diff --git a/sim/common/sim-core.h b/sim/common/sim-core.h
index 34826f76edb8..bad69876e4f6 100644
--- a/sim/common/sim-core.h
+++ b/sim/common/sim-core.h
@@ -40,7 +40,7 @@ typedef void (SIM_CORE_SIGNAL_FN)
      (SIM_DESC sd, sim_cpu *cpu, sim_cia cia, unsigned map, int nr_bytes,
       address_word addr, transfer_type transfer, sim_core_signals sig);
 
-extern SIM_CORE_SIGNAL_FN sim_core_signal;
+extern SIM_CORE_SIGNAL_FN sim_core_signal ATTRIBUTE_NORETURN;
 
 
 /* basic types */
diff --git a/sim/cris/sim-main.h b/sim/cris/sim-main.h
index abebe2bafc1f..8fa6ff522bcc 100644
--- a/sim/cris/sim-main.h
+++ b/sim/cris/sim-main.h
@@ -201,7 +201,7 @@ struct cris_sim_cpu {
 /* Misc.  */
 
 /* Catch address exceptions.  */
-extern SIM_CORE_SIGNAL_FN cris_core_signal;
+extern SIM_CORE_SIGNAL_FN cris_core_signal ATTRIBUTE_NORETURN;
 #define SIM_CORE_SIGNAL(SD,CPU,CIA,MAP,NR_BYTES,ADDR,TRANSFER,ERROR) \
 cris_core_signal ((SD), (CPU), (CIA), (MAP), (NR_BYTES), (ADDR), \
 		  (TRANSFER), (ERROR))
diff --git a/sim/frv/sim-main.h b/sim/frv/sim-main.h
index f2fbcce2b214..b9f99fb3dede 100644
--- a/sim/frv/sim-main.h
+++ b/sim/frv/sim-main.h
@@ -102,7 +102,7 @@ struct frv_sim_cpu {
 /* Misc.  */
 
 /* Catch address exceptions.  */
-extern SIM_CORE_SIGNAL_FN frv_core_signal;
+extern SIM_CORE_SIGNAL_FN frv_core_signal ATTRIBUTE_NORETURN;
 #define SIM_CORE_SIGNAL(SD,CPU,CIA,MAP,NR_BYTES,ADDR,TRANSFER,ERROR) \
 frv_core_signal ((SD), (CPU), (CIA), (MAP), (NR_BYTES), (ADDR), \
 		  (TRANSFER), (ERROR))
diff --git a/sim/iq2000/sim-main.h b/sim/iq2000/sim-main.h
index dcd7ed4682f8..82865943e3bc 100644
--- a/sim/iq2000/sim-main.h
+++ b/sim/iq2000/sim-main.h
@@ -37,7 +37,7 @@ struct iq2000_sim_cpu {
 /* Misc.  */
 
 /* Catch address exceptions.  */
-extern SIM_CORE_SIGNAL_FN iq2000_core_signal;
+extern SIM_CORE_SIGNAL_FN iq2000_core_signal ATTRIBUTE_NORETURN;
 #define SIM_CORE_SIGNAL(SD,CPU,CIA,MAP,NR_BYTES,ADDR,TRANSFER,ERROR) \
 iq2000_core_signal ((SD), (CPU), (CIA), (MAP), (NR_BYTES), (ADDR), \
 		  (TRANSFER), (ERROR))
diff --git a/sim/lm32/sim-main.h b/sim/lm32/sim-main.h
index e0e967c4233b..c252dc8f6411 100644
--- a/sim/lm32/sim-main.h
+++ b/sim/lm32/sim-main.h
@@ -51,7 +51,7 @@ struct lm32_sim_cpu
 /* Misc.  */
 
 /* Catch address exceptions.  */
-extern SIM_CORE_SIGNAL_FN lm32_core_signal;
+extern SIM_CORE_SIGNAL_FN lm32_core_signal ATTRIBUTE_NORETURN;
 #define SIM_CORE_SIGNAL(SD,CPU,CIA,MAP,NR_BYTES,ADDR,TRANSFER,ERROR) \
 lm32_core_signal ((SD), (CPU), (CIA), (MAP), (NR_BYTES), (ADDR), \
 		  (TRANSFER), (ERROR))
diff --git a/sim/m32r/sim-main.h b/sim/m32r/sim-main.h
index 89502f2240e3..31758a153a10 100644
--- a/sim/m32r/sim-main.h
+++ b/sim/m32r/sim-main.h
@@ -21,7 +21,7 @@
 /* Misc.  */
 
