PR 48915 Abort handling

From-SVN: r173750

diff --git a/gcc/fortran/ChangeLog b/gcc/fortran/ChangeLog
index 4be4e5db4f4df99cef36c67e5bec11ca295e223b..afc553384adff5236c346065cbc122c45ad7edd5 100644 (file)
--- a/gcc/fortran/ChangeLog
+++ b/gcc/fortran/ChangeLog
@@ -1,3 +1,18 @@
+2011-05-14  Janne Blomqvist  <jb@gcc.gnu.org>
+
+        PR libfortran/48915
+        * gfortran.h (gfc_option_t): Remove flag_dump_core.
+        * gfortran.texi (GFORTRAN_ERROR_DUMPCORE): Remove section.
+        (GFORTRAN_ERROR_BACKTRACE): Document that it's enabled by default.
+        * intrinsic.texi (ABORT): Remove explanation of -fdump-core.
+        * invoke.texi: Remove -fdump-core, document that -fbacktrace is
+        enabled by default.
+        * lang.opt: Remove -fdump-core.
+        * options.c (gfc_init_options): Make backtrace default to enabled,
+        remove dump_core.
+        (gfc_handle_option): Remove OPT_fdump-core.
+        * trans-decl.c: Pass a 0 to preserve ABI.
+
 2011-05-14  Janne Blomqvist  <jb@gcc.gnu.org>
 
         * gfortran.texi: Remove GFORTRAN_USE_STDERR documentation.

diff --git a/gcc/fortran/gfortran.h b/gcc/fortran/gfortran.h
index 92adf72e8af544f87758f7eac97b233f20f53b06..3b4967de63af63163f4568e199105282deef3e4f 100644 (file)
--- a/gcc/fortran/gfortran.h
+++ b/gcc/fortran/gfortran.h
@@ -2212,7 +2212,6 @@ typedef struct
   int flag_backslash;
   int flag_backtrace;
   int flag_allow_leading_underscore;
-  int flag_dump_core;
   int flag_external_blas;
   int blas_matmul_limit;
   int flag_cray_pointer;

diff --git a/gcc/fortran/gfortran.texi b/gcc/fortran/gfortran.texi
index c810fe251d6689021684375c9ab7e6045503bc16..518c998793e4f4e4692d1e04682a614bfd280615 100644 (file)
--- a/gcc/fortran/gfortran.texi
+++ b/gcc/fortran/gfortran.texi
@@ -587,7 +587,6 @@ Malformed environment variables are silently ignored.
 * GFORTRAN_DEFAULT_RECL:: Default record length for new files
 * GFORTRAN_LIST_SEPARATOR::  Separator for list output
 * GFORTRAN_CONVERT_UNIT::  Set endianness for unformatted I/O
-* GFORTRAN_ERROR_DUMPCORE:: Dump core on run-time errors
 * GFORTRAN_ERROR_BACKTRACE:: Show backtrace on run-time errors
 @end menu
 
@@ -745,26 +744,15 @@ environment variable will override the CONVERT specifier in the
 open statement}.  This is to give control over data formats to
 users who do not have the source code of their program available.
 
-@node GFORTRAN_ERROR_DUMPCORE
-@section @env{GFORTRAN_ERROR_DUMPCORE}---Dump core on run-time errors
-
-If the @env{GFORTRAN_ERROR_DUMPCORE} variable is set to
-@samp{y}, @samp{Y} or @samp{1} (only the first letter is relevant)
-then library run-time errors cause core dumps.  To disable the core
-dumps, set the variable to @samp{n}, @samp{N}, @samp{0}.  Default
-is not to core dump unless the @option{-fdump-core} compile option
-was used.
-
 @node GFORTRAN_ERROR_BACKTRACE
 @section @env{GFORTRAN_ERROR_BACKTRACE}---Show backtrace on run-time errors
 
-If the @env{GFORTRAN_ERROR_BACKTRACE} variable is set to
-@samp{y}, @samp{Y} or @samp{1} (only the first letter is relevant)
-then a backtrace is printed when a run-time error occurs.
-To disable the backtracing, set the variable to
-@samp{n}, @samp{N}, @samp{0}.  Default is not to print a backtrace
-unless the @option{-fbacktrace} compile option
-was used.
+If the @env{GFORTRAN_ERROR_BACKTRACE} variable is set to @samp{y},
+@samp{Y} or @samp{1} (only the first letter is relevant) then a
+backtrace is printed when a serious run-time error occurs.  To disable
+the backtracing, set the variable to @samp{n}, @samp{N}, @samp{0}.
+Default is to print a backtrace unless the @option{-fno-backtrace}
+compile option was used.
 
