Patchwork [RFA/v5] (Ada) New command to stop at start of exception handler.

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Submitter Xavier Roirand
Date Jan. 2, 2018, 3:48 p.m.
Message ID <1514908089-29151-1-git-send-email-roirand@adacore.com>
Download mbox | patch
Permalink /patch/25182/
State New
Headers show

Comments

Xavier Roirand - Jan. 2, 2018, 3:48 p.m.
When using gdb for debugging Ada source code, there are several catchpoint
types you can define in order to stop upon certain conditions.  Let's
use this small example:

procedure Foo is
begin
   begin
      raise Constraint_Error;
   exception
      when Program_Error =>
         null;
      when Constraint_Error =>
         null;
      when others =>
         null;
   end;
end Foo;

One can stop when the exception is being raised by using the exception
catchpoint like below:

(gdb) catch exception
Catchpoint 1: all Ada exceptions
(gdb)

In that case, when running Foo, gdb will stop at the line where the exception
was raised:

   begin
>>>   raise Constraint_Error;
   exception

This patch introduces new type of catchpoint, when the user wants to stop
at the location of the exception handling.
Imagine we want to stop on any exception handled by the program, we can do:

(gdb) catch handlers
Catchpoint 1: all Ada exceptions handlers
(gdb) r
Starting program: /tmp/foo

By doing so, when running Foo, gdb will stop here:

Catchpoint 1, exception at 0x000000000040255a in foo () at foo.adb:25
25          when Constraint_Error =>
(gdb)

It is also possible to stop when the Constraint_Error exception is being
handled in this program.  With this patch, we can use:

(gdb) catch handlers Constraint_Error
Catchpoint 1: `Constraint_Error' Ada exception handlers
(gdb)

Like for other catchpoint, you can set a condition when adding a catchpoint
on exception handlers.
Here the handlers catchpoint checks Global_Var:

(gdb) catch handlers Constraint_Error if Global_Var /= 0

gdb/ChangeLog:

        * ada-lang.h (ada_exception_catchpoint_kind) <ada_catch_handlers>:
        Add field.
        * ada-lang.c (struct exception_support_info) <catch_handlers_sym>:
        Add field.
        (default_exception_support_info) <catch_handlers_sym>: Add field.
        (exception_support_info_fallback) <catch_handlers_sym>: Add field.
        (ada_exception_name_addr_1): Add "catch handlers" handling.
        (ada_exception_catchpoint_cond_string) <ex>: New parameter.
        Update all callers.
        (create_excep_cond_exprs) <ex>: Add parameter.
        (re_set_exception): Update create_excep_cond_exprs call.
        (print_it_exception, print_one_exception, print_mention_exception)
        (print_recreate_exception): Add "catch handler" handling.
        (allocate_location_catch_handlers, re_set_catch_handlers)
        (check_status_catch_handlers, print_it_catch_handlers)
        (print_one_catch_handlers, print_mention_catch_handlers)
        (print_recreate_catch_handlers): New function.
        (catch_handlers_breakpoint_ops): New variable.
        (catch_ada_exception_command_split) <is_catch_handlers_cmd>:
        Add parameter.  Add "catch handler" handling.
        (ada_exception_sym_name, ada_exception_breakpoint_ops):
        Add "catch handler" handling.
        (ada_exception_catchpoint_cond_string): Add "catch handler"
        handling.
        (create_ada_exception_catchpoint): Update create_excep_cond_exprs
        call.
        (catch_ada_handlers_command): New function.
        (initialize_ada_catchpoint_ops): Initialize "catch handlers"
        operations structure.
        (_initialize_ada_language): Add "catch handlers" command entry.
        * NEWS: Document "catch handlers" feature.

gdb/doc/ChangeLog:

        * gdb.texinfo (Set Catchpoints): Add documentation for new
        "catch handlers" action.

gdb/testsuite/ChangeLog:

        gdb.ada/excep_handle.exp: New testcase.
        gdb.ada/excep_handle/foo.adb: New file.
        gdb.ada/excep_handle/pck.ads: New file.

