint when it is
    true.  */
-int
+bool
 ppc_linux_nat_target::can_accel_watchpoint_condition (CORE_ADDR addr, int len,
 						      int rw,
 						      struct expression *cond)
@@ -2222,17 +2222,17 @@ ppc_linux_thread_exit (struct thread_info *tp, int silent)
   xfree (t);
 }
 
-int
+bool
 ppc_linux_nat_target::stopped_data_address (CORE_ADDR *addr_p)
 {
   siginfo_t siginfo;
 
   if (!linux_nat_get_siginfo (inferior_ptid, &siginfo))
-    return 0;
+    return false;
 
   if (siginfo.si_signo != SIGTRAP
       || (siginfo.si_code & 0xffff) != 0x0004 /* TRAP_HWBKPT */)
-    return 0;
+    return false;
 
   if (have_ptrace_hwdebug_interface ())
     {
@@ -2253,22 +2253,22 @@ ppc_linux_nat_target::stopped_data_address (CORE_ADDR *addr_p)
 	   if (hw_breaks[i].hw_break && hw_breaks[i].slot == slot
 	       && hw_breaks[i].hw_break->trigger_type
 		    == PPC_BREAKPOINT_TRIGGER_EXECUTE)
-	     return 0;
+	     return false;
 	}
     }
 
   *addr_p = (CORE_ADDR) (uintptr_t) siginfo.si_addr;
-  return 1;
+  return true;
 }
 
-int
+bool
 ppc_linux_nat_target::stopped_by_watchpoint ()
 {
   CORE_ADDR addr;
   return stopped_data_address (&addr);
 }
 
-int
+bool
 ppc_linux_nat_target::watchpoint_addr_within_range (CORE_ADDR addr,
 						    CORE_ADDR start,
 						    int length)
diff --git a/gdb/procfs.c b/gdb/procfs.c
index abae358c44..749b2b4833 100644
--- a/gdb/procfs.c
+++ b/gdb/procfs.c
@@ -124,7 +124,7 @@ public:
 
   void update_thread_list () override;
 
-  int thread_alive (ptid_t ptid) override;
+  bool thread_alive (ptid_t ptid) override;
 
   const char *pid_to_str (ptid_t) override;
 
@@ -145,7 +145,7 @@ public:
     override;
 #endif
 
-  int stopped_by_watchpoint () override;
+  bool stopped_by_watchpoint () override;
 
   int insert_watchpoint (CORE_ADDR, int, enum target_hw_bp_type,
 			 struct expression *) override;
@@ -156,7 +156,7 @@ public:
   int region_ok_for_hw_watchpoint (CORE_ADDR, int) override;
 
   int can_use_hw_breakpoint (enum bptype, int, int) override;
-  int stopped_data_address (CORE_ADDR *) override;
+  bool stopped_data_address (CORE_ADDR *) override;
 };
 
 static procfs_target the_procfs_target;
@@ -3179,7 +3179,7 @@ procfs_target::update_thread_list ()
    really seem to be doing his job.  Got to investigate how to tell
    when a thread is really gone.  */
 
-int
+bool
 procfs_target::thread_alive (ptid_t ptid)
 {
   int proc, thread;
@@ -3189,18 +3189,18 @@ procfs_target::thread_alive (ptid_t ptid)
   thread  = ptid_get_lwp (ptid);
   /* If I don't know it, it ain't alive!  */
   if ((pi = find_procinfo (proc, thread)) == NULL)
-    return 0;
+    return false;
 
   /* If I can't get its status, it ain't alive!
      What's more, I need to forget about it!  */
   if (!proc_get_status (pi))
     {
       destroy_procinfo (pi);
-      return 0;
+      return false;
     }
   /* I couldn't have got its status if it weren't alive, so it's
      alive.  */
-  return 1;
+  return true;
 }
 
 /* Convert PTID to a string.  Returns the string in a static
@@ -3301,7 +3301,7 @@ procfs_target::can_use_hw_breakpoint (enum bptype type, int cnt, int othertype)
 /* Returns non-zero if process is stopped on a hardware watchpoint
    fault, else returns zero.  */
 
-int
+bool
 procfs_target::stopped_by_watchpoint ()
 {
   procinfo *pi;
@@ -3313,10 +3313,10 @@ procfs_target::stopped_by_watchpoint ()
       if (proc_why (pi) == PR_FAULTED)
 	{
 	  if (proc_what (pi) == FLTWATCH)
-	    return 1;
+	    return true;
 	}
     }
-  return 0;
+  return false;
 }
 
 /* Returns 1 if the OS knows the position of the triggered watchpoint,
@@ -3325,7 +3325,7 @@ procfs_target::stopped_by_watchpoint ()
    procfs_stopped_by_watchpoint returned 1, thus no further checks are
    done.  The function also assumes that ADDR is not NULL.  */
 
-int
+bool
 procfs_target::stopped_data_address (CORE_ADDR *addr)
 {
   procinfo *pi;
diff --git a/gdb/ravenscar-thread.c b/gdb/ravenscar-thread.c
index e850ef7507..03cbe3d9e7 100644
--- a/gdb/ravenscar-thread.c
+++ b/gdb/ravenscar-thread.c
@@ -95,15 +95,15 @@ struct ravenscar_thread_target final : public target_ops
 
   void prepare_to_store (struct regcache *) override;
 
-  int stopped_by_sw_breakpoint () override;
+  bool stopped_by_sw_breakpoint () override;
 
-  int stopped_by_hw_breakpoint () override;
+  bool stopped_by_hw_breakpoint () override;
 
-  int stopped_by_watchpoint () override;
+  bool stopped_by_watchpoint () override;
 
-  int stopped_data_address (CORE_ADDR *) override;
+  bool stopped_data_address (CORE_ADDR *) override;
 
-  int thread_alive (ptid_t ptid) override;
+  bool thread_alive (ptid_t ptid) override;
 
   int core_of_thread (ptid_t ptid) override;
 
@@ -117,11 +117,11 @@ struct ravenscar_thread_target final : public target_ops
 
   void mourn_inferior () override;
 
-  int has_all_memory ()  override { return default_child_has_all_memory (); }
-  int has_memory ()  override { return default_child_has_memory (); }
-  int has_stack ()  override { return default_child_has_stack (); }
-  int has_registers ()  override { return default_child_has_registers (); }
-  int has_execution (ptid_t ptid) override
+  bool has_all_memory ()  override { return default_child_has_all_memory (); }
+  bool has_memory ()  override { return default_child_has_memory (); }
+  bool has_stack ()  override { return default_child_has_stack (); }
+  bool has_registers ()  override { return default_child_has_registers (); }
+  bool has_execution (ptid_t ptid) override
   { return default_child_has_execution (ptid); }
 };
 
@@ -396,11 +396,11 @@ ravenscar_thread_target::extra_thread_info (thread_info *tp)
   return "Ravenscar task";
 }
 
-int
+bool
 ravenscar_thread_target::thread_alive (ptid_t ptid)
 {
   /* Ravenscar tasks are non-terminating.  */
-  return 1;
+  return true;
 }
 
 const char *
@@ -475,12 +475,12 @@ ravenscar_thread_target::prepare_to_store (struct regcache *regcache)
 
 /* Implement the to_stopped_by_sw_breakpoint target_ops "method".  */
 
-int
+bool
 ravenscar_thread_target::stopped_by_sw_breakpoint ()
 {
   ptid_t saved_ptid = inferior_ptid;
   struct target_ops *beneath = find_target_beneath (this);
-  int result;
+  bool result;
 
   inferior_ptid = get_base_thread_from_ravenscar_task (saved_ptid);
   result = beneath->stopped_by_sw_breakpoint ();
@@ -490,12 +490,12 @@ ravenscar_thread_target::stopped_by_sw_breakpoint ()
 
 /* Implement the to_stopped_by_hw_breakpoint target_ops "method".  */
 
-int
+bool
 ravenscar_thread_target::stopped_by_hw_breakpoint ()
 {
   ptid_t saved_ptid = inferior_ptid;
   struct target_ops *beneath = find_target_beneath (this);
-  int result;
+  bool result;
 
   inferior_ptid = get_base_thread_from_ravenscar_task (saved_ptid);
   result = beneath->stopped_by_hw_breakpoint ();
@@ -505,12 +505,12 @@ ravenscar_thread_target::stopped_by_hw_breakpoint ()
 
 /* Implement the to_stopped_by_watchpoint target_ops "method".  */
 
-int
+bool
 ravenscar_thread_target::stopped_by_watchpoint ()
 {
   ptid_t saved_ptid = inferior_ptid;
   struct target_ops *beneath = find_target_beneath (this);
-  int result;
+  bool result;
 
   inferior_ptid = get_base_thread_from_ravenscar_task (saved_ptid);
   result = beneath->stopped_by_watchpoint ();
@@ -520,12 +520,12 @@ ravenscar_thread_target::stopped_by_watchpoint ()
 
 /* Implement the to_stopped_data_address target_ops "method".  */
 
-int
+bool
 ravenscar_thread_target::stopped_data_address (CORE_ADDR *addr_p)
 {
   ptid_t saved_ptid = inferior_ptid;
   struct target_ops *beneath = find_target_beneath (this);
-  int result;
+  bool result;
 
   inferior_ptid = get_base_thread_from_ravenscar_task (saved_ptid);
   result = beneath->stopped_data_address (addr_p);
diff --git a/gdb/record-btrace.c b/gdb/record-btrace.c
index cce188e71a..3c1cfb6601 100644
--- a/gdb/record-btrace.c
+++ b/gdb/record-btrace.c
@@ -89,8 +89,8 @@ public:
   void call_history_range (ULONGEST begin, ULONGEST end, record_print_flags flags)
     override;
 
-  int record_is_replaying (ptid_t ptid) override;
-  int record_will_replay (ptid_t ptid, int dir) override;
+  bool record_is_replaying (ptid_t ptid) override;
+  bool record_will_replay (ptid_t ptid, int dir) override;
   void record_stop_replaying () override;
 
   enum target_xfer_status xfer_partial (enum target_object object,
@@ -120,18 +120,18 @@ public:
 
   void stop (ptid_t) override;
   void update_thread_list () override;
-  int thread_alive (ptid_t ptid) override;
+  bool thread_alive (ptid_t ptid) override;
   void goto_record_begin () override;
   void goto_record_end () override;
   void goto_record (ULONGEST insn) override;
 
-  int can_execute_reverse () override;
+  bool can_execute_reverse () override;
 
-  int stopped_by_sw_breakpoint () override;
-  int supports_stopped_by_sw_breakpoint () override;
+  bool stopped_by_sw_breakpoint () override;
+  bool supports_stopped_by_sw_breakpoint () override;
 
-  int stopped_by_hw_breakpoint () override;
-  int supports_stopped_by_hw_breakpoint () override;
+  bool stopped_by_hw_breakpoint () override;
+  bool supports_stopped_by_hw_breakpoint () override;
 
   enum exec_direction_kind execution_direction () override;
   void prepare_to_generate_core () override;
@@ -1359,21 +1359,21 @@ record_btrace_target::record_method (ptid_t ptid)
 
 /* The record_is_replaying method of target record-btrace.  */
 
-int
+bool
 record_btrace_target::record_is_replaying (ptid_t ptid)
 {
   struct thread_info *tp;
 
   ALL_NON_EXITED_THREADS (tp)
     if (ptid_match (tp->ptid, ptid) && btrace_is_replaying (tp))
-      return 1;
+      return true;
 
-  return 0;
+  return false;
 }
 
 /* The record_will_replay method of target record-btrace.  */
 
-int
+bool
 record_btrace_target::record_will_replay (ptid_t ptid, int dir)
 {
   return dir == EXEC_REVERSE || record_is_replaying (ptid);
@@ -2671,15 +2671,15 @@ record_btrace_target::stop (ptid_t ptid)
 
 /* The can_execute_reverse method of target record-btrace.  */
 
-int
+bool
 record_btrace_target::can_execute_reverse ()
 {
-  return 1;
+  return true;
 }
 
 /* The stopped_by_sw_breakpoint method of target record-btrace.  */
 
-int
+bool
 record_btrace_target::stopped_by_sw_breakpoint ()
 {
   if (record_is_replaying (minus_one_ptid))
@@ -2695,18 +2695,18 @@ record_btrace_target::stopped_by_sw_breakpoint ()
 /* The supports_stopped_by_sw_breakpoint method of target
    record-btrace.  */
 
-int
+bool
 record_btrace_target::supports_stopped_by_sw_breakpoint ()
 {
   if (record_is_replaying (minus_one_ptid))
-    return 1;
+    return true;
 
   return this->beneath->supports_stopped_by_sw_breakpoint ();
 }
 
 /* The stopped_by_sw_breakpoint method of target record-btrace.  */
 
-int
+bool
 record_btrace_target::stopped_by_hw_breakpoint ()
 {
   if (record_is_replaying (minus_one_ptid))
@@ -2722,11 +2722,11 @@ record_btrace_target::stopped_by_hw_breakpoint ()
 /* The supports_stopped_by_hw_breakpoint method of target
    record-btrace.  */
 
-int
+bool
 record_btrace_target::supports_stopped_by_hw_breakpoint ()
 {
   if (record_is_replaying (minus_one_ptid))
-    return 1;
+    return true;
 
   return this->beneath->supports_stopped_by_hw_breakpoint ();
 }
@@ -2746,7 +2746,7 @@ record_btrace_target::update_thread_list ()
 
 /* The thread_alive method of target record-btrace.  */
 
-int
+bool
 record_btrace_target::thread_alive (ptid_t ptid)
 {
   /* We don't add or remove threads during replay.  */
diff --git a/gdb/record-full.c b/gdb/record-full.c
index de96574baf..58f4be4fea 100644
--- a/gdb/record-full.c
+++ b/gdb/record-full.c
@@ -227,16 +227,16 @@ public:
   void close () override;
   void async (int) override;
   ptid_t wait (ptid_t, struct target_waitstatus *, int) override;
-  int stopped_by_watchpoint () override;
-  int stopped_data_address (CORE_ADDR *) override;
+  bool stopped_by_watchpoint () override;
+  bool stopped_data_address (CORE_ADDR *) override;
 
-  int stopped_by_sw_breakpoint () override;
-  int supports_stopped_by_sw_breakpoint () override;
+  bool stopped_by_sw_breakpoint () override;
+  bool supports_stopped_by_sw_breakpoint () override;
 
-  int stopped_by_hw_breakpoint () override;
-  int supports_stopped_by_hw_breakpoint () override;
+  bool stopped_by_hw_breakpoint () override;
+  bool supports_stopped_by_hw_breakpoint () override;
 
-  int can_execute_reverse () override;
+  bool can_execute_reverse () override;
 