 @c =====================================================================
 @c PART II: LANGUAGE REFERENCE

diff --git a/gcc/fortran/intrinsic.texi b/gcc/fortran/intrinsic.texi
index ebffb1233a3c2270b4d591ec2fcc69b859712902..804b31f8f49d20170a832ea44ef17dede3324ee7 100644 (file)
--- a/gcc/fortran/intrinsic.texi
+++ b/gcc/fortran/intrinsic.texi
@@ -345,10 +345,7 @@ the applicable standard for each intrinsic procedure is noted.
 @table @asis
 @item @emph{Description}:
 @code{ABORT} causes immediate termination of the program.  On operating
-systems that support a core dump, @code{ABORT} will produce a core dump even if
-the option @option{-fno-dump-core} is in effect, which is suitable for debugging
-purposes.
-@c TODO: Check if this (with -fno-dump-core) is correct.
+systems that support a core dump, @code{ABORT} will produce a core dump.
 
 @item @emph{Standard}:
 GNU extension

diff --git a/gcc/fortran/invoke.texi b/gcc/fortran/invoke.texi
index 9f022390b56917665dc50e32a34dfa6f74b1ed5e..f68b18c677663eafdb29fa51b24af2b8b61fb4a1 100644 (file)
--- a/gcc/fortran/invoke.texi
+++ b/gcc/fortran/invoke.texi
@@ -145,7 +145,7 @@ and warnings}.
 @item Debugging Options
 @xref{Debugging Options,,Options for debugging your program or GNU Fortran}.
 @gccoptlist{-fdump-fortran-original  -fdump-fortran-optimized @gol
--ffpe-trap=@var{list}  -fdump-core -fbacktrace -fdump-parse-tree}
+-ffpe-trap=@var{list} -fbacktrace -fdump-parse-tree}
 
 @item Directory Options
 @xref{Directory Options,,Options for directory search}.
@@ -935,22 +935,18 @@ Some of the routines in the Fortran runtime library, like
 @code{ffpe-trap=precision} is used. For this reason, the use of 
 @code{ffpe-trap=precision} is not recommended.
 
-@item -fbacktrace
-@opindex @code{fbacktrace}
+@item -fno-backtrace
+@opindex @code{fno-backtrace}
 @cindex backtrace
 @cindex trace
-Specify that, when a runtime error is encountered or a deadly signal is
-emitted (segmentation fault, illegal instruction, bus error or
-floating-point exception), the Fortran runtime
-library should output a backtrace of the error.  This option
-only has influence for compilation of the Fortran main program.
-
-@item -fdump-core
-@cindex core, dump
-@opindex @code{fdump-core}
-Request that a core-dump file is written to disk when a runtime error
-is encountered on systems that support core dumps. This option is
-only effective for the compilation of the Fortran main program.
+When a serious runtime error is encountered or a deadly signal is
+emitted (segmentation fault, illegal instruction, bus error,
+floating-point exception, and the other POSIX signals that have the
+action @samp{core}), the Fortran runtime library tries to output a
+backtrace of the error. @code{-fno-backtrace} disables the backtrace
+generation. This option only has influence for compilation of the
+Fortran main program.
+
 @end table
 
 @xref{Debugging Options,,Options for Debugging Your Program or GCC,

diff --git a/gcc/fortran/lang.opt b/gcc/fortran/lang.opt
index ce944e3b4cebb41e67515f0a5fe5f4e0d38e7387..a056c5c651ed68faf3bb4cad431d10537bead86d 100644 (file)
--- a/gcc/fortran/lang.opt
+++ b/gcc/fortran/lang.opt
@@ -366,10 +366,6 @@ fdollar-ok
 Fortran
 Allow dollar signs in entity names
 