Tested on x86_64-linux.
---
 gdb/NEWS                                   |   3 +
 gdb/ada-lang.c                             | 197 +++++++++++++++++++++++++++--
 gdb/ada-lang.h                             |   3 +-
 gdb/doc/gdb.texinfo                        |  20 +++
 gdb/testsuite/gdb.ada/excep_handle.exp     | 171 +++++++++++++++++++++++++
 gdb/testsuite/gdb.ada/excep_handle/foo.adb | 103 +++++++++++++++
 gdb/testsuite/gdb.ada/excep_handle/pck.ads |  19 +++
 7 files changed, 502 insertions(+), 14 deletions(-)
 create mode 100644 gdb/testsuite/gdb.ada/excep_handle.exp
 create mode 100644 gdb/testsuite/gdb.ada/excep_handle/foo.adb
 create mode 100644 gdb/testsuite/gdb.ada/excep_handle/pck.ads
Joel Brobecker - Jan. 3, 2018, 3:23 a.m.
Hi Xavier,

> gdb/ChangeLog:
> 
>         * ada-lang.h (ada_exception_catchpoint_kind) <ada_catch_handlers>:
>         Add field.
>         * ada-lang.c (struct exception_support_info) <catch_handlers_sym>:
>         Add field.
>         (default_exception_support_info) <catch_handlers_sym>: Add field.
>         (exception_support_info_fallback) <catch_handlers_sym>: Add field.
>         (ada_exception_name_addr_1): Add "catch handlers" handling.
>         (ada_exception_catchpoint_cond_string) <ex>: New parameter.
>         Update all callers.
>         (create_excep_cond_exprs) <ex>: Add parameter.
>         (re_set_exception): Update create_excep_cond_exprs call.
>         (print_it_exception, print_one_exception, print_mention_exception)
>         (print_recreate_exception): Add "catch handler" handling.
>         (allocate_location_catch_handlers, re_set_catch_handlers)
>         (check_status_catch_handlers, print_it_catch_handlers)
>         (print_one_catch_handlers, print_mention_catch_handlers)
>         (print_recreate_catch_handlers): New function.
>         (catch_handlers_breakpoint_ops): New variable.
>         (catch_ada_exception_command_split) <is_catch_handlers_cmd>:
>         Add parameter.  Add "catch handler" handling.
>         (ada_exception_sym_name, ada_exception_breakpoint_ops):
>         Add "catch handler" handling.
>         (ada_exception_catchpoint_cond_string): Add "catch handler"
>         handling.
>         (create_ada_exception_catchpoint): Update create_excep_cond_exprs
>         call.
>         (catch_ada_handlers_command): New function.
>         (initialize_ada_catchpoint_ops): Initialize "catch handlers"
>         operations structure.
>         (_initialize_ada_language): Add "catch handlers" command entry.
>         * NEWS: Document "catch handlers" feature.
> 
> gdb/doc/ChangeLog:
> 
>         * gdb.texinfo (Set Catchpoints): Add documentation for new
>         "catch handlers" action.
> 
> gdb/testsuite/ChangeLog:
> 
>         gdb.ada/excep_handle.exp: New testcase.
>         gdb.ada/excep_handle/foo.adb: New file.
>         gdb.ada/excep_handle/pck.ads: New file.
> 
> Tested on x86_64-linux.

Looks good. You can go ahead and push. Just remember to
actually add the 3 ChangeLog entries before doing so! ;-)
Xavier Roirand - Jan. 3, 2018, 1:59 p.m.
Thanks. Pushed to master.

https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=9f757bf7fcb8834ead780e0c4a76d6029b1402c2

Le 1/3/18 à 4:23 AM, Joel Brobecker a écrit :
> Hi Xavier,
> 
>> gdb/ChangeLog:
>>
>>          * ada-lang.h (ada_exception_catchpoint_kind) <ada_catch_handlers>:
>>          Add field.
>>          * ada-lang.c (struct exception_support_info) <catch_handlers_sym>:
>>          Add field.
>>          (default_exception_support_info) <catch_handlers_sym>: Add field.
>>          (exception_support_info_fallback) <catch_handlers_sym>: Add field.
>>          (ada_exception_name_addr_1): Add "catch handlers" handling.
>>          (ada_exception_catchpoint_cond_string) <ex>: New parameter.
>>          Update all callers.
>>          (create_excep_cond_exprs) <ex>: Add parameter.
>>          (re_set_exception): Update create_excep_cond_exprs call.
>>          (print_it_exception, print_one_exception, print_mention_exception)
>>          (print_recreate_exception): Add "catch handler" handling.
>>          (allocate_location_catch_handlers, re_set_catch_handlers)
>>          (check_status_catch_handlers, print_it_catch_handlers)
>>          (print_one_catch_handlers, print_mention_catch_handlers)
>>          (print_recreate_catch_handlers): New function.
>>          (catch_handlers_breakpoint_ops): New variable.
>>          (catch_ada_exception_command_split) <is_catch_handlers_cmd>:
>>          Add parameter.  Add "catch handler" handling.
>>          (ada_exception_sym_name, ada_exception_breakpoint_ops):
>>          Add "catch handler" handling.
>>          (ada_exception_catchpoint_cond_string): Add "catch handler"
>>          handling.
>>          (create_ada_exception_catchpoint): Update create_excep_cond_exprs
>>          call.
>>          (catch_ada_handlers_command): New function.
>>          (initialize_ada_catchpoint_ops): Initialize "catch handlers"
>>          operations structure.
>>          (_initialize_ada_language): Add "catch handlers" command entry.
>>          * NEWS: Document "catch handlers" feature.
>>
>> gdb/doc/ChangeLog:
>>
>>          * gdb.texinfo (Set Catchpoints): Add documentation for new
>>          "catch handlers" action.
>>
>> gdb/testsuite/ChangeLog:
>>
>>          gdb.ada/excep_handle.exp: New testcase.
>>          gdb.ada/excep_handle/foo.adb: New file.
>>          gdb.ada/excep_handle/pck.ads: New file.
>>
>> Tested on x86_64-linux.
> 
> Looks good. You can go ahead and push. Just remember to
> actually add the 3 ChangeLog entries before doing so! ;-)
>