   /* Add bookmark target methods.  */
   gdb_byte *get_bookmark (const char *, int) override;
@@ -247,8 +247,8 @@ public:
   void save_record (const char *filename) override;
   bool supports_delete_record () override;
   void delete_record () override;
-  int record_is_replaying (ptid_t ptid) override;
-  int record_will_replay (ptid_t ptid, int dir) override;
+  bool record_is_replaying (ptid_t ptid) override;
+  bool record_will_replay (ptid_t ptid, int dir) override;
   void record_stop_replaying () override;
   void goto_record_begin () override;
   void goto_record_end () override;
@@ -309,7 +309,7 @@ public:
 			 struct bp_target_info *,
 			 enum remove_bp_reason) override;
 
-  int has_execution (ptid_t) override;
+  bool has_execution (ptid_t) override;
 };
 
 static record_full_target record_full_ops;
@@ -1463,7 +1463,7 @@ record_full_base_target::wait (ptid_t ptid, struct target_waitstatus *status,
   return return_ptid;
 }
 
-int
+bool
 record_full_base_target::stopped_by_watchpoint ()
 {
   if (RECORD_FULL_IS_REPLAY)
@@ -1472,18 +1472,18 @@ record_full_base_target::stopped_by_watchpoint ()
     return beneath->stopped_by_watchpoint ();
 }
 
-int
+bool
 record_full_base_target::stopped_data_address (CORE_ADDR *addr_p)
 {
   if (RECORD_FULL_IS_REPLAY)
-    return 0;
+    return false;
   else
     return this->beneath->stopped_data_address (addr_p);
 }
 
 /* The stopped_by_sw_breakpoint method of target record-full.  */
 
-int
+bool
 record_full_base_target::stopped_by_sw_breakpoint ()
 {
   return record_full_stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT;
@@ -1492,15 +1492,15 @@ record_full_base_target::stopped_by_sw_breakpoint ()
 /* The supports_stopped_by_sw_breakpoint method of target
    record-full.  */
 
-int
+bool
 record_full_base_target::supports_stopped_by_sw_breakpoint ()
 {
-  return 1;
+  return true;
 }
 
 /* The stopped_by_hw_breakpoint method of target record-full.  */
 
-int
+bool
 record_full_base_target::stopped_by_hw_breakpoint ()
 {
   return record_full_stop_reason == TARGET_STOPPED_BY_HW_BREAKPOINT;
@@ -1509,10 +1509,10 @@ record_full_base_target::stopped_by_hw_breakpoint ()
 /* The supports_stopped_by_sw_breakpoint method of target
    record-full.  */
 
-int
+bool
 record_full_base_target::supports_stopped_by_hw_breakpoint ()
 {
-  return 1;
+  return true;
 }
 
 /* Record registers change (by user or by GDB) to list as an instruction.  */
@@ -1834,10 +1834,10 @@ record_full_target::remove_breakpoint (struct gdbarch *gdbarch,
 
 /* "can_execute_reverse" method for process record target.  */
 
-int
+bool
 record_full_base_target::can_execute_reverse ()
 {
-  return 1;
+  return true;
 }
 
 /* "get_bookmark" method for process record and prec over core.  */
@@ -1962,7 +1962,7 @@ record_full_base_target::delete_record ()
 
 /* The "record_is_replaying" target method.  */
 
-int
+bool
 record_full_base_target::record_is_replaying (ptid_t ptid)
 {
   return RECORD_FULL_IS_REPLAY;
@@ -1970,7 +1970,7 @@ record_full_base_target::record_is_replaying (ptid_t ptid)
 
 /* The "record_will_replay" target method.  */
 
-int
+bool
 record_full_base_target::record_will_replay (ptid_t ptid, int dir)
 {
   /* We can currently only record when executing forwards.  Should we be able
@@ -2240,10 +2240,10 @@ record_full_core_target::remove_breakpoint (struct gdbarch *gdbarch,
 
 /* "has_execution" method for prec over corefile.  */
 
-int
+bool
 record_full_core_target::has_execution (ptid_t the_ptid)
 {
-  return 1;
+  return true;
 }
 
 /* Record log save-file format
diff --git a/gdb/remote-sim.c b/gdb/remote-sim.c
index 3d484bcd85..91dbd7c7bb 100644
--- a/gdb/remote-sim.c
+++ b/gdb/remote-sim.c
@@ -123,20 +123,20 @@ struct gdbsim_target
 
   void interrupt () override;
 
-  int thread_alive (ptid_t ptid) override;
+  bool thread_alive (ptid_t ptid) override;
 
   const char *pid_to_str (ptid_t) override;
 
-  int has_all_memory ()  override;
-  int has_memory ()  override;
+  bool has_all_memory ()  override;
+  bool has_memory ()  override;
 
-  int has_stack ()  override
+  bool has_stack ()  override
   { return default_child_has_stack (); }
 
-  int has_registers ()  override
+  bool has_registers ()  override
   { return default_child_has_registers (); }
 
-  int has_execution (ptid_t ptid) override
+  bool has_execution (ptid_t ptid) override
   { return default_child_has_execution (ptid); }
 };
 
@@ -1288,20 +1288,20 @@ sim_command_completer (struct cmd_list_element *ignore,
 
 /* Check to see if a thread is still alive.  */
 
-int
+bool
 gdbsim_target::thread_alive (ptid_t ptid)
 {
   struct sim_inferior_data *sim_data
     = get_sim_inferior_data_by_ptid (ptid, SIM_INSTANCE_NOT_NEEDED);
 
   if (sim_data == NULL)
-    return 0;
+    return false;
 
   if (ptid_equal (ptid, sim_data->remote_sim_ptid))
     /* The simulators' task is always alive.  */
-    return 1;
+    return true;
 
-  return 0;
+  return false;
 }
 
 /* Convert a thread ID to a string.  Returns the string in a static
@@ -1315,28 +1315,28 @@ gdbsim_target::pid_to_str (ptid_t ptid)
 
 /* Simulator memory may be accessed after the program has been loaded.  */
 
-int
+bool
 gdbsim_target::has_all_memory ()
 {
   struct sim_inferior_data *sim_data
     = get_sim_inferior_data (current_inferior (), SIM_INSTANCE_NOT_NEEDED);
 
   if (!sim_data->program_loaded)
-    return 0;
+    return false;
 
-  return 1;
+  return true;
 }
 
-int
+bool
 gdbsim_target::has_memory ()
 {
   struct sim_inferior_data *sim_data
     = get_sim_inferior_data (current_inferior (), SIM_INSTANCE_NOT_NEEDED);
 
   if (!sim_data->program_loaded)
-    return 0;
+    return false;
 
-  return 1;
+  return true;
 }
 
 void
diff --git a/gdb/remote.c b/gdb/remote.c
index 0b22b11c09..4790bc7f5e 100644
--- a/gdb/remote.c
+++ b/gdb/remote.c
@@ -125,18 +125,18 @@ Specify the serial device it is connected to\n\
 			 enum remove_bp_reason) override;
 
 
-  int stopped_by_sw_breakpoint () override;
-  int supports_stopped_by_sw_breakpoint () override;
+  bool stopped_by_sw_breakpoint () override;
+  bool supports_stopped_by_sw_breakpoint () override;
 
-  int stopped_by_hw_breakpoint () override;
+  bool stopped_by_hw_breakpoint () override;
 
-  int supports_stopped_by_hw_breakpoint () override;
+  bool supports_stopped_by_hw_breakpoint () override;
 
-  int stopped_by_watchpoint () override;
+  bool stopped_by_watchpoint () override;
 
-  int stopped_data_address (CORE_ADDR *) override;
+  bool stopped_data_address (CORE_ADDR *) override;
 
-  int watchpoint_addr_within_range (CORE_ADDR, CORE_ADDR, int) override;
+  bool watchpoint_addr_within_range (CORE_ADDR, CORE_ADDR, int) override;
 
   int can_use_hw_breakpoint (enum bptype, int, int) override;
 
@@ -165,7 +165,7 @@ Specify the serial device it is connected to\n\
 
   void program_signals (int, unsigned char *) override;
 
-  int thread_alive (ptid_t ptid) override;
+  bool thread_alive (ptid_t ptid) override;
 
   const char *thread_name (struct thread_info *) override;
 
@@ -209,13 +209,13 @@ Specify the serial device it is connected to\n\
 				      CORE_ADDR load_module_addr,
 				      CORE_ADDR offset) override;
 
-  int has_all_memory ()  override { return default_child_has_all_memory (); }
-  int has_memory ()  override { return default_child_has_memory (); }
-  int has_stack ()  override { return default_child_has_stack (); }
-  int has_registers ()  override { return default_child_has_registers (); }
-  int has_execution (ptid_t ptid)  override { return default_child_has_execution (ptid); }
+  bool has_all_memory ()  override { return default_child_has_all_memory (); }
+  bool has_memory ()  override { return default_child_has_memory (); }
+  bool has_stack ()  override { return default_child_has_stack (); }
+  bool has_registers ()  override { return default_child_has_registers (); }
+  bool has_execution (ptid_t ptid)  override { return default_child_has_execution (ptid); }
 
-  int can_execute_reverse () override;
+  bool can_execute_reverse () override;
 
   std::vector<mem_region> memory_map () override;
 
@@ -229,9 +229,9 @@ Specify the serial device it is connected to\n\
 		     const gdb_byte *pattern, ULONGEST pattern_len,
 		     CORE_ADDR *found_addrp) override;
 
-  int can_async_p () override;
+  bool can_async_p () override;
 
-  int is_async_p () override;
+  bool is_async_p () override;
 
   void async (int) override;
 
@@ -243,13 +243,13 @@ Specify the serial device it is connected to\n\
 
   void terminal_ours () override;
 
-  int supports_non_stop () override;
+  bool supports_non_stop () override;
 
-  int supports_multi_process () override;
+  bool supports_multi_process () override;
 
-  int supports_disable_randomization () override;
+  bool supports_disable_randomization () override;
 
-  int filesystem_is_local () override;
+  bool filesystem_is_local () override;
 
 
   int fileio_open (struct inferior *inf, const char *filename,
@@ -275,19 +275,19 @@ Specify the serial device it is connected to\n\
 		     const char *filename,
 		     int *target_errno) override;
 
-  int supports_enable_disable_tracepoint () override;
+  bool supports_enable_disable_tracepoint () override;
 
-  int supports_string_tracing () override;
+  bool supports_string_tracing () override;
 
-  int supports_evaluation_of_breakpoint_conditions () override;
+  bool supports_evaluation_of_breakpoint_conditions () override;
 
-  int can_run_breakpoint_commands () override;
+  bool can_run_breakpoint_commands () override;
 
   void trace_init () override;
 
   void download_tracepoint (struct bp_location *location) override;
 
-  int can_download_tracepoint () override;
+  bool can_download_tracepoint () override;
 
   void download_trace_state_variable (const trace_state_variable &tsv) override;
 
@@ -309,7 +309,7 @@ Specify the serial device it is connected to\n\
   int trace_find (enum trace_find_type type, int num,
 		  CORE_ADDR addr1, CORE_ADDR addr2, int *tpp) override;
 
-  int get_trace_state_variable_value (int tsv, LONGEST *val) override;
+  bool get_trace_state_variable_value (int tsv, LONGEST *val) override;
 
   int save_trace_data (const char *filename) override;
 
@@ -327,8 +327,8 @@ Specify the serial device it is connected to\n\
 
   void set_trace_buffer_size (LONGEST val) override;
 
-  int set_trace_notes (const char *user, const char *notes,
-		       const char *stopnotes) override;
+  bool set_trace_notes (const char *user, const char *notes,
+			const char *stopnotes) override;
 
   int core_of_thread (ptid_t ptid) override;
 
@@ -336,7 +336,7 @@ Specify the serial device it is connected to\n\
 		     CORE_ADDR memaddr, ULONGEST size) override;
 
 
-  int get_tib_address (ptid_t ptid, CORE_ADDR *addr) override;
+  bool get_tib_address (ptid_t ptid, CORE_ADDR *addr) override;
 
   void set_permissions () override;
 
@@ -349,8 +349,8 @@ Specify the serial device it is connected to\n\
 
   traceframe_info_up traceframe_info () override;
 
-  int use_agent (int use) override;
-  int can_use_agent () override;
+  bool use_agent (bool use) override;
+  bool can_use_agent () override;
 
   struct btrace_target_info *enable_btrace (ptid_t ptid,
 					    const struct btrace_config *conf) override;
@@ -364,7 +364,7 @@ Specify the serial device it is connected to\n\
 				 enum btrace_read_type type) override;
 
   const struct btrace_config *btrace_conf (const struct btrace_target_info *) override;
-  int augmented_libraries_svr4_read () override;
+  bool augmented_libraries_svr4_read () override;
   int follow_fork (int, int) override;
   void follow_exec (struct inferior *, char *) override;
   int insert_fork_catchpoint (int) override;
@@ -404,7 +404,7 @@ public:
   void attach (const char *, int) override;
 
   void post_attach (int) override;
-  int supports_disable_randomization () override;
+  bool supports_disable_randomization () override;
 };
 
 /* Per-program-space data key.  */
@@ -2520,7 +2520,7 @@ remote_thread_always_alive (ptid_t ptid)
 /* Return nonzero if the thread PTID is still alive on the remote
    system.  */
 
-int
+bool
 remote_target::thread_alive (ptid_t ptid)
 {
   struct remote_state *rs = get_remote_state ();
@@ -9702,7 +9702,7 @@ remote_target::mourn_inferior ()
     }
 }
 
-int
+bool
 extended_remote_target::supports_disable_randomization ()
 {
   return packet_support (PACKET_QDisableRandomization) == PACKET_ENABLE;
@@ -10160,7 +10160,7 @@ remote_target::insert_watchpoint (CORE_ADDR addr, int len,
 		  _("remote_insert_watchpoint: reached end of function"));
 }
 
-int
+bool
 remote_target::watchpoint_addr_within_range (CORE_ADDR addr,
 					     CORE_ADDR start, int length)
 {
@@ -10253,7 +10253,7 @@ remote_target::can_use_hw_breakpoint (enum bptype type, int cnt, int ot)
 
 /* The to_stopped_by_sw_breakpoint method of target remote.  */
 
-int
+bool
 remote_target::stopped_by_sw_breakpoint ()
 {
   struct thread_info *thread = inferior_thread ();
@@ -10266,7 +10266,7 @@ remote_target::stopped_by_sw_breakpoint ()
 /* The to_supports_stopped_by_sw_breakpoint method of target
    remote.  */
 
-int
+bool
 remote_target::supports_stopped_by_sw_breakpoint ()
 {
   return (packet_support (PACKET_swbreak_feature) == PACKET_ENABLE);
@@ -10274,7 +10274,7 @@ remote_target::supports_stopped_by_sw_breakpoint ()
 