 /* Catch address exceptions.  */
-extern SIM_CORE_SIGNAL_FN m32r_core_signal;
+extern SIM_CORE_SIGNAL_FN m32r_core_signal ATTRIBUTE_NORETURN;
 #define SIM_CORE_SIGNAL(SD,CPU,CIA,MAP,NR_BYTES,ADDR,TRANSFER,ERROR) \
 m32r_core_signal ((SD), (CPU), (CIA), (MAP), (NR_BYTES), (ADDR), \
 		  (TRANSFER), (ERROR))
diff --git a/sim/m4/sim_ac_option_warnings.m4 b/sim/m4/sim_ac_option_warnings.m4
index 9f1487f93d0c..3da1c6a2e4a8 100644
--- a/sim/m4/sim_ac_option_warnings.m4
+++ b/sim/m4/sim_ac_option_warnings.m4
@@ -45,6 +45,7 @@ dnl C++ -Wno-mismatched-tags
 -Wno-error=deprecated-register
 dnl C++ -Wsuggest-override
 -Wduplicated-cond
+dnl -Wshadow=local
 dnl C++ -Wdeprecated-copy
 dnl C++ -Wdeprecated-copy-dtor
 dnl C++ -Wredundant-move
diff --git a/sim/mips/interp.c b/sim/mips/interp.c
index cb650a552483..255807f67906 100644
--- a/sim/mips/interp.c
+++ b/sim/mips/interp.c
@@ -2498,7 +2498,8 @@ mips_core_signal (SIM_DESC sd,
 		      (unsigned long) addr, (unsigned long) ip);
       COP0_BADVADDR = addr;
       SignalExceptionDataReference();
-      break;
+      /* Shouldn't actually be reached.  */
+      abort ();
 
     case sim_core_unaligned_signal:
       sim_io_eprintf (sd, "mips-core: %d byte %s to unaligned address 0x%lx at 0x%lx\n",
@@ -2509,7 +2510,8 @@ mips_core_signal (SIM_DESC sd,
 	SignalExceptionAddressLoad();
       else
 	SignalExceptionAddressStore();
-      break;
+      /* Shouldn't actually be reached.  */
+      abort ();
 
     default:
       sim_engine_abort (sd, cpu, cia,
diff --git a/sim/mips/sim-main.h b/sim/mips/sim-main.h
index d5a0dc81b628..5d358564f281 100644
--- a/sim/mips/sim-main.h
+++ b/sim/mips/sim-main.h
@@ -1038,7 +1038,7 @@ extern int DSPLO_REGNUM[4];
 extern int DSPHI_REGNUM[4];
 
 INLINE_SIM_MAIN (void) pending_tick (SIM_DESC sd, sim_cpu *cpu, address_word cia);
-extern SIM_CORE_SIGNAL_FN mips_core_signal;
+extern SIM_CORE_SIGNAL_FN mips_core_signal ATTRIBUTE_NORETURN;
 
 char* pr_addr (address_word addr);
 char* pr_uword64 (uword64 addr);
diff --git a/sim/mn10300/mn10300-sim.h b/sim/mn10300/mn10300-sim.h
index 3eadc0fe1780..493df3893e99 100644
--- a/sim/mn10300/mn10300-sim.h
+++ b/sim/mn10300/mn10300-sim.h
@@ -196,7 +196,8 @@ INLINE_SIM_MAIN (void) genericOr (uint32_t source, uint32_t destReg);
 INLINE_SIM_MAIN (void) genericXor (uint32_t source, uint32_t destReg);
 INLINE_SIM_MAIN (void) genericBtst (uint32_t leftOpnd, uint32_t rightOpnd);
 INLINE_SIM_MAIN (void) do_syscall (SIM_DESC sd);
-void program_interrupt (SIM_DESC sd, sim_cpu *cpu, sim_cia cia, SIM_SIGNAL sig);
+void program_interrupt (SIM_DESC sd, sim_cpu *cpu, sim_cia cia, SIM_SIGNAL sig)
+  ATTRIBUTE_NORETURN;
 
 void mn10300_cpu_exception_trigger(SIM_DESC sd, sim_cpu* cpu, address_word pc);
 void mn10300_cpu_exception_suspend(SIM_DESC sd, sim_cpu* cpu, int exception);
diff --git a/sim/mn10300/sim-main.h b/sim/mn10300/sim-main.h
index d08b13dc5315..b0f0d12c6512 100644
--- a/sim/mn10300/sim-main.h
+++ b/sim/mn10300/sim-main.h
@@ -48,6 +48,6 @@ mn10300_core_signal ((SD), (CPU), (CIA), (MAP), (NR_BYTES), (ADDR), (TRANSFER),
 #include "mn10300-sim.h"
 #endif
 
-extern SIM_CORE_SIGNAL_FN mn10300_core_signal;
+extern SIM_CORE_SIGNAL_FN mn10300_core_signal ATTRIBUTE_NORETURN;
 
 #endif