Patch

diff --git a/gdb/NEWS b/gdb/NEWS
index 44f481d..658d93a 100644
--- a/gdb/NEWS
+++ b/gdb/NEWS
@@ -665,6 +665,9 @@  show max-value-size
 * Support for reading/writing memory and extracting values on architectures
   whose memory is addressable in units of any integral multiple of 8 bits.
 
+catch handlers
+  Allows to break when an Ada exception is handled.
+
 * New remote packets
 
 exec stop reason
diff --git a/gdb/ada-lang.c b/gdb/ada-lang.c
index dad2b17..940c7ba 100644
--- a/gdb/ada-lang.c
+++ b/gdb/ada-lang.c
@@ -12021,6 +12021,10 @@  struct exception_support_info
       a catchpoint on failed assertions.  */
    const char *catch_assert_sym;
 
+   /* The name of the symbol to break on in order to insert
+      a catchpoint on exception handling.  */
+   const char *catch_handlers_sym;
+
    /* Assuming that the inferior just triggered an unhandled exception
       catchpoint, this function is responsible for returning the address
       in inferior memory where the name of that exception is stored.
@@ -12040,6 +12044,7 @@  static const struct exception_support_info default_exception_support_info =
   "__gnat_debug_raise_exception", /* catch_exception_sym */
   "__gnat_unhandled_exception", /* catch_exception_unhandled_sym */
   "__gnat_debug_raise_assert_failure", /* catch_assert_sym */
+  "__gnat_begin_handler", /* catch_handlers_sym */
   ada_unhandled_exception_name_addr
 };
 
@@ -12052,6 +12057,7 @@  static const struct exception_support_info exception_support_info_fallback =
   "__gnat_raise_nodefer_with_msg", /* catch_exception_sym */
   "__gnat_unhandled_exception", /* catch_exception_unhandled_sym */
   "system__assertions__raise_assert_failure",  /* catch_assert_sym */
+  "__gnat_begin_handler", /* catch_handlers_sym */
   ada_unhandled_exception_name_addr_from_raise
 };
 
@@ -12320,7 +12326,12 @@  ada_exception_name_addr_1 (enum ada_exception_catchpoint_kind ex,
       case ada_catch_exception_unhandled:
         return data->exception_info->unhandled_exception_name_addr ();
         break;
-      
+
+      case ada_catch_handlers:
+        return 0;  /* The runtimes does not provide access to the exception
+		      name.  */
+        break;
+
       case ada_catch_assert:
         return 0;  /* Exception name is not relevant in this case.  */
         break;
@@ -12426,7 +12437,9 @@  ada_exception_name_addr (enum ada_exception_catchpoint_kind ex,
   return result;
 }
 
-static char *ada_exception_catchpoint_cond_string (const char *excep_string);
+static char *ada_exception_catchpoint_cond_string
+  (const char *excep_string,
+   enum ada_exception_catchpoint_kind ex);
 
 /* Ada catchpoints.
 
@@ -12489,7 +12502,8 @@  struct ada_catchpoint : public breakpoint
    catchpoint's locations, and store them for later evaluation.  */
 
 static void
-create_excep_cond_exprs (struct ada_catchpoint *c)
+create_excep_cond_exprs (struct ada_catchpoint *c,
+                         enum ada_exception_catchpoint_kind ex)
 {
   struct cleanup *old_chain;
   struct bp_location *bl;
@@ -12505,7 +12519,7 @@  create_excep_cond_exprs (struct ada_catchpoint *c)
 
   /* Compute the condition expression in text form, from the specific
      expection we want to catch.  */
-  cond_string = ada_exception_catchpoint_cond_string (c->excep_string);
+  cond_string = ada_exception_catchpoint_cond_string (c->excep_string, ex);
   old_chain = make_cleanup (xfree, cond_string);
 