 /* The to_stopped_by_hw_breakpoint method of target remote.  */
 
-int
+bool
 remote_target::stopped_by_hw_breakpoint ()
 {
   struct thread_info *thread = inferior_thread ();
@@ -10287,13 +10287,13 @@ remote_target::stopped_by_hw_breakpoint ()
 /* The to_supports_stopped_by_hw_breakpoint method of target
    remote.  */
 
-int
+bool
 remote_target::supports_stopped_by_hw_breakpoint ()
 {
   return (packet_support (PACKET_hwbreak_feature) == PACKET_ENABLE);
 }
 
-int
+bool
 remote_target::stopped_by_watchpoint ()
 {
   struct thread_info *thread = inferior_thread ();
@@ -10303,7 +10303,7 @@ remote_target::stopped_by_watchpoint ()
 	      == TARGET_STOPPED_BY_WATCHPOINT));
 }
 
-int
+bool
 remote_target::stopped_data_address (CORE_ADDR *addr_p)
 {
   struct thread_info *thread = inferior_thread ();
@@ -10313,10 +10313,10 @@ remote_target::stopped_data_address (CORE_ADDR *addr_p)
 	  == TARGET_STOPPED_BY_WATCHPOINT))
     {
       *addr_p = get_remote_thread_info (thread)->watch_data_address;
-      return 1;
+      return true;
     }
 
-  return 0;
+  return false;
 }
 
 
@@ -11332,7 +11332,7 @@ remote_target::get_thread_local_address (ptid_t ptid, CORE_ADDR lm,
 /* Provide thread local base, i.e. Thread Information Block address.
    Returns 1 if ptid is found and thread_local_base is non zero.  */
 
-int
+bool
 remote_target::get_tib_address (ptid_t ptid, CORE_ADDR *addr)
 {
   if (packet_support (PACKET_qGetTIBAddr) != PACKET_DISABLE)
@@ -11358,7 +11358,7 @@ remote_target::get_tib_address (ptid_t ptid, CORE_ADDR *addr)
 	  unpack_varlen_hex (rs->buf, &result);
 	  if (addr)
 	    *addr = (CORE_ADDR) result;
-	  return 1;
+	  return true;
 	}
       else if (result == PACKET_UNKNOWN)
 	error (_("Remote target doesn't support qGetTIBAddr packet"));
@@ -11368,7 +11368,7 @@ remote_target::get_tib_address (ptid_t ptid, CORE_ADDR *addr)
   else
     error (_("qGetTIBAddr not supported or disabled on this target"));
   /* Not reached.  */
-  return 0;
+  return false;
 }
 
 /* Support for inferring a target description based on the current
@@ -12087,7 +12087,7 @@ remote_target::fileio_fstat (int fd, struct stat *st, int *remote_errno)
 
 /* Implementation of to_filesystem_is_local.  */
 
-int
+bool
 remote_target::filesystem_is_local ()
 {
   /* Valgrind GDB presents itself as a remote target but works
@@ -12129,11 +12129,11 @@ remote_target::filesystem_is_local ()
 	      warning_issued = 1;
 	    }
 
-	  return 1;
+	  return true;
 	}
     }
 
-  return 0;
+  return false;
 }
 
 static int
@@ -12418,30 +12418,30 @@ remote_command (const char *args, int from_tty)
   help_list (remote_cmdlist, "remote ", all_commands, gdb_stdout);
 }
 
-int
+bool
 remote_target::can_execute_reverse ()
 {
   if (packet_support (PACKET_bs) == PACKET_ENABLE
       || packet_support (PACKET_bc) == PACKET_ENABLE)
-    return 1;
+    return true;
   else
-    return 0;
+    return false;
 }
 
-int
+bool
 remote_target::supports_non_stop ()
 {
-  return 1;
+  return true;
 }
 
-int
+bool
 remote_target::supports_disable_randomization ()
 {
   /* Only supported in extended mode.  */
-  return 0;
+  return false;
 }
 
-int
+bool
 remote_target::supports_multi_process ()
 {
   struct remote_state *rs = get_remote_state ();
@@ -12455,7 +12455,7 @@ remote_supports_cond_tracepoints ()
   return packet_support (PACKET_ConditionalTracepoints) == PACKET_ENABLE;
 }
 
-int
+bool
 remote_target::supports_evaluation_of_breakpoint_conditions ()
 {
   return packet_support (PACKET_ConditionalBreakpoints) == PACKET_ENABLE;
@@ -12479,20 +12479,20 @@ remote_supports_install_in_trace ()
   return packet_support (PACKET_InstallInTrace) == PACKET_ENABLE;
 }
 
-int
+bool
 remote_target::supports_enable_disable_tracepoint ()
 {
   return (packet_support (PACKET_EnableDisableTracepoints_feature)
 	  == PACKET_ENABLE);
 }
 
-int
+bool
 remote_target::supports_string_tracing ()
 {
   return packet_support (PACKET_tracenz_feature) == PACKET_ENABLE;
 }
 
-int
+bool
 remote_target::can_run_breakpoint_commands ()
 {
   return packet_support (PACKET_BreakpointCommands) == PACKET_ENABLE;
@@ -12713,7 +12713,7 @@ remote_target::download_tracepoint (struct bp_location *loc)
     }
 }
 
-int
+bool
 remote_target::can_download_tracepoint ()
 {
   struct remote_state *rs = get_remote_state ();
@@ -12724,20 +12724,20 @@ remote_target::can_download_tracepoint ()
      symbols, and fetched and merged the target's tracepoint list with
      ours.  */
   if (rs->starting_up)
-    return 0;
+    return false;
 
   ts = current_trace_status ();
   status = get_trace_status (ts);
 
   if (status == -1 || !ts->running_known || !ts->running)
-    return 0;
+    return false;
 
   /* If we are in a tracing experiment, but remote stub doesn't support
      installing tracepoint in trace, we have to return.  */
   if (!remote_supports_install_in_trace ())
-    return 0;
+    return false;
 
-  return 1;
+  return true;
 }
 
 
@@ -13055,7 +13055,7 @@ remote_target::trace_find (enum trace_find_type type, int num,
   return target_frameno;
 }
 
-int
+bool
 remote_target::get_trace_state_variable_value (int tsvnum, LONGEST *val)
 {
   struct remote_state *rs = get_remote_state ();
@@ -13073,10 +13073,10 @@ remote_target::get_trace_state_variable_value (int tsvnum, LONGEST *val)
 	{
 	  unpack_varlen_hex (reply + 1, &uval);
 	  *val = (LONGEST) uval;
-	  return 1;
+	  return true;
 	}
     }
-  return 0;
+  return false;
 }
 
 int
@@ -13268,7 +13268,7 @@ remote_target::set_trace_buffer_size (LONGEST val)
     }
 }
 
-int
+bool
 remote_target::set_trace_notes (const char *user, const char *notes,
 				const char *stop_notes)
 {
@@ -13306,16 +13306,16 @@ remote_target::set_trace_notes (const char *user, const char *notes,
   putpkt (rs->buf);
   reply = remote_get_noisy_reply ();
   if (*reply == '\0')
-    return 0;
+    return false;
 
   if (strcmp (reply, "OK") != 0)
     error (_("Bogus reply from target: %s"), reply);
 
-  return 1;
+  return true;
 }
 
-int
-remote_target::use_agent (int use)
+bool
+remote_target::use_agent (bool use)
 {
   if (packet_support (PACKET_QAgent) != PACKET_DISABLE)
     {
@@ -13329,14 +13329,14 @@ remote_target::use_agent (int use)
       if (strcmp (rs->buf, "OK") == 0)
 	{
 	  ::use_agent = use;
-	  return 1;
+	  return true;
 	}
     }
 
-  return 0;
+  return false;
 }
 
-int
+bool
 remote_target::can_use_agent ()
 {
   return (packet_support (PACKET_QAgent) != PACKET_DISABLE);
@@ -13637,7 +13637,7 @@ remote_target::btrace_conf (const struct btrace_target_info *tinfo)
   return &tinfo->conf;
 }
 
-int
+bool
 remote_target::augmented_libraries_svr4_read ()
 {
   return (packet_support (PACKET_augmented_libraries_svr4_read_feature)
@@ -13747,7 +13747,7 @@ remote_target::thread_handle_to_thread_info (const gdb_byte *thread_handle,
   return NULL;
 }
 
-int
+bool
 remote_target::can_async_p ()
 {
   struct remote_state *rs = get_remote_state ();
@@ -13755,20 +13755,20 @@ remote_target::can_async_p ()
   /* We don't go async if the user has explicitly prevented it with the
      "maint set target-async" command.  */
   if (!target_async_permitted)
-    return 0;
+    return false;
 
   /* We're async whenever the serial device is.  */
   return serial_can_async_p (rs->remote_desc);
 }
 
-int
+bool
 remote_target::is_async_p ()
 {
   struct remote_state *rs = get_remote_state ();
 
   if (!target_async_permitted)
     /* We only enable async when the user specifically asks for it.  */
-    return 0;
+    return false;
 
   /* We're async whenever the serial device is.  */
   return serial_is_async_p (rs->remote_desc);
diff --git a/gdb/s390-linux-nat.c b/gdb/s390-linux-nat.c
index d3d98014ac..2d82f53c04 100644
--- a/gdb/s390-linux-nat.c
+++ b/gdb/s390-linux-nat.c
@@ -122,9 +122,9 @@ public:
   int remove_hw_breakpoint (struct gdbarch *, struct bp_target_info *)
     override;
   int region_ok_for_hw_watchpoint (CORE_ADDR, int) override;
-  int have_continuable_watchpoint () { return 1; }
-  int stopped_by_watchpoint () override;
-  int watchpoint_addr_within_range (CORE_ADDR, CORE_ADDR, int) override;
+  bool have_continuable_watchpoint () { return 1; }
+  bool stopped_by_watchpoint () override;
+  bool watchpoint_addr_within_range (CORE_ADDR, CORE_ADDR, int) override;
   int insert_watchpoint (CORE_ADDR, int, enum target_hw_bp_type,
 			 struct expression *) override;
   int remove_watchpoint (CORE_ADDR, int, enum target_hw_bp_type,
@@ -657,21 +657,20 @@ s390_show_debug_regs (int tid, const char *where)
 		per_info.lowcore.words.access_id);
 }
 
-int
+bool
 s390_linux_nat_target::stopped_by_watchpoint ()
 {
   struct s390_debug_reg_state *state
     = s390_get_debug_reg_state (ptid_get_pid (inferior_ptid));
   per_lowcore_bits per_lowcore;
   ptrace_area parea;
-  int result;
 
   if (show_debug_regs)
     s390_show_debug_regs (s390_inferior_tid (), "stop");
 
   /* Speed up common case.  */
   if (VEC_empty (s390_watch_area, state->watch_areas))
-    return 0;
+    return false;
 
   parea.len = sizeof (per_lowcore);
   parea.process_addr = (addr_t) & per_lowcore;
@@ -679,8 +678,8 @@ s390_linux_nat_target::stopped_by_watchpoint ()
   if (ptrace (PTRACE_PEEKUSR_AREA, s390_inferior_tid (), &parea, 0) < 0)
     perror_with_name (_("Couldn't retrieve watchpoint status"));
 
-  result = (per_lowcore.perc_storage_alteration == 1
-	    && per_lowcore.perc_store_real_address == 0);
+  bool result = (per_lowcore.perc_storage_alteration == 1
+		 && per_lowcore.perc_store_real_address == 0);
 
   if (result)
     {
diff --git a/gdb/sol-thread.c b/gdb/sol-thread.c
index 0572da30c0..8f2ac3a6a3 100644
--- a/gdb/sol-thread.c
+++ b/gdb/sol-thread.c
@@ -99,7 +99,7 @@ public:
 					ULONGEST offset, ULONGEST len,
 					ULONGEST *xfered_len) override;
 
-  int thread_alive (ptid_t ptid) override;
+  bool thread_alive (ptid_t ptid) override;
   void update_thread_list () override;
 };
 
@@ -700,7 +700,7 @@ sol_thread_target::mourn_inferior ()
 
 /* Return true if PTID is still active in the inferior.  */
 
-int
+bool
 sol_thread_target::thread_alive (ptid_t ptid)
 {
   if (ptid_tid_p (ptid))
@@ -712,10 +712,10 @@ sol_thread_target::thread_alive (ptid_t ptid)
 
       pid = ptid_get_tid (ptid);
       if ((val = p_td_ta_map_id2thr (main_ta, pid, &th)) != TD_OK)
-	return 0;		/* Thread not found.  */
+	return false;		/* Thread not found.  */
       if ((val = p_td_thr_validate (&th)) != TD_OK)
-	return 0;		/* Thread not valid.  */
-      return 1;			/* Known thread.  */
+	return false;		/* Thread not valid.  */
+      return true;		/* Known thread.  */
     }
   else
     {
diff --git a/gdb/spu-multiarch.c b/gdb/spu-multiarch.c
index 4e3397fdfe..1886807d37 100644
--- a/gdb/spu-multiarch.c
+++ b/gdb/spu-multiarch.c
@@ -52,7 +52,7 @@ struct spu_multiarch_target final : public target_ops
 
   void mourn_inferior () override;
 
-    void fetch_registers (struct regcache *, int) override;
+  void fetch_registers (struct regcache *, int) override;
   void store_registers (struct regcache *, int) override;
 
   enum target_xfer_status xfer_partial (enum target_object object,
@@ -162,6 +162,7 @@ spu_multiarch_target::thread_architecture (ptid_t ptid)
 }
 