-fdump-core
-Fortran
-Dump a core file when a runtime error occurs
-
 fdump-fortran-original
 Fortran
 Display the code tree after parsing

diff --git a/gcc/fortran/options.c b/gcc/fortran/options.c
index c67d10916e97ed30e66bf4b26c095753d390a3d5..d4778ba7b1ea67c056945526e335a2188028fecf 100644 (file)
--- a/gcc/fortran/options.c
+++ b/gcc/fortran/options.c
@@ -134,9 +134,8 @@ gfc_init_options (unsigned int decoded_options_count,
   gfc_option.flag_automatic = 1;
   gfc_option.flag_backslash = 0;
   gfc_option.flag_module_private = 0;
-  gfc_option.flag_backtrace = 0;
+  gfc_option.flag_backtrace = 1;
   gfc_option.flag_allow_leading_underscore = 0;
-  gfc_option.flag_dump_core = 0;
   gfc_option.flag_external_blas = 0;
   gfc_option.blas_matmul_limit = 30;
   gfc_option.flag_cray_pointer = 0;
@@ -697,10 +696,6 @@ gfc_handle_option (size_t scode, const char *arg, int value,
       gfc_option.rtcheck |= GFC_RTCHECK_ARRAY_TEMPS;
       break;
       
-    case OPT_fdump_core:
-      gfc_option.flag_dump_core = value;
-      break;
-
     case OPT_fcray_pointer:
       gfc_option.flag_cray_pointer = value;
       break;

diff --git a/gcc/fortran/trans-decl.c b/gcc/fortran/trans-decl.c
index 77e2a594ee26498dc842a27164694f5b491b2302..f0138b0076c82f68ebb7a8fc5d28d95df3eb8b8f 100644 (file)
--- a/gcc/fortran/trans-decl.c
+++ b/gcc/fortran/trans-decl.c
@@ -4636,9 +4636,12 @@ create_main_function (tree fndecl)
                                            gfc_option.allow_std));
     CONSTRUCTOR_APPEND_ELT (v, NULL_TREE,
                             build_int_cst (integer_type_node, pedantic));
+    /* TODO: This is the old -fdump-core option, which is unused but
+       passed due to ABI compatibility; remove when bumping the
+       library ABI.  */
     CONSTRUCTOR_APPEND_ELT (v, NULL_TREE,
                             build_int_cst (integer_type_node,
-                                           gfc_option.flag_dump_core));
+                                           0));
     CONSTRUCTOR_APPEND_ELT (v, NULL_TREE,
                             build_int_cst (integer_type_node,
                                            gfc_option.flag_backtrace));

diff --git a/libgfortran/ChangeLog b/libgfortran/ChangeLog
index 8ed0bb6148fbeac0266a00cd713cffd6f045a008..ada4eae6ef55375f3178eda74e621c3d22a325cc 100644 (file)
--- a/libgfortran/ChangeLog
+++ b/libgfortran/ChangeLog
@@ -1,3 +1,39 @@
+2011-05-14  Janne Blomqvist  <jb@gcc.gnu.org>
+
+        PR libfortran/48915
+        * intrinsics/abort.c (abort): Call sys_abort().
+        * io/unix.c (st_vprintf): Call sys_abort().
+        * libgfortran.h (options_t): Remove dump_core member.
+        (handler): Rename to backtrace_handler.
+        (compile_options_t): Remove dump_core member.
+        (sys_exit): Remove.
+        (sys_abort): New function.
+        * runtime/backtrace.c (show_backtrace): Print a message if
+       backtrace is not available on target, update filter symbol name
+       due to backtrace_handler renaming.
+        * runtime/compile_options.c (backtrace_handler): New
+       implementation based on example in Glibc manual.
+        (set_options): Remove dump_core handling, make signal handler
+       handle more signals.
+        (init_compile_options): Remove dump_core.
+        * runtime/environ.c (variable_table[]): Remove
+       GFORTRAN_ERROR_DUMPCORE element.
+        (show_variables): Update name, call exit().
+        * runtime/error.c (sys_exit): Remove.
+        (sys_abort): New function.
+        (recursion_check): Call sys_abort().
+        (os_error): Call exit().
+        (runtime_error): Likewise.
+        (runtime_error_at): Likewise.
+        (internal_error): Likewise.
+        (generate_error): Likewise.
+        (notify_std): Likewise.
+        * runtime/stop.c (stop_numeric): Call exit().
+        (stop_numeric_f08): Likewise.
+        (stop_string): Likewise.
+        (error_stop_string): Call sys_abort().
+        (error_stop_numeric): Print backtrace, exit with provided code.
+
 2011-05-14  Janne Blomqvist  <jb@gcc.gnu.org>
 
         * io/unix.c (st_vprintf,st_printf): Move to runtime/error.c.