   /* Iterate over all the catchpoint's locations, and parse an
@@ -12573,7 +12587,7 @@  re_set_exception (enum ada_exception_catchpoint_kind ex, struct breakpoint *b)
 
   /* Reparse the exception conditional expressions.  One for each
      location.  */
-  create_excep_cond_exprs (c);
+  create_excep_cond_exprs (c, ex);
 }
 
 /* Returns true if we should stop for this breakpoint hit.  If the
@@ -12662,6 +12676,7 @@  print_it_exception (enum ada_exception_catchpoint_kind ex, bpstat bs)
     {
       case ada_catch_exception:
       case ada_catch_exception_unhandled:
+      case ada_catch_handlers:
 	{
 	  const CORE_ADDR addr = ada_exception_name_addr (ex, b);
 	  char exception_name[256];
@@ -12759,6 +12774,17 @@  print_one_exception (enum ada_exception_catchpoint_kind ex,
         uiout->field_string ("what", "unhandled Ada exceptions");
         break;
       
+      case ada_catch_handlers:
+        if (c->excep_string != NULL)
+          {
+	    uiout->field_fmt ("what",
+			      _("`%s' Ada exception handlers"),
+			      c->excep_string);
+          }
+        else
+	  uiout->field_string ("what", "all Ada exceptions handlers");
+        break;
+
       case ada_catch_assert:
         uiout->field_string ("what", "failed Ada assertions");
         break;
@@ -12802,7 +12828,19 @@  print_mention_exception (enum ada_exception_catchpoint_kind ex,
       case ada_catch_exception_unhandled:
         uiout->text (_("unhandled Ada exceptions"));
         break;
-      
+
+      case ada_catch_handlers:
+        if (c->excep_string != NULL)
+	  {
+	    std::string info
+	      = string_printf (_("`%s' Ada exception handlers"),
+			       c->excep_string);
+	    uiout->text (info.c_str ());
+	  }
+        else
+          uiout->text (_("all Ada exceptions handlers"));
+        break;
+
       case ada_catch_assert:
         uiout->text (_("failed Ada assertions"));
         break;
@@ -12834,6 +12872,10 @@  print_recreate_exception (enum ada_exception_catchpoint_kind ex,
 	fprintf_filtered (fp, "catch exception unhandled");
 	break;
 
+      case ada_catch_handlers:
+	fprintf_filtered (fp, "catch handlers");
+	break;
+
       case ada_catch_assert:
 	fprintf_filtered (fp, "catch assert");
 	break;
@@ -12984,6 +13026,54 @@  print_recreate_catch_assert (struct breakpoint *b, struct ui_file *fp)
 
 static struct breakpoint_ops catch_assert_breakpoint_ops;
 
+/* Virtual table for "catch handlers" breakpoints.  */
+
+static struct bp_location *
+allocate_location_catch_handlers (struct breakpoint *self)
+{
+  return allocate_location_exception (ada_catch_handlers, self);
+}
+
+static void
+re_set_catch_handlers (struct breakpoint *b)
+{
+  re_set_exception (ada_catch_handlers, b);
+}
+
+static void
+check_status_catch_handlers (bpstat bs)
+{
+  check_status_exception (ada_catch_handlers, bs);
+}
+
+static enum print_stop_action
+print_it_catch_handlers (bpstat bs)
+{
+  return print_it_exception (ada_catch_handlers, bs);
+}
+
+static void
+print_one_catch_handlers (struct breakpoint *b,
+			  struct bp_location **last_loc)
+{
+  print_one_exception (ada_catch_handlers, b, last_loc);
+}
+
+static void
+print_mention_catch_handlers (struct breakpoint *b)
+{
+  print_mention_exception (ada_catch_handlers, b);
+}
+
+static void
+print_recreate_catch_handlers (struct breakpoint *b,
+			       struct ui_file *fp)
+{
+  print_recreate_exception (ada_catch_handlers, b, fp);
+}
+
+static struct breakpoint_ops catch_handlers_breakpoint_ops;
+
 /* Return a newly allocated copy of the first space-separated token
    in ARGSP, and then adjust ARGSP to point immediately after that
    token.
@@ -13022,12 +13112,15 @@  ada_get_next_arg (const char **argsp)
    Set EX to the appropriate catchpoint type.
    Set EXCEP_STRING to the name of the specific exception if
    specified by the user.
+   IS_CATCH_HANDLERS_CMD: True if the arguments are for a
+   "catch handlers" command.  False otherwise.
    If a condition is found at the end of the arguments, the condition
    expression is stored in COND_STRING (memory must be deallocated
    after use).  Otherwise COND_STRING is set to NULL.  */
 
 static void
 catch_ada_exception_command_split (const char *args,
+				   bool is_catch_handlers_cmd,
                                    enum ada_exception_catchpoint_kind *ex,
 				   char **excep_string,
 				   char **cond_string)
@@ -13073,7 +13166,13 @@  catch_ada_exception_command_split (const char *args,
 
   discard_cleanups (old_chain);
 