 /* Override the to_region_ok_for_hw_watchpoint routine.  */
+
 int
 spu_multiarch_target::region_ok_for_hw_watchpoint (CORE_ADDR addr, int len)
 {
diff --git a/gdb/target-delegates.c b/gdb/target-delegates.c
index 3aea00ea9d..c06b700d6f 100644
--- a/gdb/target-delegates.c
+++ b/gdb/target-delegates.c
@@ -24,10 +24,10 @@ struct dummy_target : public target_ops
   void files_info () override;
   int insert_breakpoint (struct gdbarch *arg0, struct bp_target_info *arg1) override;
   int remove_breakpoint (struct gdbarch *arg0, struct bp_target_info *arg1, enum remove_bp_reason arg2) override;
-  int stopped_by_sw_breakpoint () override;
-  int supports_stopped_by_sw_breakpoint () override;
-  int stopped_by_hw_breakpoint () override;
-  int supports_stopped_by_hw_breakpoint () override;
+  bool stopped_by_sw_breakpoint () override;
+  bool supports_stopped_by_sw_breakpoint () override;
+  bool stopped_by_hw_breakpoint () override;
+  bool supports_stopped_by_hw_breakpoint () override;
   int can_use_hw_breakpoint (enum bptype arg0, int arg1, int arg2) override;
   int ranged_break_num_registers () override;
   int insert_hw_breakpoint (struct gdbarch *arg0, struct bp_target_info *arg1) override;
@@ -36,13 +36,13 @@ struct dummy_target : public target_ops
   int insert_watchpoint (CORE_ADDR arg0, int arg1, enum target_hw_bp_type arg2, struct expression *arg3) override;
   int insert_mask_watchpoint (CORE_ADDR arg0, CORE_ADDR arg1, enum target_hw_bp_type arg2) override;
   int remove_mask_watchpoint (CORE_ADDR arg0, CORE_ADDR arg1, enum target_hw_bp_type arg2) override;
-  int stopped_by_watchpoint () override;
+  bool stopped_by_watchpoint () override;
   int have_steppable_watchpoint () override;
   bool have_continuable_watchpoint () override;
-  int stopped_data_address (CORE_ADDR *arg0) override;
-  int watchpoint_addr_within_range (CORE_ADDR arg0, CORE_ADDR arg1, int arg2) override;
+  bool stopped_data_address (CORE_ADDR *arg0) override;
+  bool watchpoint_addr_within_range (CORE_ADDR arg0, CORE_ADDR arg1, int arg2) override;
   int region_ok_for_hw_watchpoint (CORE_ADDR arg0, int arg1) override;
-  int can_accel_watchpoint_condition (CORE_ADDR arg0, int arg1, int arg2, struct expression *arg3) override;
+  bool can_accel_watchpoint_condition (CORE_ADDR arg0, int arg1, int arg2, struct expression *arg3) override;
   int masked_watch_num_registers (CORE_ADDR arg0, CORE_ADDR arg1) override;
   int can_do_single_step () override;
   bool supports_terminal_ours () override;
@@ -67,7 +67,7 @@ struct dummy_target : public target_ops
   void mourn_inferior () override;
   void pass_signals (int arg0, unsigned char * arg1) override;
   void program_signals (int arg0, unsigned char * arg1) override;
-  int thread_alive (ptid_t arg0) override;
+  bool thread_alive (ptid_t arg0) override;
   void update_thread_list () override;
   const char *pid_to_str (ptid_t arg0) override;
   const char *extra_thread_info (thread_info *arg0) override;
@@ -82,12 +82,12 @@ struct dummy_target : public target_ops
   struct target_section_table *get_section_table () override;
   thread_control_capabilities get_thread_control_capabilities () override;
   bool attach_no_wait () override;
-  int can_async_p () override;
-  int is_async_p () override;
+  bool can_async_p () override;
+  bool is_async_p () override;
   void async (int arg0) override;
   void thread_events (int arg0) override;
-  int supports_non_stop () override;
-  int always_non_stop_p () override;
+  bool supports_non_stop () override;
+  bool always_non_stop_p () override;
   int find_memory_regions (find_memory_region_ftype arg0, void *arg1) override;
   char *make_corefile_notes (bfd *arg0, int *arg1) override;
   gdb_byte *get_bookmark (const char *arg0, int arg1) override;
@@ -102,20 +102,20 @@ struct dummy_target : public target_ops
   ptid_t get_ada_task_ptid (long arg0, long arg1) override;
   int auxv_parse (gdb_byte **arg0, gdb_byte *arg1, CORE_ADDR *arg2, CORE_ADDR *arg3) override;
   int search_memory (CORE_ADDR arg0, ULONGEST arg1, const gdb_byte *arg2, ULONGEST arg3, CORE_ADDR *arg4) override;
-  int can_execute_reverse () override;
+  bool can_execute_reverse () override;
   enum exec_direction_kind execution_direction () override;
-  int supports_multi_process () override;
-  int supports_enable_disable_tracepoint () override;
-  int supports_disable_randomization () override;
-  int supports_string_tracing () override;
-  int supports_evaluation_of_breakpoint_conditions () override;
-  int can_run_breakpoint_commands () override;
+  bool supports_multi_process () override;
+  bool supports_enable_disable_tracepoint () override;
+  bool supports_disable_randomization () override;
+  bool supports_string_tracing () override;
+  bool supports_evaluation_of_breakpoint_conditions () override;
+  bool can_run_breakpoint_commands () override;
   struct gdbarch *thread_architecture (ptid_t arg0) override;
   struct address_space *thread_address_space (ptid_t arg0) override;
-  int filesystem_is_local () override;
+  bool filesystem_is_local () override;
   void trace_init () override;
   void download_tracepoint (struct bp_location *arg0) override;
-  int can_download_tracepoint () override;
+  bool can_download_tracepoint () override;
   void download_trace_state_variable (const trace_state_variable &arg0) override;
   void enable_tracepoint (struct bp_location *arg0) override;
   void disable_tracepoint (struct bp_location *arg0) override;
@@ -125,7 +125,7 @@ struct dummy_target : public target_ops
   void get_tracepoint_status (struct breakpoint *arg0, struct uploaded_tp *arg1) override;
   void trace_stop () override;
   int trace_find (enum trace_find_type arg0, int arg1, CORE_ADDR arg2, CORE_ADDR arg3, int *arg4) override;
-  int get_trace_state_variable_value (int arg0, LONGEST *arg1) override;
+  bool get_trace_state_variable_value (int arg0, LONGEST *arg1) override;
   int save_trace_data (const char *arg0) override;
   int upload_tracepoints (struct uploaded_tp **arg0) override;
   int upload_trace_state_variables (struct uploaded_tsv **arg0) override;
@@ -134,16 +134,16 @@ struct dummy_target : public target_ops
   void set_disconnected_tracing (int arg0) override;
   void set_circular_trace_buffer (int arg0) override;
   void set_trace_buffer_size (LONGEST arg0) override;
-  int set_trace_notes (const char *arg0, const char *arg1, const char *arg2) override;
+  bool set_trace_notes (const char *arg0, const char *arg1, const char *arg2) override;
   int core_of_thread (ptid_t arg0) override;
   int verify_memory (const gdb_byte *arg0, CORE_ADDR arg1, ULONGEST arg2) override;
-  int get_tib_address (ptid_t arg0, CORE_ADDR *arg1) override;
+  bool get_tib_address (ptid_t arg0, CORE_ADDR *arg1) override;
   void set_permissions () override;
   bool static_tracepoint_marker_at (CORE_ADDR arg0, static_tracepoint_marker *arg1) override;
   std::vector<static_tracepoint_marker> static_tracepoint_markers_by_strid (const char *arg0) override;
   traceframe_info_up traceframe_info () override;
-  int use_agent (int arg0) override;
-  int can_use_agent () override;
+  bool use_agent (bool arg0) override;
+  bool can_use_agent () override;
   struct btrace_target_info *enable_btrace (ptid_t arg0, const struct btrace_config *arg1) override;
   void disable_btrace (struct btrace_target_info *arg0) override;
   void teardown_btrace (struct btrace_target_info *arg0) override;
@@ -155,8 +155,8 @@ struct dummy_target : public target_ops
   void save_record (const char *arg0) override;
   bool supports_delete_record () override;
   void delete_record () override;
-  int record_is_replaying (ptid_t arg0) override;
-  int record_will_replay (ptid_t arg0, int arg1) override;
+  bool record_is_replaying (ptid_t arg0) override;
+  bool record_will_replay (ptid_t arg0, int arg1) override;
   void record_stop_replaying () override;
   void goto_record_begin () override;
   void goto_record_end () override;
@@ -167,7 +167,7 @@ struct dummy_target : public target_ops
   void call_history (int arg0, record_print_flags arg1) override;
   void call_history_from (ULONGEST arg0, int arg1, record_print_flags arg2) override;
   void call_history_range (ULONGEST arg0, ULONGEST arg1, record_print_flags arg2) override;
-  int augmented_libraries_svr4_read () override;
+  bool augmented_libraries_svr4_read () override;
   const struct frame_unwind *get_unwinder () override;
   const struct frame_unwind *get_tailcall_unwinder () override;
   void prepare_to_generate_core () override;
@@ -194,10 +194,10 @@ struct debug_target : public target_ops
   void files_info () override;
   int insert_breakpoint (struct gdbarch *arg0, struct bp_target_info *arg1) override;
   int remove_breakpoint (struct gdbarch *arg0, struct bp_target_info *arg1, enum remove_bp_reason arg2) override;
-  int stopped_by_sw_breakpoint () override;
-  int supports_stopped_by_sw_breakpoint () override;
-  int stopped_by_hw_breakpoint () override;
-  int supports_stopped_by_hw_breakpoint () override;
+  bool stopped_by_sw_breakpoint () override;
+  bool supports_stopped_by_sw_breakpoint () override;
+  bool stopped_by_hw_breakpoint () override;
+  bool supports_stopped_by_hw_breakpoint () override;
   int can_use_hw_breakpoint (enum bptype arg0, int arg1, int arg2) override;
   int ranged_break_num_registers () override;
   int insert_hw_breakpoint (struct gdbarch *arg0, struct bp_target_info *arg1) override;
@@ -206,13 +206,13 @@ struct debug_target : public target_ops
   int insert_watchpoint (CORE_ADDR arg0, int arg1, enum target_hw_bp_type arg2, struct expression *arg3) override;
   int insert_mask_watchpoint (CORE_ADDR arg0, CORE_ADDR arg1, enum target_hw_bp_type arg2) override;
   int remove_mask_watchpoint (CORE_ADDR arg0, CORE_ADDR arg1, enum target_hw_bp_type arg2) override;
-  int stopped_by_watchpoint () override;
+  bool stopped_by_watchpoint () override;
   int have_steppable_watchpoint () override;
   bool have_continuable_watchpoint () override;
-  int stopped_data_address (CORE_ADDR *arg0) override;
-  int watchpoint_addr_within_range (CORE_ADDR arg0, CORE_ADDR arg1, int arg2) override;
+  bool stopped_data_address (CORE_ADDR *arg0) override;
+  bool watchpoint_addr_within_range (CORE_ADDR arg0, CORE_ADDR arg1, int arg2) override;
   int region_ok_for_hw_watchpoint (CORE_ADDR arg0, int arg1) override;
-  int can_accel_watchpoint_condition (CORE_ADDR arg0, int arg1, int arg2, struct expression *arg3) override;
+  bool can_accel_watchpoint_condition (CORE_ADDR arg0, int arg1, int arg2, struct expression *arg3) override;
   int masked_watch_num_registers (CORE_ADDR arg0, CORE_ADDR arg1) override;
   int can_do_single_step () override;
   bool supports_terminal_ours () override;
@@ -237,7 +237,7 @@ struct debug_target : public target_ops
   void mourn_inferior () override;
   void pass_signals (int arg0, unsigned char * arg1) override;
   void program_signals (int arg0, unsigned char * arg1) override;
-  int thread_alive (ptid_t arg0) override;
+  bool thread_alive (ptid_t arg0) override;
   void update_thread_list () override;
   const char *pid_to_str (ptid_t arg0) override;
   const char *extra_thread_info (thread_info *arg0) override;
@@ -252,12 +252,12 @@ struct debug_target : public target_ops
   struct target_section_table *get_section_table () override;
   thread_control_capabilities get_thread_control_capabilities () override;
   bool attach_no_wait () override;
-  int can_async_p () override;
-  int is_async_p () override;
+  bool can_async_p () override;
+  bool is_async_p () override;
   void async (int arg0) override;
   void thread_events (int arg0) override;
-  int supports_non_stop () override;
-  int always_non_stop_p () override;
+  bool supports_non_stop () override;
+  bool always_non_stop_p () override;
   int find_memory_regions (find_memory_region_ftype arg0, void *arg1) override;
   char *make_corefile_notes (bfd *arg0, int *arg1) override;
   gdb_byte *get_bookmark (const char *arg0, int arg1) override;
@@ -272,20 +272,20 @@ struct debug_target : public target_ops
   ptid_t get_ada_task_ptid (long arg0, long arg1) override;
   int auxv_parse (gdb_byte **arg0, gdb_byte *arg1, CORE_ADDR *arg2, CORE_ADDR *arg3) override;
   int search_memory (CORE_ADDR arg0, ULONGEST arg1, const gdb_byte *arg2, ULONGEST arg3, CORE_ADDR *arg4) override;
-  int can_execute_reverse () override;
+  bool can_execute_reverse () override;
   enum exec_direction_kind execution_direction () override;
-  int supports_multi_process () override;
-  int supports_enable_disable_tracepoint () override;
-  int supports_disable_randomization () override;
-  int supports_string_tracing () override;
-  int supports_evaluation_of_breakpoint_conditions () override;
-  int can_run_breakpoint_commands () override;
+  bool supports_multi_process () override;
+  bool supports_enable_disable_tracepoint () override;
+  bool supports_disable_randomization () override;
+  bool supports_string_tracing () override;
+  bool supports_evaluation_of_breakpoint_conditions () override;
+  bool can_run_breakpoint_commands () override;
   struct gdbarch *thread_architecture (ptid_t arg0) override;
   struct address_space *thread_address_space (ptid_t arg0) override;
-  int filesystem_is_local () override;
+  bool filesystem_is_local () override;
   void trace_init () override;
   void download_tracepoint (struct bp_location *arg0) override;
-  int can_download_tracepoint () override;
+  bool can_download_tracepoint () override;
   void download_trace_state_variable (const trace_state_variable &arg0) override;
   void enable_tracepoint (struct bp_location *arg0) override;
   void disable_tracepoint (struct bp_location *arg0) override;
@@ -295,7 +295,7 @@ struct debug_target : public target_ops
   void get_tracepoint_status (struct breakpoint *arg0, struct uploaded_tp *arg1) override;
   void trace_stop () override;
   int trace_find (enum trace_find_type arg0, int arg1, CORE_ADDR arg2, CORE_ADDR arg3, int *arg4) override;
-  int get_trace_state_variable_value (int arg0, LONGEST *arg1) override;
+  bool get_trace_state_variable_value (int arg0, LONGEST *arg1) override;
   int save_trace_data (const char *arg0) override;
   int upload_tracepoints (struct uploaded_tp **arg0) override;
   int upload_trace_state_variables (struct uploaded_tsv **arg0) override;
@@ -304,16 +304,16 @@ struct debug_target : public target_ops
   void set_disconnected_tracing (int arg0) override;
   void set_circular_trace_buffer (int arg0) override;
   void set_trace_buffer_size (LONGEST arg0) override;
-  int set_trace_notes (const char *arg0, const char *arg1, const char *arg2) override;
+  bool set_trace_notes (const char *arg0, const char *arg1, const char *arg2) override;
   int core_of_thread (ptid_t arg0) override;
   int verify_memory (const gdb_byte *arg0, CORE_ADDR arg1, ULONGEST arg2) override;
-  int get_tib_address (ptid_t arg0, CORE_ADDR *arg1) override;
+  bool get_tib_address (ptid_t arg0, CORE_ADDR *arg1) override;
   void set_permissions () override;
   bool static_tracepoint_marker_at (CORE_ADDR arg0, static_tracepoint_marker *arg1) override;
   std::vector<static_tracepoint_marker> static_tracepoint_markers_by_strid (const char *arg0) override;
   traceframe_info_up traceframe_info () override;
-  int use_agent (int arg0) override;
-  int can_use_agent () override;
+  bool use_agent (bool arg0) override;
+  bool can_use_agent () override;
   struct btrace_target_info *enable_btrace (ptid_t arg0, const struct btrace_config *arg1) override;
   void disable_btrace (struct btrace_target_info *arg0) override;
   void teardown_btrace (struct btrace_target_info *arg0) override;
@@ -325,8 +325,8 @@ struct debug_target : public target_ops
   void save_record (const char *arg0) override;
   bool supports_delete_record () override;
   void delete_record () override;
-  int record_is_replaying (ptid_t arg0) override;
-  int record_will_replay (ptid_t arg0, int arg1) override;
+  bool record_is_replaying (ptid_t arg0) override;
+  bool record_will_replay (ptid_t arg0, int arg1) override;
   void record_stop_replaying () override;
   void goto_record_begin () override;
   void goto_record_end () override;
@@ -337,7 +337,7 @@ struct debug_target : public target_ops
   void call_history (int arg0, record_print_flags arg1) override;
   void call_history_from (ULONGEST arg0, int arg1, record_print_flags arg2) override;
   void call_history_range (ULONGEST arg0, ULONGEST arg1, record_print_flags arg2) override;
-  int augmented_libraries_svr4_read () override;
+  bool augmented_libraries_svr4_read () override;
   const struct frame_unwind *get_unwinder () override;
   const struct frame_unwind *get_tailcall_unwinder () override;
   void prepare_to_generate_core () override;
@@ -635,102 +635,102 @@ debug_target::remove_breakpoint (struct gdbarch *arg0, struct bp_target_info *ar
   return result;
 }
 