diff --git a/libgfortran/intrinsics/abort.c b/libgfortran/intrinsics/abort.c
index ada4061436522e3a62e208ea2d8c1b3cf998b1b5..543f8fc04c8cc7e5ad6e9bd194f067b166e15452 100644 (file)
--- a/libgfortran/intrinsics/abort.c
+++ b/libgfortran/intrinsics/abort.c
@@ -30,6 +30,5 @@ export_proto_np(PREFIX(abort));
 
 void PREFIX(abort) (void)
 {
-  close_units ();
-  abort ();
+  sys_abort ();
 }

diff --git a/libgfortran/libgfortran.h b/libgfortran/libgfortran.h
index ae86a021ee3fd64f82538856ac217e02f3169044..e77ba10790f77b20088da56b2fc72c5fa5598c5b 100644 (file)
--- a/libgfortran/libgfortran.h
+++ b/libgfortran/libgfortran.h
@@ -509,15 +509,15 @@ typedef struct
   const char *separator;
 
   int all_unbuffered, unbuffered_preconnected, default_recl;
-  int fpe, dump_core, backtrace;
+  int fpe, backtrace;
 }
 options_t;
 
 extern options_t options;
 internal_proto(options);
 
-extern void handler (int);
-internal_proto(handler);
+extern void backtrace_handler (int);
+internal_proto(backtrace_handler);
 
 
 /* Compile-time options that will influence the library.  */
@@ -528,7 +528,6 @@ typedef struct
   int allow_std;
   int pedantic;
   int convert;
-  int dump_core;
   int backtrace;
   int sign_zero;
   size_t record_marker;
@@ -688,8 +687,8 @@ internal_proto(show_backtrace);
 #define GFC_OTOA_BUF_SIZE (GFC_LARGEST_BUF * 3 + 1)
 #define GFC_BTOA_BUF_SIZE (GFC_LARGEST_BUF * 8 + 1)
 
-extern void sys_exit (int) __attribute__ ((noreturn));
-internal_proto(sys_exit);
+extern void sys_abort (void) __attribute__ ((noreturn));
+internal_proto(sys_abort);
 
 extern ssize_t estr_write (const char *);
 internal_proto(estr_write);

diff --git a/libgfortran/runtime/backtrace.c b/libgfortran/runtime/backtrace.c
index aa77025ab749aabad8330019233c4acd90f26429..10917d3e0c22fb5a106a495009cd787768daf550 100644 (file)
--- a/libgfortran/runtime/backtrace.c
+++ b/libgfortran/runtime/backtrace.c
@@ -214,7 +214,7 @@ show_backtrace (void)
            if (strncasecmp (func, "*_gfortran", 10) == 0
                || strncasecmp (func, "_gfortran", 9) == 0
                || strcmp (func, "main") == 0 || strcmp (func, "_start") == 0
-               || strcmp (func, "_gfortrani_handler") == 0)
+               || strcmp (func, "_gfortrani_backtrace_handler") == 0)
              continue;
 
            if (local_strcasestr (str[i], "libgfortran.so") != NULL
@@ -334,5 +334,7 @@ fallback:
   /* Fallback to the glibc backtrace.  */
   estr_write ("\nBacktrace for this error:\n");
   dump_glibc_backtrace (depth, str);
+  return;
 #endif
+  estr_write ("\nBacktrace not yet available on this platform, sorry!\n");
 }

diff --git a/libgfortran/runtime/compile_options.c b/libgfortran/runtime/compile_options.c
index 62c401be6b32e55073eb70cf92899244a7d694d7..dc0da4bcb90e77f7efba01fab6d7a9e37afc5aad 100644 (file)
--- a/libgfortran/runtime/compile_options.c
+++ b/libgfortran/runtime/compile_options.c
@@ -33,49 +33,28 @@ see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
 compile_options_t compile_options;
 
 
+volatile sig_atomic_t fatal_error_in_progress = 0;
+
 /* A signal handler to allow us to output a backtrace.  */
 void
-handler (int signum)
+backtrace_handler (int signum)
 {
-  const char * name = NULL, * desc = NULL;
-
-  switch (signum)
-    {
-#if defined(SIGSEGV)
-      case SIGSEGV:
-       name = "SIGSEGV";
-       desc = "Segmentation fault";
-       break;
-#endif
-
-#if defined(SIGBUS)
-      case SIGBUS:
-       name = "SIGBUS";
-       desc = "Bus error";
-       break;
-#endif
-
-#if defined(SIGILL)
-      case SIGILL:
-       name = "SIGILL";
-       desc = "Illegal instruction";
-       break;
-#endif
-
-#if defined(SIGFPE)
-      case SIGFPE:
-       name = "SIGFPE";
-       desc = "Floating-point exception";
-       break;
-#endif
-    }
-
-  if (name)
-    st_printf ("\nProgram received signal %d (%s): %s.\n", signum, name, desc);
-  else
-    st_printf ("\nProgram received signal %d.\n", signum);
-
-  sys_exit (5);
+  /* Since this handler is established for more than one kind of signal, 
+     it might still get invoked recursively by delivery of some other kind
+     of signal.  Use a static variable to keep track of that. */
+  if (fatal_error_in_progress)
+    raise (signum);
+  fatal_error_in_progress = 1;
+
+  show_backtrace();
+
+  /* Now reraise the signal.  We reactivate the signal's
+     default handling, which is to terminate the process.
+     We could just call exit or abort,
+     but reraising the signal sets the return status
+     from the process correctly. */
+  signal (signum, SIG_DFL);
+  raise (signum);
 }
 