-  if (exception_name == NULL)
+  if (is_catch_handlers_cmd)
+    {
+      /* Catch handling of exceptions.  */
+      *ex = ada_catch_handlers;
+      *excep_string = exception_name;
+    }
+  else if (exception_name == NULL)
     {
       /* Catch all exceptions.  */
       *ex = ada_catch_exception;
@@ -13115,6 +13214,9 @@  ada_exception_sym_name (enum ada_exception_catchpoint_kind ex)
       case ada_catch_assert:
         return (data->exception_info->catch_assert_sym);
         break;
+      case ada_catch_handlers:
+        return (data->exception_info->catch_handlers_sym);
+        break;
       default:
         internal_error (__FILE__, __LINE__,
                         _("unexpected catchpoint kind (%d)"), ex);
@@ -13138,6 +13240,9 @@  ada_exception_breakpoint_ops (enum ada_exception_catchpoint_kind ex)
       case ada_catch_assert:
         return (&catch_assert_breakpoint_ops);
         break;
+      case ada_catch_handlers:
+        return (&catch_handlers_breakpoint_ops);
+        break;
       default:
         internal_error (__FILE__, __LINE__,
                         _("unexpected catchpoint kind (%d)"), ex);
@@ -13148,14 +13253,29 @@  ada_exception_breakpoint_ops (enum ada_exception_catchpoint_kind ex)
    being raised with the exception that the user wants to catch.  This
    assumes that this condition is used when the inferior just triggered
    an exception catchpoint.
+   EX: the type of catchpoints used for catching Ada exceptions.
    
    The string returned is a newly allocated string that needs to be
    deallocated later.  */
 
 static char *
-ada_exception_catchpoint_cond_string (const char *excep_string)
+ada_exception_catchpoint_cond_string (const char *excep_string,
+                                      enum ada_exception_catchpoint_kind ex)
 {
   int i;
+  bool is_standard_exc = false;
+  const char *actual_exc_expr;
+  char *ref_exc_expr;
+
+  if (ex == ada_catch_handlers)
+    {
+      /* For exception handlers catchpoints, the condition string does
+         not use the same parameter as for the other exceptions.  */
+      actual_exc_expr = ("long_integer (GNAT_GCC_exception_Access"
+			 "(gcc_exception).all.occurrence.id)");
+    }
+  else
+    actual_exc_expr = "long_integer (e)";
 
   /* The standard exceptions are a special case.  They are defined in
      runtime units that have been compiled without debugging info; if
@@ -13180,11 +13300,19 @@  ada_exception_catchpoint_cond_string (const char *excep_string)
     {
       if (strcmp (standard_exc [i], excep_string) == 0)
 	{
-          return xstrprintf ("long_integer (e) = long_integer (&standard.%s)",
-                             excep_string);
+	  is_standard_exc = true;
+	  break;
 	}
     }
-  return xstrprintf ("long_integer (e) = long_integer (&%s)", excep_string);
+
+  if (is_standard_exc)
+    ref_exc_expr = xstrprintf ("long_integer (&standard.%s)", excep_string);
+  else
+    ref_exc_expr = xstrprintf ("long_integer (&%s)", excep_string);
+
+  char *result =  xstrprintf ("%s = %s", actual_exc_expr, ref_exc_expr);
+  xfree (ref_exc_expr);
+  return result;
 }
 
 /* Return the symtab_and_line that should be used to insert an exception
@@ -13267,7 +13395,7 @@  create_ada_exception_catchpoint (struct gdbarch *gdbarch,
   init_ada_exception_breakpoint (c.get (), gdbarch, sal, addr_string,
 				 ops, tempflag, disabled, from_tty);
   c->excep_string = excep_string;
-  create_excep_cond_exprs (c.get ());
+  create_excep_cond_exprs (c.get (), ex_kind);
   if (cond_string != NULL)
     set_breakpoint_condition (c.get (), cond_string, from_tty);
   install_breakpoint (0, std::move (c), 1);
@@ -13290,7 +13418,32 @@  catch_ada_exception_command (const char *arg_entry, int from_tty,
 