-int
+bool
 target_ops::stopped_by_sw_breakpoint ()
 {
   return this->beneath->stopped_by_sw_breakpoint ();
 }
 
-int
+bool
 dummy_target::stopped_by_sw_breakpoint ()
 {
-  return 0;
+  return false;
 }
 
-int
+bool
 debug_target::stopped_by_sw_breakpoint ()
 {
-  int result;
+  bool result;
   fprintf_unfiltered (gdb_stdlog, "-> %s->stopped_by_sw_breakpoint (...)\n", this->beneath->shortname ());
   result = this->beneath->stopped_by_sw_breakpoint ();
   fprintf_unfiltered (gdb_stdlog, "<- %s->stopped_by_sw_breakpoint (", this->beneath->shortname ());
   fputs_unfiltered (") = ", gdb_stdlog);
-  target_debug_print_int (result);
+  target_debug_print_bool (result);
   fputs_unfiltered ("\n", gdb_stdlog);
   return result;
 }
 
-int
+bool
 target_ops::supports_stopped_by_sw_breakpoint ()
 {
   return this->beneath->supports_stopped_by_sw_breakpoint ();
 }
 
-int
+bool
 dummy_target::supports_stopped_by_sw_breakpoint ()
 {
-  return 0;
+  return false;
 }
 
-int
+bool
 debug_target::supports_stopped_by_sw_breakpoint ()
 {
-  int result;
+  bool result;
   fprintf_unfiltered (gdb_stdlog, "-> %s->supports_stopped_by_sw_breakpoint (...)\n", this->beneath->shortname ());
   result = this->beneath->supports_stopped_by_sw_breakpoint ();
   fprintf_unfiltered (gdb_stdlog, "<- %s->supports_stopped_by_sw_breakpoint (", this->beneath->shortname ());
   fputs_unfiltered (") = ", gdb_stdlog);
-  target_debug_print_int (result);
+  target_debug_print_bool (result);
   fputs_unfiltered ("\n", gdb_stdlog);
   return result;
 }
 
-int
+bool
 target_ops::stopped_by_hw_breakpoint ()
 {
   return this->beneath->stopped_by_hw_breakpoint ();
 }
 
-int
+bool
 dummy_target::stopped_by_hw_breakpoint ()
 {
-  return 0;
+  return false;
 }
 
-int
+bool
 debug_target::stopped_by_hw_breakpoint ()
 {
-  int result;
+  bool result;
   fprintf_unfiltered (gdb_stdlog, "-> %s->stopped_by_hw_breakpoint (...)\n", this->beneath->shortname ());
   result = this->beneath->stopped_by_hw_breakpoint ();
   fprintf_unfiltered (gdb_stdlog, "<- %s->stopped_by_hw_breakpoint (", this->beneath->shortname ());
   fputs_unfiltered (") = ", gdb_stdlog);
-  target_debug_print_int (result);
+  target_debug_print_bool (result);
   fputs_unfiltered ("\n", gdb_stdlog);
   return result;
 }
 
-int
+bool
 target_ops::supports_stopped_by_hw_breakpoint ()
 {
   return this->beneath->supports_stopped_by_hw_breakpoint ();
 }
 
-int
+bool
 dummy_target::supports_stopped_by_hw_breakpoint ()
 {
-  return 0;
+  return false;
 }
 
-int
+bool
 debug_target::supports_stopped_by_hw_breakpoint ()
 {
-  int result;
+  bool result;
   fprintf_unfiltered (gdb_stdlog, "-> %s->supports_stopped_by_hw_breakpoint (...)\n", this->beneath->shortname ());
   result = this->beneath->supports_stopped_by_hw_breakpoint ();
   fprintf_unfiltered (gdb_stdlog, "<- %s->supports_stopped_by_hw_breakpoint (", this->beneath->shortname ());
   fputs_unfiltered (") = ", gdb_stdlog);
-  target_debug_print_int (result);
+  target_debug_print_bool (result);
   fputs_unfiltered ("\n", gdb_stdlog);
   return result;
 }
@@ -970,27 +970,27 @@ debug_target::remove_mask_watchpoint (CORE_ADDR arg0, CORE_ADDR arg1, enum targe
   return result;
 }
 
-int
+bool
 target_ops::stopped_by_watchpoint ()
 {
   return this->beneath->stopped_by_watchpoint ();
 }
 
-int
+bool
 dummy_target::stopped_by_watchpoint ()
 {
-  return 0;
+  return false;
 }
 
-int
+bool
 debug_target::stopped_by_watchpoint ()
 {
-  int result;
+  bool result;
   fprintf_unfiltered (gdb_stdlog, "-> %s->stopped_by_watchpoint (...)\n", this->beneath->shortname ());
   result = this->beneath->stopped_by_watchpoint ();
   fprintf_unfiltered (gdb_stdlog, "<- %s->stopped_by_watchpoint (", this->beneath->shortname ());
   fputs_unfiltered (") = ", gdb_stdlog);
-  target_debug_print_int (result);
+  target_debug_print_bool (result);
   fputs_unfiltered ("\n", gdb_stdlog);
   return result;
 }
@@ -1004,7 +1004,7 @@ target_ops::have_steppable_watchpoint ()
 int
 dummy_target::have_steppable_watchpoint ()
 {
-  return 0;
+  return false;
 }
 
 int
@@ -1029,7 +1029,7 @@ target_ops::have_continuable_watchpoint ()
 bool
 dummy_target::have_continuable_watchpoint ()
 {
-  return 0;
+  return false;
 }
 
 bool
@@ -1045,48 +1045,48 @@ debug_target::have_continuable_watchpoint ()
   return result;
 }
 
-int
+bool
 target_ops::stopped_data_address (CORE_ADDR *arg0)
 {
   return this->beneath->stopped_data_address (arg0);
 }
 
-int
+bool
 dummy_target::stopped_data_address (CORE_ADDR *arg0)
 {
-  return 0;
+  return false;
 }
 
-int
+bool
 debug_target::stopped_data_address (CORE_ADDR *arg0)
 {
-  int result;
+  bool result;
   fprintf_unfiltered (gdb_stdlog, "-> %s->stopped_data_address (...)\n", this->beneath->shortname ());
   result = this->beneath->stopped_data_address (arg0);
   fprintf_unfiltered (gdb_stdlog, "<- %s->stopped_data_address (", this->beneath->shortname ());
   target_debug_print_CORE_ADDR_p (arg0);
   fputs_unfiltered (") = ", gdb_stdlog);
-  target_debug_print_int (result);
+  target_debug_print_bool (result);
   fputs_unfiltered ("\n", gdb_stdlog);
   return result;
 }
 
-int
+bool
 target_ops::watchpoint_addr_within_range (CORE_ADDR arg0, CORE_ADDR arg1, int arg2)
 {
   return this->beneath->watchpoint_addr_within_range (arg0, arg1, arg2);
 }
 
-int
+bool
 dummy_target::watchpoint_addr_within_range (CORE_ADDR arg0, CORE_ADDR arg1, int arg2)
 {
   return default_watchpoint_addr_within_range (this, arg0, arg1, arg2);
 }
 
-int
+bool
 debug_target::watchpoint_addr_within_range (CORE_ADDR arg0, CORE_ADDR arg1, int arg2)
 {
-  int result;
+  bool result;
   fprintf_unfiltered (gdb_stdlog, "-> %s->watchpoint_addr_within_range (...)\n", this->beneath->shortname ());
   result = this->beneath->watchpoint_addr_within_range (arg0, arg1, arg2);
   fprintf_unfiltered (gdb_stdlog, "<- %s->watchpoint_addr_within_range (", this->beneath->shortname ());
@@ -1096,7 +1096,7 @@ debug_target::watchpoint_addr_within_range (CORE_ADDR arg0, CORE_ADDR arg1, int
   fputs_unfiltered (", ", gdb_stdlog);
   target_debug_print_int (arg2);
   fputs_unfiltered (") = ", gdb_stdlog);
-  target_debug_print_int (result);
+  target_debug_print_bool (result);
   fputs_unfiltered ("\n", gdb_stdlog);
   return result;
 }
@@ -1129,22 +1129,22 @@ debug_target::region_ok_for_hw_watchpoint (CORE_ADDR arg0, int arg1)
   return result;
 }
 
-int
+bool
 target_ops::can_accel_watchpoint_condition (CORE_ADDR arg0, int arg1, int arg2, struct expression *arg3)
 {
   return this->beneath->can_accel_watchpoint_condition (arg0, arg1, arg2, arg3);
 }
 
-int
+bool
 dummy_target::can_accel_watchpoint_condition (CORE_ADDR arg0, int arg1, int arg2, struct expression *arg3)
 {
-  return 0;
+  return false;
 }
 
-int
+bool
 debug_target::can_accel_watchpoint_condition (CORE_ADDR arg0, int arg1, int arg2, struct expression *arg3)
 {
-  int result;
+  bool result;
   fprintf_unfiltered (gdb_stdlog, "-> %s->can_accel_watchpoint_condition (...)\n", this->beneath->shortname ());
   result = this->beneath->can_accel_watchpoint_condition (arg0, arg1, arg2, arg3);
   fprintf_unfiltered (gdb_stdlog, "<- %s->can_accel_watchpoint_condition (", this->beneath->shortname ());
@@ -1156,7 +1156,7 @@ debug_target::can_accel_watchpoint_condition (CORE_ADDR arg0, int arg1, int arg2
   fputs_unfiltered (", ", gdb_stdlog);
   target_debug_print_struct_expression_p (arg3);
   fputs_unfiltered (") = ", gdb_stdlog);
-  target_debug_print_int (result);
+  target_debug_print_bool (result);
   fputs_unfiltered ("\n", gdb_stdlog);
   return result;
 }
@@ -1223,7 +1223,7 @@ target_ops::supports_terminal_ours ()
 bool
 dummy_target::supports_terminal_ours ()
 {
-  return 0;
+  return false;
 }
 
 bool
@@ -1735,28 +1735,28 @@ debug_target::program_signals (int arg0, unsigned char * arg1)
   fputs_unfiltered (")\n", gdb_stdlog);
 }
 
-int
+bool
 target_ops::thread_alive (ptid_t arg0)
 {
   return this->beneath->thread_alive (arg0);
 }
 
-int
+bool
 dummy_target::thread_alive (ptid_t arg0)
 {
-  return 0;
+  return false;
 }
 
-int
+bool
 debug_target::thread_alive (ptid_t arg0)
 {
-  int result;
+  bool result;
   fprintf_unfiltered (gdb_stdlog, "-> %s->thread_alive (...)\n", this->beneath->shortname ());
   result = this->beneath->thread_alive (arg0);
   fprintf_unfiltered (gdb_stdlog, "<- %s->thread_alive (", this->beneath->shortname ());
   target_debug_print_ptid_t (arg0);
   fputs_unfiltered (") = ", gdb_stdlog);
-  target_debug_print_int (result);
+  target_debug_print_bool (result);
   fputs_unfiltered ("\n", gdb_stdlog);
   return result;
 }
@@ -2097,52 +2097,52 @@ debug_target::attach_no_wait ()
   return result;
 }
 
-int
+bool
 target_ops::can_async_p ()
 {
   return this->beneath->can_async_p ();
 }
 
-int
+bool
 dummy_target::can_async_p ()
 {
-  return 0;
+  return false;
 }
 
-int
+bool
 debug_target::can_async_p ()
 {
-  int result;
+  bool result;
   fprintf_unfiltered (gdb_stdlog, "-> %s->can_async_p (...)\n", this->beneath->shortname ());
   result = this->beneath->can_async_p ();
   fprintf_unfiltered (gdb_stdlog, "<- %s->can_async_p (", this->beneath->shortname ());
   fputs_unfiltered (") = ", gdb_stdlog);
-  target_debug_print_int (result);
+  target_debug_print_bool (result);
   fputs_unfiltered ("\n", gdb_stdlog);
   return result;
 }
 
-int
+bool
 target_ops::is_async_p ()
 {
   return this->beneath->is_async_p ();
 }
 
-int
+bool
 dummy_target::is_async_p ()
 {
-  return 0;
+  return false;
 }
 
-int
+bool
 debug_target::is_async_p ()
 {
-  int result;
+  bool result;
   fprintf_unfiltered (gdb_stdlog, "-> %s->is_async_p (...)\n", this->beneath->shortname ());
   result = this->beneath->is_async_p ();
   fprintf_unfiltered (gdb_stdlog, "<- %s->is_async_p (", this->beneath->shortname ());
   fputs_unfiltered (") = ", gdb_stdlog);
-  target_debug_print_int (result);
+  target_debug_print_bool (result);
   fputs_unfiltered ("\n", gdb_stdlog);
   return result;
 }
@@ -2190,52 +2190,52 @@ debug_target::thread_events (int arg0)
   fputs_unfiltered (")\n", gdb_stdlog);
 }
 