 
@@ -92,8 +71,9 @@ set_options (int num, int options[])
     compile_options.allow_std = options[1];
   if (num >= 3)
     compile_options.pedantic = options[2];
-  if (num >= 4)
-    compile_options.dump_core = options[3];
+  /* options[3] is the removed -fdump-core option. It's place in the
+     options array is retained due to ABI compatibility. Remove when
+     bumping the library ABI.  */
   if (num >= 5)
     compile_options.backtrace = options[4];
   if (num >= 6)
@@ -103,26 +83,53 @@ set_options (int num, int options[])
   if (num >= 8)
     compile_options.range_check = options[7];
 
-  /* If backtrace is required, we set signal handlers on most common
-     signals.  */
-#if defined(HAVE_SIGNAL) && (defined(SIGSEGV) || defined(SIGBUS) \
-                            || defined(SIGILL) || defined(SIGFPE))
+  /* If backtrace is required, we set signal handlers on the POSIX
+     2001 signals with core action.  */
+#if defined(HAVE_SIGNAL) && (defined(SIGQUIT) || defined(SIGILL) \
+                            || defined(SIGABRT) || defined(SIGFPE) \
+                            || defined(SIGSEGV) || defined(SIGBUS) \
+                            || defined(SIGSYS) || defined(SIGTRAP) \
+                            || defined(SIGXCPU) || defined(SIGXFSZ))
   if (compile_options.backtrace)
     {
+#if defined(SIGQUIT)
+      signal (SIGQUIT, backtrace_handler);
+#endif
+
+#if defined(SIGILL)
+      signal (SIGILL, backtrace_handler);
+#endif
+
+#if defined(SIGABRT)
+      signal (SIGABRT, backtrace_handler);
+#endif
+
+#if defined(SIGFPE)
+      signal (SIGFPE, backtrace_handler);
+#endif
+
 #if defined(SIGSEGV)
-      signal (SIGSEGV, handler);
+      signal (SIGSEGV, backtrace_handler);
 #endif
 
 #if defined(SIGBUS)
-      signal (SIGBUS, handler);
+      signal (SIGBUS, backtrace_handler);
 #endif
 
-#if defined(SIGILL)
-      signal (SIGILL, handler);
+#if defined(SIGSYS)
+      signal (SIGSYS, backtrace_handler);
 #endif
 
-#if defined(SIGFPE)
-      signal (SIGFPE, handler);
+#if defined(SIGTRAP)
+      signal (SIGTRAP, backtrace_handler);
+#endif
+
+#if defined(SIGXCPU)
+      signal (SIGXCPU, backtrace_handler);
+#endif
+
+#if defined(SIGXFSZ)
+      signal (SIGXFSZ, backtrace_handler);
 #endif
     }
 #endif
@@ -140,7 +147,6 @@ init_compile_options (void)
     | GFC_STD_F2003 | GFC_STD_F2008 | GFC_STD_F95 | GFC_STD_F77
     | GFC_STD_F2008_OBS | GFC_STD_GNU | GFC_STD_LEGACY;
   compile_options.pedantic = 0;
-  compile_options.dump_core = 0;
   compile_options.backtrace = 0;
   compile_options.sign_zero = 1;
   compile_options.range_check = 1;

diff --git a/libgfortran/runtime/environ.c b/libgfortran/runtime/environ.c
index 7695f0db198e86ba323f74d24825c5fd5448b668..6bd88865d89b47d320aeecd7b0d1ef62275009f6 100644 (file)
--- a/libgfortran/runtime/environ.c
+++ b/libgfortran/runtime/environ.c
@@ -318,11 +318,6 @@ static variable variable_table[] = {
   {"GFORTRAN_CONVERT_UNIT", 0, 0, init_unformatted, show_string,
    "Set format for unformatted files", 0},
 