   if (!arg)
     arg = "";
-  catch_ada_exception_command_split (arg, &ex_kind, &excep_string,
+  catch_ada_exception_command_split (arg, false, &ex_kind, &excep_string,
+				     &cond_string);
+  create_ada_exception_catchpoint (gdbarch, ex_kind,
+				   excep_string, cond_string,
+				   tempflag, 1 /* enabled */,
+				   from_tty);
+}
+
+/* Implement the "catch handlers" command.  */
+
+static void
+catch_ada_handlers_command (const char *arg_entry, int from_tty,
+			    struct cmd_list_element *command)
+{
+  const char *arg = arg_entry;
+  struct gdbarch *gdbarch = get_current_arch ();
+  int tempflag;
+  enum ada_exception_catchpoint_kind ex_kind;
+  char *excep_string = NULL;
+  char *cond_string = NULL;
+
+  tempflag = get_cmd_context (command) == CATCH_TEMPORARY;
+
+  if (!arg)
+    arg = "";
+  catch_ada_exception_command_split (arg, true, &ex_kind, &excep_string,
 				     &cond_string);
   create_ada_exception_catchpoint (gdbarch, ex_kind,
 				   excep_string, cond_string,
@@ -14405,6 +14558,16 @@  initialize_ada_catchpoint_ops (void)
   ops->print_one = print_one_catch_assert;
   ops->print_mention = print_mention_catch_assert;
   ops->print_recreate = print_recreate_catch_assert;
+
+  ops = &catch_handlers_breakpoint_ops;
+  *ops = bkpt_breakpoint_ops;
+  ops->allocate_location = allocate_location_catch_handlers;
+  ops->re_set = re_set_catch_handlers;
+  ops->check_status = check_status_catch_handlers;
+  ops->print_it = print_it_catch_handlers;
+  ops->print_one = print_one_catch_handlers;
+  ops->print_mention = print_mention_catch_handlers;
+  ops->print_recreate = print_recreate_catch_handlers;
 }
 
 /* This module's 'new_objfile' observer.  */
@@ -14465,6 +14628,14 @@  With an argument, catch only exceptions with the given name."),
                      NULL,
 		     CATCH_PERMANENT,
 		     CATCH_TEMPORARY);
+
+  add_catch_command ("handlers", _("\
+Catch Ada exceptions, when handled.\n\
+With an argument, catch only exceptions with the given name."),
+		     catch_ada_handlers_command,
+                     NULL,
+		     CATCH_PERMANENT,
+		     CATCH_TEMPORARY);
   add_catch_command ("assert", _("\
 Catch failed Ada assertions, when raised.\n\
 With an argument, catch only exceptions with the given name."),
diff --git a/gdb/ada-lang.h b/gdb/ada-lang.h
index 0530e9a..787bc2f 100644
--- a/gdb/ada-lang.h
+++ b/gdb/ada-lang.h
@@ -108,7 +108,8 @@  enum ada_exception_catchpoint_kind
 {
   ada_catch_exception,
   ada_catch_exception_unhandled,
-  ada_catch_assert
+  ada_catch_assert,
+  ada_catch_handlers
 };
 
 /* Ada task structures.  */
diff --git a/gdb/doc/gdb.texinfo b/gdb/doc/gdb.texinfo
index 60ed80c..594456b 100644
--- a/gdb/doc/gdb.texinfo
+++ b/gdb/doc/gdb.texinfo
@@ -4458,6 +4458,26 @@  called @code{Constraint_Error} is defined in package @code{Pck}, then
 the command to use to catch such exceptions is @kbd{catch exception
 Pck.Constraint_Error}.
 