-int
+bool
 target_ops::supports_non_stop ()
 {
   return this->beneath->supports_non_stop ();
 }
 
-int
+bool
 dummy_target::supports_non_stop ()
 {
-  return 0;
+  return false;
 }
 
-int
+bool
 debug_target::supports_non_stop ()
 {
-  int result;
+  bool result;
   fprintf_unfiltered (gdb_stdlog, "-> %s->supports_non_stop (...)\n", this->beneath->shortname ());
   result = this->beneath->supports_non_stop ();
   fprintf_unfiltered (gdb_stdlog, "<- %s->supports_non_stop (", this->beneath->shortname ());
   fputs_unfiltered (") = ", gdb_stdlog);
-  target_debug_print_int (result);
+  target_debug_print_bool (result);
   fputs_unfiltered ("\n", gdb_stdlog);
   return result;
 }
 
-int
+bool
 target_ops::always_non_stop_p ()
 {
   return this->beneath->always_non_stop_p ();
 }
 
-int
+bool
 dummy_target::always_non_stop_p ()
 {
-  return 0;
+  return false;
 }
 
-int
+bool
 debug_target::always_non_stop_p ()
 {
-  int result;
+  bool result;
   fprintf_unfiltered (gdb_stdlog, "-> %s->always_non_stop_p (...)\n", this->beneath->shortname ());
   result = this->beneath->always_non_stop_p ();
   fprintf_unfiltered (gdb_stdlog, "<- %s->always_non_stop_p (", this->beneath->shortname ());
   fputs_unfiltered (") = ", gdb_stdlog);
-  target_debug_print_int (result);
+  target_debug_print_bool (result);
   fputs_unfiltered ("\n", gdb_stdlog);
   return result;
 }
@@ -2630,27 +2630,27 @@ debug_target::search_memory (CORE_ADDR arg0, ULONGEST arg1, const gdb_byte *arg2
   return result;
 }
 
-int
+bool
 target_ops::can_execute_reverse ()
 {
   return this->beneath->can_execute_reverse ();
 }
 
-int
+bool
 dummy_target::can_execute_reverse ()
 {
-  return 0;
+  return false;
 }
 
-int
+bool
 debug_target::can_execute_reverse ()
 {
-  int result;
+  bool result;
   fprintf_unfiltered (gdb_stdlog, "-> %s->can_execute_reverse (...)\n", this->beneath->shortname ());
   result = this->beneath->can_execute_reverse ();
   fprintf_unfiltered (gdb_stdlog, "<- %s->can_execute_reverse (", this->beneath->shortname ());
   fputs_unfiltered (") = ", gdb_stdlog);
-  target_debug_print_int (result);
+  target_debug_print_bool (result);
   fputs_unfiltered ("\n", gdb_stdlog);
   return result;
 }
@@ -2680,152 +2680,152 @@ debug_target::execution_direction ()
   return result;
 }
 
-int
+bool
 target_ops::supports_multi_process ()
 {
   return this->beneath->supports_multi_process ();
 }
 
-int
+bool
 dummy_target::supports_multi_process ()
 {
-  return 0;
+  return false;
 }
 
-int
+bool
 debug_target::supports_multi_process ()
 {
-  int result;
+  bool result;
   fprintf_unfiltered (gdb_stdlog, "-> %s->supports_multi_process (...)\n", this->beneath->shortname ());
   result = this->beneath->supports_multi_process ();
   fprintf_unfiltered (gdb_stdlog, "<- %s->supports_multi_process (", this->beneath->shortname ());
   fputs_unfiltered (") = ", gdb_stdlog);
-  target_debug_print_int (result);
+  target_debug_print_bool (result);
   fputs_unfiltered ("\n", gdb_stdlog);
   return result;
 }
 
-int
+bool
 target_ops::supports_enable_disable_tracepoint ()
 {
   return this->beneath->supports_enable_disable_tracepoint ();
 }
 
-int
+bool
 dummy_target::supports_enable_disable_tracepoint ()
 {
-  return 0;
+  return false;
 }
 
-int
+bool
 debug_target::supports_enable_disable_tracepoint ()
 {
-  int result;
+  bool result;
   fprintf_unfiltered (gdb_stdlog, "-> %s->supports_enable_disable_tracepoint (...)\n", this->beneath->shortname ());
   result = this->beneath->supports_enable_disable_tracepoint ();
   fprintf_unfiltered (gdb_stdlog, "<- %s->supports_enable_disable_tracepoint (", this->beneath->shortname ());
   fputs_unfiltered (") = ", gdb_stdlog);
-  target_debug_print_int (result);
+  target_debug_print_bool (result);
   fputs_unfiltered ("\n", gdb_stdlog);
   return result;
 }
 
-int
+bool
 target_ops::supports_disable_randomization ()
 {
   return this->beneath->supports_disable_randomization ();
 }
 
-int
+bool
 dummy_target::supports_disable_randomization ()
 {
   return find_default_supports_disable_randomization (this);
 }
 
-int
+bool
 debug_target::supports_disable_randomization ()
 {
-  int result;
+  bool result;
   fprintf_unfiltered (gdb_stdlog, "-> %s->supports_disable_randomization (...)\n", this->beneath->shortname ());
   result = this->beneath->supports_disable_randomization ();
   fprintf_unfiltered (gdb_stdlog, "<- %s->supports_disable_randomization (", this->beneath->shortname ());
   fputs_unfiltered (") = ", gdb_stdlog);
-  target_debug_print_int (result);
+  target_debug_print_bool (result);
   fputs_unfiltered ("\n", gdb_stdlog);
   return result;
 }
 
-int
+bool
 target_ops::supports_string_tracing ()
 {
   return this->beneath->supports_string_tracing ();
 }
 
-int
+bool
 dummy_target::supports_string_tracing ()
 {
-  return 0;
+  return false;
 }
 
-int
+bool
 debug_target::supports_string_tracing ()
 {
-  int result;
+  bool result;
   fprintf_unfiltered (gdb_stdlog, "-> %s->supports_string_tracing (...)\n", this->beneath->shortname ());
   result = this->beneath->supports_string_tracing ();
   fprintf_unfiltered (gdb_stdlog, "<- %s->supports_string_tracing (", this->beneath->shortname ());
   fputs_unfiltered (") = ", gdb_stdlog);
-  target_debug_print_int (result);
+  target_debug_print_bool (result);
   fputs_unfiltered ("\n", gdb_stdlog);
   return result;
 }
 
-int
+bool
 target_ops::supports_evaluation_of_breakpoint_conditions ()
 {
   return this->beneath->supports_evaluation_of_breakpoint_conditions ();
 }
 
-int
+bool
 dummy_target::supports_evaluation_of_breakpoint_conditions ()
 {
-  return 0;
+  return false;
 }
 
-int
+bool
 debug_target::supports_evaluation_of_breakpoint_conditions ()
 {
-  int result;
+  bool result;
   fprintf_unfiltered (gdb_stdlog, "-> %s->supports_evaluation_of_breakpoint_conditions (...)\n", this->beneath->shortname ());
   result = this->beneath->supports_evaluation_of_breakpoint_conditions ();
   fprintf_unfiltered (gdb_stdlog, "<- %s->supports_evaluation_of_breakpoint_conditions (", this->beneath->shortname ());
   fputs_unfiltered (") = ", gdb_stdlog);
-  target_debug_print_int (result);
+  target_debug_print_bool (result);
   fputs_unfiltered ("\n", gdb_stdlog);
   return result;
 }
 
-int
+bool
 target_ops::can_run_breakpoint_commands ()
 {
   return this->beneath->can_run_breakpoint_commands ();
 }
 
-int
+bool
 dummy_target::can_run_breakpoint_commands ()
 {
-  return 0;
+  return false;
 }
 
-int
+bool
 debug_target::can_run_breakpoint_commands ()
 {
-  int result;
+  bool result;
   fprintf_unfiltered (gdb_stdlog, "-> %s->can_run_breakpoint_commands (...)\n", this->beneath->shortname ());
   result = this->beneath->can_run_breakpoint_commands ();
   fprintf_unfiltered (gdb_stdlog, "<- %s->can_run_breakpoint_commands (", this->beneath->shortname ());
   fputs_unfiltered (") = ", gdb_stdlog);
-  target_debug_print_int (result);
+  target_debug_print_bool (result);
   fputs_unfiltered ("\n", gdb_stdlog);
   return result;
 }
@@ -2882,27 +2882,27 @@ debug_target::thread_address_space (ptid_t arg0)
   return result;
 }
 
-int
+bool
 target_ops::filesystem_is_local ()
 {
   return this->beneath->filesystem_is_local ();
 }
 
-int
+bool
 dummy_target::filesystem_is_local ()
 {
-  return 1;
+  return true;
 }
 
-int
+bool
 debug_target::filesystem_is_local ()
 {
-  int result;
+  bool result;
   fprintf_unfiltered (gdb_stdlog, "-> %s->filesystem_is_local (...)\n", this->beneath->shortname ());
   result = this->beneath->filesystem_is_local ();
   fprintf_unfiltered (gdb_stdlog, "<- %s->filesystem_is_local (", this->beneath->shortname ());
   fputs_unfiltered (") = ", gdb_stdlog);
-  target_debug_print_int (result);
+  target_debug_print_bool (result);
   fputs_unfiltered ("\n", gdb_stdlog);
   return result;
 }
@@ -2950,27 +2950,27 @@ debug_target::download_tracepoint (struct bp_location *arg0)
   fputs_unfiltered (")\n", gdb_stdlog);
 }
 
-int
+bool
 target_ops::can_download_tracepoint ()
 {
   return this->beneath->can_download_tracepoint ();
 }
 
-int
+bool
 dummy_target::can_download_tracepoint ()
 {
-  return 0;
+  return false;
 }
 
-int
+bool
 debug_target::can_download_tracepoint ()
 {
-  int result;
+  bool result;
   fprintf_unfiltered (gdb_stdlog, "-> %s->can_download_tracepoint (...)\n", this->beneath->shortname ());
   result = this->beneath->can_download_tracepoint ();
   fprintf_unfiltered (gdb_stdlog, "<- %s->can_download_tracepoint (", this->beneath->shortname ());
   fputs_unfiltered (") = ", gdb_stdlog);
-  target_debug_print_int (result);
+  target_debug_print_bool (result);
   fputs_unfiltered ("\n", gdb_stdlog);
   return result;
 }
@@ -3188,22 +3188,22 @@ debug_target::trace_find (enum trace_find_type arg0, int arg1, CORE_ADDR arg2, C
   return result;
 }
 
-int
+bool
 target_ops::get_trace_state_variable_value (int arg0, LONGEST *arg1)
 {
   return this->beneath->get_trace_state_variable_value (arg0, arg1);
 }
 
-int
+bool
 dummy_target::get_trace_state_variable_value (int arg0, LONGEST *arg1)
 {
-  return 0;
+  return false;
 }
 
-int
+bool
 debug_target::get_trace_state_variable_value (int arg0, LONGEST *arg1)
 {
-  int result;
+  bool result;
   fprintf_unfiltered (gdb_stdlog, "-> %s->get_trace_state_variable_value (...)\n", this->beneath->shortname ());
   result = this->beneath->get_trace_state_variable_value (arg0, arg1);
   fprintf_unfiltered (gdb_stdlog, "<- %s->get_trace_state_variable_value (", this->beneath->shortname ());
@@ -3211,7 +3211,7 @@ debug_target::get_trace_state_variable_value (int arg0, LONGEST *arg1)
   fputs_unfiltered (", ", gdb_stdlog);
   target_debug_print_LONGEST_p (arg1);
   fputs_unfiltered (") = ", gdb_stdlog);
-  target_debug_print_int (result);
+  target_debug_print_bool (result);
   fputs_unfiltered ("\n", gdb_stdlog);
   return result;
 }
@@ -3412,22 +3412,22 @@ debug_target::set_trace_buffer_size (LONGEST arg0)
   fputs_unfiltered (")\n", gdb_stdlog);
 }
 
-int
+bool
 target_ops::set_trace_notes (const char *arg0, const char *arg1, const char *arg2)
 {
   return this->beneath->set_trace_notes (arg0, arg1, arg2);
 }
 
-int
+bool
 dummy_target::set_trace_notes (const char *arg0, const char *arg1, const char *arg2)
 {
-  return 0;
+  return false;
 }
 
-int
+bool
 debug_target::set_trace_notes (const char *arg0, const char *arg1, const char *arg2)
 {
-  int result;
+  bool result;
   fprintf_unfiltered (gdb_stdlog, "-> %s->set_trace_notes (...)\n", this->beneath->shortname ());
   result = this->beneath->set_trace_notes (arg0, arg1, arg2);
   fprintf_unfiltered (gdb_stdlog, "<- %s->set_trace_notes (", this->beneath->shortname ());
@@ -3437,7 +3437,7 @@ debug_target::set_trace_notes (const char *arg0, const char *arg1, const char *a
   fputs_unfiltered (", ", gdb_stdlog);
   target_debug_print_const_char_p (arg2);
   fputs_unfiltered (") = ", gdb_stdlog);
-  target_debug_print_int (result);
+  target_debug_print_bool (result);
   fputs_unfiltered ("\n", gdb_stdlog);
   return result;
 }
@@ -3498,22 +3498,22 @@ debug_target::verify_memory (const gdb_byte *arg0, CORE_ADDR arg1, ULONGEST arg2
   return result;
 }
 
-int
+bool
 target_ops::get_tib_address (ptid_t arg0, CORE_ADDR *arg1)
 {
   return this->beneath->get_tib_address (arg0, arg1);
 }
 
-int
+bool
 dummy_target::get_tib_address (ptid_t arg0, CORE_ADDR *arg1)
 {
   tcomplain ();
 }
 
-int
+bool
 debug_target::get_tib_address (ptid_t arg0, CORE_ADDR *arg1)
 {
-  int result;
+  bool result;
   fprintf_unfiltered (gdb_stdlog, "-> %s->get_tib_address (...)\n", this->beneath->shortname ());
   result = this->beneath->get_tib_address (arg0, arg1);
   fprintf_unfiltered (gdb_stdlog, "<- %s->get_tib_address (", this->beneath->shortname ());
@@ -3521,7 +3521,7 @@ debug_target::get_tib_address (ptid_t arg0, CORE_ADDR *arg1)
   fputs_unfiltered (", ", gdb_stdlog);
   target_debug_print_CORE_ADDR_p (arg1);
   fputs_unfiltered (") = ", gdb_stdlog);
-  target_debug_print_int (result);
+  target_debug_print_bool (result);
   fputs_unfiltered ("\n", gdb_stdlog);
   return result;
 }
@@ -3625,53 +3625,53 @@ debug_target::traceframe_info ()
   return result;
 }
 