+@item handlers
+@kindex catch handlers
+@cindex Ada exception handlers catching
+@cindex catch Ada exceptions when handled
+An Ada exception being handled.  If an exception name is
+specified at the end of the command
+ (eg @kbd{catch handlers Program_Error}), the debugger will stop
+only when this specific exception is handled.
+Otherwise, the debugger stops execution when any Ada exception is handled.
+
+When inserting a handlers catchpoint on a user-defined
+exception whose name is identical to one of the exceptions
+defined by the language, the fully qualified name must be used
+as the exception name.  Otherwise, @value{GDBN} will assume that it
+should stop on the pre-defined exception rather than the
+user-defined one.  For instance, assuming an exception called
+ @code{Constraint_Error} is defined in package @code{Pck}, then the
+command to use to catch such exceptions handling is
+@kbd{catch handlers Pck.Constraint_Error}.
+
 @item exception unhandled
 @kindex catch exception unhandled
 An exception that was raised but is not handled by the program.
diff --git a/gdb/testsuite/gdb.ada/excep_handle.exp b/gdb/testsuite/gdb.ada/excep_handle.exp
new file mode 100644
index 0000000..c693fd3
--- /dev/null
+++ b/gdb/testsuite/gdb.ada/excep_handle.exp
@@ -0,0 +1,171 @@ 
+# Copyright 2018 Free Software Foundation, Inc.
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+load_lib "ada.exp"
+
+standard_ada_testfile foo
+
+if {[gdb_compile_ada "${srcfile}" "${binfile}" executable [list debug additional_flags=-gnata ]] != "" } {
+  return -1
+}
+
+clean_restart ${testfile}
+
+# Some global variables used to simplify the maintenance of some of
+# the regular expressions below.
+set eol "\[\r\n\]+"
+set sp "\[ \t\]*"
+
+set when "when"
+set catchpoint_constraint_error_msg \
+  "Catchpoint $decimal, exception at $hex in foo \\\(\\\).*at .*foo.adb:$decimal$eol$decimal$sp$when Constraint_Error =>"
+
+set catchpoint_program_error_msg \
+  "Catchpoint $decimal, exception at $hex in foo \\\(\\\).*at .*foo.adb:$decimal$eol$decimal$sp$when Program_Error =>"
+
+set catchpoint_storage_error_msg \
+  "Catchpoint $decimal, exception at $hex in foo \\\(\\\).*at .*foo.adb:$decimal$eol$decimal$sp$when Storage_Error =>"
+
+############################################
+# Check that runtime supports catchpoint.  #
+############################################
+
+if ![runto_main] then {
+   fail "Cannot run to main, testcase aborted"
+   return 0
+}
+
+set msg "insert catchpoint on all Ada exceptions handlers"
+gdb_test_multiple "catch handlers" $msg {
+    -re "Catchpoint $decimal: all Ada exceptions handlers$eol$gdb_prompt $" {
+	pass $msg
+    }
+    -re "Your Ada runtime appears to be missing some debugging information.*$eol$gdb_prompt $" {
+	# If the runtime was not built with enough debug information,
+	# or if it was stripped, we can not test exception handlers
+	# catchpoints.
+	unsupported $msg
+	return -1
+    }
+}
+
+############################################
+# 1. Try catching all exceptions handlers. #
+############################################
+
+# Continue.  The program should stop at first exception handling.
+
+gdb_test "continue" \
+         "Continuing\.$eol$catchpoint_constraint_error_msg$eol.*" \
+         "continuing to first Constraint_Error exception handlers"
+
+# Resume the program's exception.
+#
+# The program will first go through a block of code which has an
+# exception handler, but since no exception is raised, we should
+# not stop there.  Instead, we expect to stop in the handler of
+# the next exception being raised.
+
+gdb_test "continue" \
+         "Continuing\.$eol$catchpoint_storage_error_msg$eol.*" \
+         "continuing and stopping in Storage_Error exception handlers"
+
+gdb_test_no_output "delete 2" \
+                   "delete catchpoint on all Ada exceptions handlers"
+
+##################################################
+# 2. Try catching some named exception handlers. #
+##################################################
+
+# Insert a catchpoint on Program_Error Ada exception handlers.
+
+gdb_test "catch handlers Program_Error" \
+         "Catchpoint $decimal: `Program_Error' Ada exception handlers" \
+         "insert catchpoint on Program_Error Ada exception handlers"
+
+# Continue, we should not stop at ABORT_SIGNAL but at Program_Error one.
+
+gdb_test "continue" \
+         "Continuing\.$eol$catchpoint_program_error_msg$eol.*" \
+         "continuing without stopping to Program_Error exception handlers"
+
+gdb_test_no_output \
+    "delete 3" \
+    "delete catchpoint on all Program_Error Ada exception handlers"
+
+# Insert a catchpoint on Storage_Error Ada exception handlers.
+
+gdb_test "catch handlers Storage_Error" \
+         "Catchpoint $decimal: `Storage_Error' Ada exception handlers" \
+         "insert catchpoint on Storage_Error Ada exception handlers"
+
+# Continue, we should stop at Storage_Error handlers.
+
+gdb_test "continue" \
+         "Continuing\.$eol$catchpoint_storage_error_msg$eol.*" \
+         "continuing without stopping to Storage_Error exception handlers"
+
+gdb_test_no_output \
+    "delete 4" \
+    "delete catchpoint on all Storage_Error Ada exception handlers"
+
+########################################################################
+# 3. Try catching with condition and without named exception handlers. #
+########################################################################
+
+# Insert a catchpoint on all Ada exceptions handlers with condition.
+
+gdb_test "catch handlers if Global_Var = 2" \
+         "Catchpoint $decimal: all Ada exceptions handlers" \
+         "insert catchpoint on all Ada exception handlers with condition"
+
+# Check that condition is stored and properly displayed.
+
+gdb_test "info breakpoint" "stop only if Global_Var = 2" \
+         "Check catch handlers with condition"
+
+# Continue, we should not stop at ABORT_SIGNAL but at Program_Error one.
+
+gdb_test "continue" \
+         "Continuing\.$eol$catchpoint_constraint_error_msg$eol.*" \
+         "continuing to second Constraint_Error exception handlers"
+
+gdb_test_no_output \
+    "delete 5" \
+    "delete catchpoint on all all Ada exceptions handlers with condition"
+
+################################################################
+# 4. Try catching with condition and named exception handlers. #
+################################################################
+
+# Insert a catchpoint on Program_Error Ada exception handlers with
+# condition.
+
+gdb_test "catch handlers Program_Error if Global_Var = 4" \
+    "Catchpoint $decimal: `Program_Error' Ada exception handlers" \
+    "insert catchpoint on Program_Error Ada exception handlers with condition"
+
+# Continue, we should not stop at first Program_Error handlers but at
+# the second one.
+
+gdb_test "continue" \
+         "Continuing\.$eol$catchpoint_program_error_msg$eol.*" \
+         "continuing to Program_Error exception handlers"
+
+# Continue, the program should exit properly.
+
+gdb_test "continue" \
+         "Continuing\..*$inferior_exited_re.*" \
+         "continuing to program completion"
diff --git a/gdb/testsuite/gdb.ada/excep_handle/foo.adb b/gdb/testsuite/gdb.ada/excep_handle/foo.adb
new file mode 100644
index 0000000..93c6843
--- /dev/null
+++ b/gdb/testsuite/gdb.ada/excep_handle/foo.adb
@@ -0,0 +1,103 @@ 
+--  Copyright 2018 Free Software Foundation, Inc.
+--
+--  This program is free software; you can redistribute it and/or modify
+--  it under the terms of the GNU General Public License as published by
+--  the Free Software Foundation; either version 3 of the License, or
+--  (at your option) any later version.
+--
+--  This program is distributed in the hope that it will be useful,
+--  but WITHOUT ANY WARRANTY; without even the implied warranty of
+--  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+--  GNU General Public License for more details.
+--
+--  You should have received a copy of the GNU General Public License
+--  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+with Pck; use Pck;
+
+procedure Foo is
+begin
+
+   -- Part 1 of the testcase
+
+   begin
+      raise Constraint_Error;
+   exception
+      when Constraint_Error =>
+         null;
+   end;
+
+   begin
+      null;
+   exception
+      when others =>
+         null;
+   end;
+
+   begin
+      raise Storage_Error;
+   exception
+      when Storage_Error =>
+         null;
+   end;
+
+   -- Part 2 of the testcase
+
+   begin
+      raise ABORT_SIGNAL;
+   exception
+      when others =>
+         null;
+   end;
+
+   begin
+      raise Program_Error;
+   exception
+      when Program_Error =>
+         null;
+   end;
+
+   begin
+      raise Storage_Error;
+   exception
+      when Storage_Error =>
+         null;
+   end;
+
+  -- Part 3 of the testcase
+
+   begin
+      Global_Var := Global_Var + 1;
+      raise ABORT_SIGNAL;
+   exception
+      when others =>
+         null;
+   end;
+
+   begin
+      Global_Var := Global_Var + 1;
+      raise Constraint_Error;
+   exception
+      when Constraint_Error =>
+         null;
+   end;
+
+   -- Part 4 of the testcase
+
+   begin
+      Global_Var := Global_Var + 1;
+      raise Program_Error;
+   exception
+      when others =>
+         null;
+   end;
+
+   begin
+      Global_Var := Global_Var + 1;
+      raise Program_Error;
+   exception
+      when Program_Error =>
+         null;
+   end;
+
+end Foo;
diff --git a/gdb/testsuite/gdb.ada/excep_handle/pck.ads b/gdb/testsuite/gdb.ada/excep_handle/pck.ads
new file mode 100644
index 0000000..6a7cf08
--- /dev/null
+++ b/gdb/testsuite/gdb.ada/excep_handle/pck.ads
@@ -0,0 +1,19 @@ 
+--  Copyright 2018 Free Software Foundation, Inc.
+--
+--  This program is free software; you can redistribute it and/or modify
+--  it under the terms of the GNU General Public License as published by
+--  the Free Software Foundation; either version 3 of the License, or
+--  (at your option) any later version.
+--
+--  This program is distributed in the hope that it will be useful,
+--  but WITHOUT ANY WARRANTY; without even the implied warranty of
+--  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+--  GNU General Public License for more details.
+--
+--  You should have received a copy of the GNU General Public License
+--  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+package Pck is
+   Global_Var : Integer := 0;
+   ABORT_SIGNAL : exception;
+end Pck;