-int
-target_ops::use_agent (int arg0)
+bool
+target_ops::use_agent (bool arg0)
 {
   return this->beneath->use_agent (arg0);
 }
 
-int
-dummy_target::use_agent (int arg0)
+bool
+dummy_target::use_agent (bool arg0)
 {
   tcomplain ();
 }
 
-int
-debug_target::use_agent (int arg0)
+bool
+debug_target::use_agent (bool arg0)
 {
-  int result;
+  bool result;
   fprintf_unfiltered (gdb_stdlog, "-> %s->use_agent (...)\n", this->beneath->shortname ());
   result = this->beneath->use_agent (arg0);
   fprintf_unfiltered (gdb_stdlog, "<- %s->use_agent (", this->beneath->shortname ());
-  target_debug_print_int (arg0);
+  target_debug_print_bool (arg0);
   fputs_unfiltered (") = ", gdb_stdlog);
-  target_debug_print_int (result);
+  target_debug_print_bool (result);
   fputs_unfiltered ("\n", gdb_stdlog);
   return result;
 }
 
-int
+bool
 target_ops::can_use_agent ()
 {
   return this->beneath->can_use_agent ();
 }
 
-int
+bool
 dummy_target::can_use_agent ()
 {
-  return 0;
+  return false;
 }
 
-int
+bool
 debug_target::can_use_agent ()
 {
-  int result;
+  bool result;
   fprintf_unfiltered (gdb_stdlog, "-> %s->can_use_agent (...)\n", this->beneath->shortname ());
   result = this->beneath->can_use_agent ();
   fprintf_unfiltered (gdb_stdlog, "<- %s->can_use_agent (", this->beneath->shortname ());
   fputs_unfiltered (") = ", gdb_stdlog);
-  target_debug_print_int (result);
+  target_debug_print_bool (result);
   fputs_unfiltered ("\n", gdb_stdlog);
   return result;
 }
@@ -3938,48 +3938,48 @@ debug_target::delete_record ()
   fputs_unfiltered (")\n", gdb_stdlog);
 }
 
-int
+bool
 target_ops::record_is_replaying (ptid_t arg0)
 {
   return this->beneath->record_is_replaying (arg0);
 }
 
-int
+bool
 dummy_target::record_is_replaying (ptid_t arg0)
 {
-  return 0;
+  return false;
 }
 
-int
+bool
 debug_target::record_is_replaying (ptid_t arg0)
 {
-  int result;
+  bool result;
   fprintf_unfiltered (gdb_stdlog, "-> %s->record_is_replaying (...)\n", this->beneath->shortname ());
   result = this->beneath->record_is_replaying (arg0);
   fprintf_unfiltered (gdb_stdlog, "<- %s->record_is_replaying (", this->beneath->shortname ());
   target_debug_print_ptid_t (arg0);
   fputs_unfiltered (") = ", gdb_stdlog);
-  target_debug_print_int (result);
+  target_debug_print_bool (result);
   fputs_unfiltered ("\n", gdb_stdlog);
   return result;
 }
 
-int
+bool
 target_ops::record_will_replay (ptid_t arg0, int arg1)
 {
   return this->beneath->record_will_replay (arg0, arg1);
 }
 
-int
+bool
 dummy_target::record_will_replay (ptid_t arg0, int arg1)
 {
-  return 0;
+  return false;
 }
 
-int
+bool
 debug_target::record_will_replay (ptid_t arg0, int arg1)
 {
-  int result;
+  bool result;
   fprintf_unfiltered (gdb_stdlog, "-> %s->record_will_replay (...)\n", this->beneath->shortname ());
   result = this->beneath->record_will_replay (arg0, arg1);
   fprintf_unfiltered (gdb_stdlog, "<- %s->record_will_replay (", this->beneath->shortname ());
@@ -3987,7 +3987,7 @@ debug_target::record_will_replay (ptid_t arg0, int arg1)
   fputs_unfiltered (", ", gdb_stdlog);
   target_debug_print_int (arg1);
   fputs_unfiltered (") = ", gdb_stdlog);
-  target_debug_print_int (result);
+  target_debug_print_bool (result);
   fputs_unfiltered ("\n", gdb_stdlog);
   return result;
 }
@@ -4228,27 +4228,27 @@ debug_target::call_history_range (ULONGEST arg0, ULONGEST arg1, record_print_fla
   fputs_unfiltered (")\n", gdb_stdlog);
 }
 
-int
+bool
 target_ops::augmented_libraries_svr4_read ()
 {
   return this->beneath->augmented_libraries_svr4_read ();
 }
 
-int
+bool
 dummy_target::augmented_libraries_svr4_read ()
 {
-  return 0;
+  return false;
 }
 
-int
+bool
 debug_target::augmented_libraries_svr4_read ()
 {
-  int result;
+  bool result;
   fprintf_unfiltered (gdb_stdlog, "-> %s->augmented_libraries_svr4_read (...)\n", this->beneath->shortname ());
   result = this->beneath->augmented_libraries_svr4_read ();
   fprintf_unfiltered (gdb_stdlog, "<- %s->augmented_libraries_svr4_read (", this->beneath->shortname ());
   fputs_unfiltered (") = ", gdb_stdlog);
-  target_debug_print_int (result);
+  target_debug_print_bool (result);
   fputs_unfiltered ("\n", gdb_stdlog);
   return result;
 }
diff --git a/gdb/target.c b/gdb/target.c
index 022da5919a..3ed5537e2d 100644
--- a/gdb/target.c
+++ b/gdb/target.c
@@ -2650,10 +2650,10 @@ target_ops::create_inferior (const char *, const std::string &,
   gdb_assert_not_reached ("target_ops::create_inferior called");
 }
 
-int
+bool
 target_ops::can_run ()
 {
-  return 0;
+  return false;
 }
 
 int
diff --git a/gdb/target.h b/gdb/target.h
index f78eb459dc..cd49fce92b 100644
--- a/gdb/target.h
+++ b/gdb/target.h
@@ -482,11 +482,11 @@ struct target_ops
        done from the target, so GDB needs to be able to tell whether
        it should ignore the event and whether it should adjust the PC.
        See adjust_pc_after_break.  */
-    virtual int stopped_by_sw_breakpoint ()
-      TARGET_DEFAULT_RETURN (0);
+    virtual bool stopped_by_sw_breakpoint ()
+      TARGET_DEFAULT_RETURN (false);
     /* Returns true if the above method is supported.  */
-    virtual int supports_stopped_by_sw_breakpoint ()
-      TARGET_DEFAULT_RETURN (0);
+    virtual bool supports_stopped_by_sw_breakpoint ()
+      TARGET_DEFAULT_RETURN (false);
 
     /* Returns true if the target stopped for a hardware breakpoint.
        Likewise, if the target supports hardware breakpoints, this
@@ -495,11 +495,11 @@ struct target_ops
        require PC adjustment, GDB needs to be able to tell whether the
        hardware breakpoint event is a delayed event for a breakpoint
        that is already gone and should thus be ignored.  */
-    virtual int stopped_by_hw_breakpoint ()
-      TARGET_DEFAULT_RETURN (0);
+    virtual bool stopped_by_hw_breakpoint ()
+      TARGET_DEFAULT_RETURN (false);
     /* Returns true if the above method is supported.  */
-    virtual int supports_stopped_by_hw_breakpoint ()
-      TARGET_DEFAULT_RETURN (0);
+    virtual bool supports_stopped_by_hw_breakpoint ()
+      TARGET_DEFAULT_RETURN (false);
 
     virtual int can_use_hw_breakpoint (enum bptype, int, int)
       TARGET_DEFAULT_RETURN (0);
@@ -527,15 +527,15 @@ struct target_ops
     virtual int remove_mask_watchpoint (CORE_ADDR, CORE_ADDR,
 					enum target_hw_bp_type)
       TARGET_DEFAULT_RETURN (1);
-    virtual int stopped_by_watchpoint ()
-      TARGET_DEFAULT_RETURN (0);
+    virtual bool stopped_by_watchpoint ()
+      TARGET_DEFAULT_RETURN (false);
     virtual int have_steppable_watchpoint ()
-      TARGET_DEFAULT_RETURN (0);
+      TARGET_DEFAULT_RETURN (false);
     virtual bool have_continuable_watchpoint ()
-      TARGET_DEFAULT_RETURN (0);
-    virtual int stopped_data_address (CORE_ADDR *)
-      TARGET_DEFAULT_RETURN (0);
-    virtual int watchpoint_addr_within_range (CORE_ADDR, CORE_ADDR, int)
+      TARGET_DEFAULT_RETURN (false);
+    virtual bool stopped_data_address (CORE_ADDR *)
+      TARGET_DEFAULT_RETURN (false);
+    virtual bool watchpoint_addr_within_range (CORE_ADDR, CORE_ADDR, int)
       TARGET_DEFAULT_FUNC (default_watchpoint_addr_within_range);
 
     /* Documentation of this routine is provided with the corresponding
@@ -543,9 +543,9 @@ struct target_ops
     virtual int region_ok_for_hw_watchpoint (CORE_ADDR, int)
       TARGET_DEFAULT_FUNC (default_region_ok_for_hw_watchpoint);
 
-    virtual int can_accel_watchpoint_condition (CORE_ADDR, int, int,
-						struct expression *)
-      TARGET_DEFAULT_RETURN (0);
+    virtual bool can_accel_watchpoint_condition (CORE_ADDR, int, int,
+						 struct expression *)
+      TARGET_DEFAULT_RETURN (false);
     virtual int masked_watch_num_registers (CORE_ADDR, CORE_ADDR)
       TARGET_DEFAULT_RETURN (-1);
 
@@ -555,7 +555,7 @@ struct target_ops
       TARGET_DEFAULT_RETURN (-1);
 
     virtual bool supports_terminal_ours ()
-      TARGET_DEFAULT_RETURN (0);
+      TARGET_DEFAULT_RETURN (false);
     virtual void terminal_init ()
       TARGET_DEFAULT_IGNORE ();
     virtual void terminal_inferior ()
@@ -607,7 +607,7 @@ struct target_ops
     /* Note that can_run is special and can be invoked on an unpushed
        target.  Targets defining this method must also define
        to_can_async_p and to_supports_non_stop.  */
-    virtual int can_run ();
+    virtual bool can_run ();
 
     /* Documentation of this routine is provided with the corresponding
        target_* macro.  */
@@ -621,8 +621,8 @@ struct target_ops
 				  unsigned char * TARGET_DEBUG_PRINTER (target_debug_print_signals))
       TARGET_DEFAULT_IGNORE ();
 
-    virtual int thread_alive (ptid_t ptid)
-      TARGET_DEFAULT_RETURN (0);
+    virtual bool thread_alive (ptid_t ptid)
+      TARGET_DEFAULT_RETURN (false);
     virtual void update_thread_list ()
       TARGET_DEFAULT_IGNORE ();
     virtual const char *pid_to_str (ptid_t)
@@ -652,11 +652,11 @@ struct target_ops
     enum strata to_stratum;
 
     /* Provide default values for all "must have" methods.  */
-    virtual int has_all_memory () { return 0; }
-    virtual int has_memory () { return 0; }
-    virtual int has_stack () { return 0; }
-    virtual int has_registers () { return 0; }
-    virtual int has_execution (ptid_t) { return 0; }
+    virtual bool has_all_memory () { return false; }
+    virtual bool has_memory () { return false; }
+    virtual bool has_stack () { return false; }
+    virtual bool has_registers () { return false; }
+    virtual bool has_execution (ptid_t) { return false; }
 
     /* Control thread execution.  */
     virtual thread_control_capabilities get_thread_control_capabilities ()
@@ -665,22 +665,22 @@ struct target_ops
       TARGET_DEFAULT_RETURN (0);
     /* This method must be implemented in some situations.  See the
        comment on 'can_run'.  */
-    virtual int can_async_p ()
-      TARGET_DEFAULT_RETURN (0);
-    virtual int is_async_p ()
-      TARGET_DEFAULT_RETURN (0);
+    virtual bool can_async_p ()
+      TARGET_DEFAULT_RETURN (false);
+    virtual bool is_async_p ()
+      TARGET_DEFAULT_RETURN (false);
     virtual void async (int)
       TARGET_DEFAULT_NORETURN (tcomplain ());
     virtual void thread_events (int)
       TARGET_DEFAULT_IGNORE ();
     /* This method must be implemented in some situations.  See the
        comment on 'can_run'.  */
-    virtual int supports_non_stop ()
-      TARGET_DEFAULT_RETURN (0);
+    virtual bool supports_non_stop ()
+      TARGET_DEFAULT_RETURN (false);
     /* Return true if the target operates in non-stop mode even with
        "set non-stop off".  */
-    virtual int always_non_stop_p ()
-      TARGET_DEFAULT_RETURN (0);
+    virtual bool always_non_stop_p ()
+      TARGET_DEFAULT_RETURN (false);
     /* find_memory_regions support method for gcore */
     virtual int find_memory_regions (find_memory_region_ftype func, void *data)
       TARGET_DEFAULT_FUNC (dummy_find_memory_regions);
@@ -815,8 +815,8 @@ struct target_ops
       TARGET_DEFAULT_FUNC (default_search_memory);
 
     /* Can target execute in reverse?  */
-    virtual int can_execute_reverse ()
-      TARGET_DEFAULT_RETURN (0);
+    virtual bool can_execute_reverse ()
+      TARGET_DEFAULT_RETURN (false);
 
     /* The direction the target is currently executing.  Must be
        implemented on targets that support reverse execution and async
@@ -826,31 +826,31 @@ struct target_ops
 
     /* Does this target support debugging multiple processes
        simultaneously?  */
-    virtual int supports_multi_process ()
-      TARGET_DEFAULT_RETURN (0);
+    virtual bool supports_multi_process ()
+      TARGET_DEFAULT_RETURN (false);
 
     /* Does this target support enabling and disabling tracepoints while a trace
        experiment is running?  */
-    virtual int supports_enable_disable_tracepoint ()
-      TARGET_DEFAULT_RETURN (0);
+    virtual bool supports_enable_disable_tracepoint ()
+      TARGET_DEFAULT_RETURN (false);
 
     /* Does this target support disabling address space randomization?  */
-    virtual int supports_disable_randomization ()
+    virtual bool supports_disable_randomization ()
       TARGET_DEFAULT_FUNC (find_default_supports_disable_randomization);
 
     /* Does this target support the tracenz bytecode for string collection?  */
-    virtual int supports_string_tracing ()
-      TARGET_DEFAULT_RETURN (0);
+    virtual bool supports_string_tracing ()
+      TARGET_DEFAULT_RETURN (false);
 
     /* Does this target support evaluation of breakpoint conditions on its
        end?  */
-    virtual int supports_evaluation_of_breakpoint_conditions ()
-      TARGET_DEFAULT_RETURN (0);
+    virtual bool supports_evaluation_of_breakpoint_conditions ()
+      TARGET_DEFAULT_RETURN (false);
 
     /* Does this target support evaluation of breakpoint commands on its
        end?  */
-    virtual int can_run_breakpoint_commands ()
-      TARGET_DEFAULT_RETURN (0);
+    virtual bool can_run_breakpoint_commands ()
+      TARGET_DEFAULT_RETURN (false);
 
     /* Determine current architecture of thread PTID.
 
@@ -876,8 +876,8 @@ struct target_ops
 
     /* Return nonzero if the filesystem seen by the current inferior
        is the local filesystem, zero otherwise.  */
-    virtual int filesystem_is_local ()
-      TARGET_DEFAULT_RETURN (1);
+    virtual bool filesystem_is_local ()
+      TARGET_DEFAULT_RETURN (true);
 
     /* Open FILENAME on the target, in the filesystem as seen by INF,
        using FLAGS and MODE.  If INF is NULL, use the filesystem seen
@@ -944,8 +944,8 @@ struct target_ops
 
     /* Is the target able to download tracepoint locations in current
        state?  */
-    virtual int can_download_tracepoint ()
-      TARGET_DEFAULT_RETURN (0);
+    virtual bool can_download_tracepoint ()
+      TARGET_DEFAULT_RETURN (false);
 
     /* Send full details of a trace state variable to the target.  */
     virtual void download_trace_state_variable (const trace_state_variable &tsv)
@@ -993,8 +993,8 @@ struct target_ops
     /* Get the value of the trace state variable number TSV, returning
        1 if the value is known and writing the value itself into the
        location pointed to by VAL, else returning 0.  */
-    virtual int get_trace_state_variable_value (int tsv, LONGEST *val)
-      TARGET_DEFAULT_RETURN (0);
+    virtual bool get_trace_state_variable_value (int tsv, LONGEST *val)
+      TARGET_DEFAULT_RETURN (false);
 
     virtual int save_trace_data (const char *filename)
       TARGET_DEFAULT_NORETURN (tcomplain ());
@@ -1028,9 +1028,9 @@ struct target_ops
 
     /* Add/change textual notes about the trace run, returning 1 if
        successful, 0 otherwise.  */
-    virtual int set_trace_notes (const char *user, const char *notes,
-				 const char *stopnotes)
-      TARGET_DEFAULT_RETURN (0);
+    virtual bool set_trace_notes (const char *user, const char *notes,
+				  const char *stopnotes)
+      TARGET_DEFAULT_RETURN (false);
 
     /* Return the processor core that thread PTID was last seen on.
        This information is updated only when:
@@ -1052,7 +1052,7 @@ struct target_ops
 
     /* Return the address of the start of the Thread Information Block
        a Windows OS specific feature.  */
-    virtual int get_tib_address (ptid_t ptid, CORE_ADDR *addr)
+    virtual bool get_tib_address (ptid_t ptid, CORE_ADDR *addr)
       TARGET_DEFAULT_NORETURN (tcomplain ());
 
     /* Send the new settings of write permission variables.  */
@@ -1078,14 +1078,14 @@ struct target_ops
     virtual traceframe_info_up traceframe_info ()
       TARGET_DEFAULT_NORETURN (tcomplain ());
 
-    /* Ask the target to use or not to use agent according to USE.  Return 1
-       successful, 0 otherwise.  */
-    virtual int use_agent (int use)
+    /* Ask the target to use or not to use agent according to USE.
+       Return true if successful, false otherwise.  */
+    virtual bool use_agent (bool use)
       TARGET_DEFAULT_NORETURN (tcomplain ());
 
     /* Is the target able to use agent in current state?  */
-    virtual int can_use_agent ()
-      TARGET_DEFAULT_RETURN (0);
+    virtual bool can_use_agent ()
+      TARGET_DEFAULT_RETURN (false);
 
     /* Enable branch tracing for PTID using CONF configuration.
        Return a branch trace target information struct for reading and for
@@ -1140,13 +1140,13 @@ struct target_ops
       TARGET_DEFAULT_NORETURN (tcomplain ());
 
     /* Query if the record target is currently replaying PTID.  */
-    virtual int record_is_replaying (ptid_t ptid)
-      TARGET_DEFAULT_RETURN (0);
+    virtual bool record_is_replaying (ptid_t ptid)
+      TARGET_DEFAULT_RETURN (false);
 
     /* Query if the record target will replay PTID if it were resumed in
        execution direction DIR.  */
-    virtual int record_will_replay (ptid_t ptid, int dir)
-      TARGET_DEFAULT_RETURN (0);
+    virtual bool record_will_replay (ptid_t ptid, int dir)
+      TARGET_DEFAULT_RETURN (false);
 
     /* Stop replaying.  */
     virtual void record_stop_replaying ()
@@ -1203,10 +1203,10 @@ struct target_ops
     virtual void call_history_range (ULONGEST begin, ULONGEST end, record_print_flags flags)
       TARGET_DEFAULT_NORETURN (tcomplain ());
 
-    /* Nonzero if TARGET_OBJECT_LIBRARIES_SVR4 may be read with a
+    /* True if TARGET_OBJECT_LIBRARIES_SVR4 may be read with a
        non-empty annex.  */
-    virtual int augmented_libraries_svr4_read ()
-      TARGET_DEFAULT_RETURN (0);
+    virtual bool augmented_libraries_svr4_read ()
+      TARGET_DEFAULT_RETURN (false);
 
     /* Those unwinders are tried before any other arch unwinders.  If
        SELF doesn't have unwinders, it should delegate to the
@@ -2481,19 +2481,19 @@ public:
     return NULL;
   }
 
-  int has_registers () override
+  bool has_registers () override
   {
-    return 1;
+    return true;
   }
 
-  int has_stack () override
+  bool has_stack () override
   {
-    return 1;
+    return true;
   }
 
-  int has_memory () override
+  bool has_memory () override
   {
-    return 1;
+    return true;
   }
 
   void prepare_to_store (regcache *regs) override
diff --git a/gdb/tracefile-tfile.c b/gdb/tracefile-tfile.c
index af8e3bd83b..d224ad9760 100644
--- a/gdb/tracefile-tfile.c
+++ b/gdb/tracefile-tfile.c
@@ -67,7 +67,7 @@ Use a trace file as a target.  Specify the filename of the trace file.");
   void files_info () override;
   int trace_find (enum trace_find_type type, int num,
 			  CORE_ADDR addr1, CORE_ADDR addr2, int *tpp) override;
-  int get_trace_state_variable_value (int tsv, LONGEST *val) override;
+  bool get_trace_state_variable_value (int tsv, LONGEST *val) override;
   traceframe_info_up traceframe_info () override;
 
   void get_tracepoint_status (struct breakpoint *tp,
@@ -1033,11 +1033,11 @@ tfile_target::xfer_partial (enum target_object object,
 /* Iterate through the blocks of a trace frame, looking for a 'V'
    block with a matching tsv number.  */
 
-int
+bool
 tfile_target::get_trace_state_variable_value (int tsvnum, LONGEST *val)
 {
   int pos;
-  int found = 0;
+  bool found = false;
 
   /* Iterate over blocks in current frame and find the last 'V'
      block in which tsv number is TSVNUM.  In one trace frame, there
@@ -1058,7 +1058,7 @@ tfile_target::get_trace_state_variable_value (int tsvnum, LONGEST *val)
 	  *val = extract_signed_integer ((gdb_byte *) val, 8,
 					 gdbarch_byte_order
 					 (target_gdbarch ()));
-	  found = 1;
+	  found = true;
 	}
       pos += (4 + 8);
     }
diff --git a/gdb/tracefile.c b/gdb/tracefile.c
index 9c9c75398e..f7e69f2df6 100644
--- a/gdb/tracefile.c
+++ b/gdb/tracefile.c
@@ -425,7 +425,7 @@ tracefile_fetch_registers (struct regcache *regcache, int regno)
 
 /* This is the implementation of target_ops method to_has_all_memory.  */
 
-int
+bool
 tracefile_target::has_all_memory ()
 {
   return 1;
@@ -433,7 +433,7 @@ tracefile_target::has_all_memory ()
 
 /* This is the implementation of target_ops method to_has_memory.  */
 
-int
+bool
 tracefile_target::has_memory ()
 {
   return 1;
@@ -443,7 +443,7 @@ tracefile_target::has_memory ()
    The target has a stack when GDB has already selected one trace
    frame.  */
 
-int
+bool
 tracefile_target::has_stack ()
 {
   return get_traceframe_number () != -1;
@@ -453,7 +453,7 @@ tracefile_target::has_stack ()
    The target has registers when GDB has already selected one trace
    frame.  */
 
-int
+bool
 tracefile_target::has_registers ()
 {
   return get_traceframe_number () != -1;
@@ -462,7 +462,7 @@ tracefile_target::has_registers ()
 /* This is the implementation of target_ops method to_thread_alive.
    tracefile has one thread faked by GDB.  */
 
-int
+bool
 tracefile_target::thread_alive (ptid_t ptid)
 {
   return 1;
diff --git a/gdb/tracefile.h b/gdb/tracefile.h
index accd038ebd..47f8bee8f2 100644
--- a/gdb/tracefile.h
+++ b/gdb/tracefile.h
@@ -122,11 +122,11 @@ public:
   tracefile_target ();
 
   int get_trace_status (trace_status *ts) override;
-  int has_all_memory () override;
-  int has_memory () override;
-  int has_stack () override;
-  int has_registers () override;
-  int thread_alive (ptid_t ptid) override;
+  bool has_all_memory () override;
+  bool has_memory () override;
+  bool has_stack () override;
+  bool has_registers () override;
+  bool thread_alive (ptid_t ptid) override;
 };
 
 extern void tracefile_fetch_registers (struct regcache *regcache, int regno);
diff --git a/gdb/windows-nat.c b/gdb/windows-nat.c
index 589ef47c67..f5a66c1f1c 100644
--- a/gdb/windows-nat.c
+++ b/gdb/windows-nat.c
@@ -333,7 +333,7 @@ struct windows_nat_target final : public x86_nat_target<inf_child_target>
 
   void mourn_inferior () override;
 
-  int thread_alive (ptid_t ptid) override;
+  bool thread_alive (ptid_t ptid) override;
 
   const char *pid_to_str (ptid_t) override;
 
@@ -343,7 +343,7 @@ struct windows_nat_target final : public x86_nat_target<inf_child_target>
 
   ptid_t get_ada_task_ptid (long lwp, long thread) override;
 
-  int get_tib_address (ptid_t ptid, CORE_ADDR *addr) override;
+  bool get_tib_address (ptid_t ptid, CORE_ADDR *addr) override;
 
   const char *thread_name (struct thread_info *) override;
 };
@@ -2975,19 +2975,19 @@ windows_nat_target::xfer_partial (enum target_object object,
 /* Provide thread local base, i.e. Thread Information Block address.
    Returns 1 if ptid is found and sets *ADDR to thread_local_base.  */
 
-int
+bool
 windows_nat_target::get_tib_address (ptid_t ptid, CORE_ADDR *addr)
 {
   windows_thread_info *th;
 
   th = thread_rec (ptid_get_tid (ptid), 0);
   if (th == NULL)
-    return 0;
+    return false;
 
   if (addr != NULL)
     *addr = th->thread_local_base;
 
-  return 1;
+  return true;
 }
 
 ptid_t
@@ -3156,7 +3156,7 @@ cygwin_get_dr7 (void)
    by "polling" it.  If WaitForSingleObject returns WAIT_OBJECT_0
    it means that the thread has died.  Otherwise it is assumed to be alive.  */
 
-int
+bool
 windows_nat_target::thread_alive (ptid_t ptid)
 {
   int tid;
@@ -3164,8 +3164,7 @@ windows_nat_target::thread_alive (ptid_t ptid)
   gdb_assert (ptid_get_tid (ptid) != 0);
   tid = ptid_get_tid (ptid);
 
-  return WaitForSingleObject (thread_rec (tid, FALSE)->h, 0) == WAIT_OBJECT_0
-    ? FALSE : TRUE;
+  return WaitForSingleObject (thread_rec (tid, FALSE)->h, 0) != WAIT_OBJECT_0;
 }
 
 void
diff --git a/gdb/x86-linux-nat.h b/gdb/x86-linux-nat.h
index 0bafaaa71f..7cbb27184a 100644
--- a/gdb/x86-linux-nat.h
+++ b/gdb/x86-linux-nat.h
@@ -47,16 +47,16 @@ struct x86_linux_nat_target : public x86_nat_target<linux_nat_target>
      stopped-by-watchpoint info as soon as an lwp stops (via the low_
      methods) and caches the result, to be returned via the normal
      non-low methods.  */
-  int stopped_by_watchpoint () override
+  bool stopped_by_watchpoint () override
   { return linux_nat_target::stopped_by_watchpoint (); }
 
-  int stopped_data_address (CORE_ADDR *addr_p) override
+  bool stopped_data_address (CORE_ADDR *addr_p) override
   { return linux_nat_target::stopped_data_address (addr_p); }
 
-  int low_stopped_by_watchpoint () override
+  bool low_stopped_by_watchpoint () override
   { return x86_nat_target::stopped_by_watchpoint (); }
 
-  int low_stopped_data_address (CORE_ADDR *addr_p) override
+  bool low_stopped_data_address (CORE_ADDR *addr_p) override
   { return x86_nat_target::stopped_data_address (addr_p); }
 };
 
diff --git a/gdb/x86-nat.h b/gdb/x86-nat.h
index 8ad1821360..cc27fa43b4 100644
--- a/gdb/x86-nat.h
+++ b/gdb/x86-nat.h
@@ -103,16 +103,16 @@ struct x86_nat_target : public BaseTarget
 			    struct bp_target_info *bp_tgt) override
   { return x86_remove_hw_breakpoint (gdbarch, bp_tgt); }
 
-  int stopped_by_watchpoint () override
+  bool stopped_by_watchpoint () override
   { return x86_stopped_by_watchpoint (); }
 
-  int stopped_data_address (CORE_ADDR *addr_p) override
+  bool stopped_data_address (CORE_ADDR *addr_p) override
   { return x86_stopped_data_address (addr_p); }
 
   /* A target must provide an implementation of the
      "supports_stopped_by_hw_breakpoint" target method before this
      callback will be used.  */
-  int stopped_by_hw_breakpoint () override
+  bool stopped_by_hw_breakpoint () override
   { return x86_stopped_by_hw_breakpoint (); }
 };
 