-  /* Behaviour when encoutering a runtime error.  */
-  {"GFORTRAN_ERROR_DUMPCORE", -1, &options.dump_core,
-    init_boolean, show_boolean,
-    "Dump a core file (if possible) on runtime error", -1},
-
   {"GFORTRAN_ERROR_BACKTRACE", -1, &options.backtrace,
     init_boolean, show_boolean,
     "Print out a backtrace (if possible) on runtime error", -1},
@@ -388,7 +383,7 @@ show_variables (void)
   estr_write ("\nCommand line arguments:\n");
   estr_write ("  --help               Print this list\n");
 
-  sys_exit (0);
+  exit (0);
 }
 
 /* This is the handling of the GFORTRAN_CONVERT_UNITS environment variable.

diff --git a/libgfortran/runtime/error.c b/libgfortran/runtime/error.c
index e61904496c8f802fcd7489100f98fa04171a04ca..dae298df203022c107a1978e56f921d58deb898c 100644 (file)
--- a/libgfortran/runtime/error.c
+++ b/libgfortran/runtime/error.c
@@ -58,44 +58,32 @@ see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
 #endif
 
 
-/* sys_exit()-- Terminate the program with an exit code.  */
-
-void
-sys_exit (int code)
-{
-  /* Show error backtrace if possible.  */
-  if (code != 0 && code != 4
-      && (options.backtrace == 1
-         || (options.backtrace == -1 && compile_options.backtrace == 1)))
-    show_backtrace ();
-
-  /* Dump core if requested.  */
-  if (code != 0
-      && (options.dump_core == 1
-        || (options.dump_core == -1 && compile_options.dump_core == 1)))
-    {
-#if defined(HAVE_GETRLIMIT) && defined(RLIMIT_CORE)
-      /* Warn if a core file cannot be produced because
-        of core size limit.  */
-
-      struct rlimit core_limit;
-
-      if (getrlimit (RLIMIT_CORE, &core_limit) == 0 && core_limit.rlim_cur == 0)
-       estr_write ("** Warning: a core dump was requested, but the core size"
-                  "limit\n**          is currently zero.\n\n");
-#endif
-      
-      
-#if defined(HAVE_KILL) && defined(HAVE_GETPID) && defined(SIGQUIT)
-      kill (getpid (), SIGQUIT);
-#else
-      estr_write ("Core dump not possible, sorry.");
-#endif
-    }
-
-  exit (code);
-}
-
+/* Termination of a program: F2008 2.3.5 talks about "normal
+   termination" and "error termination". Normal termination occurs as
+   a result of e.g. executing the end program statement, and executing
+   the STOP statement. It includes the effect of the C exit()
+   function. 
+
+   Error termination is initiated when the ERROR STOP statement is
+   executed, when ALLOCATE/DEALLOCATE fails without STAT= being
+   specified, when some of the co-array synchronization statements
+   fail without STAT= being specified, and some I/O errors if
+   ERR/IOSTAT/END/EOR is not present, and finally EXECUTE_COMMAND_LINE
+   failure without CMDSTAT=.
+
+   2.3.5 also explains how co-images synchronize during termination.
+
+   In libgfortran we have two ways of ending a program. exit(code) is
+   a normal exit; calling exit() also causes open units to be
+   closed. No backtrace or core dump is needed here. When something
+   goes wrong, we have sys_abort() which tries to print the backtrace
+   if -fbacktrace is enabled, and then dumps core; whether a core file
+   is generated is system dependent. When aborting, we don't flush and
+   close open units, as program memory might be corrupted and we'd
+   rather risk losing dirty data in the buffers rather than corrupting
+   files on disk.
+
+*/
 
 /* Error conditions.  The tricky part here is printing a message when
  * it is the I/O subsystem that is severely wounded.  Our goal is to
@@ -107,7 +95,6 @@ sys_exit (int code)
  * 1    Terminated because of operating system error.
  * 2    Error in the runtime library
  * 3    Internal error in runtime library
- * 4    Error during error processing (very bad)
  *
  * Other error returns are reserved for the STOP statement with a numeric code.
  */
@@ -150,7 +137,7 @@ st_vprintf (const char *format, va_list ap)
 #define ERROR_MESSAGE "Internal error: buffer overrun in st_vprintf()\n"
       write (STDERR_FILENO, buffer, ST_VPRINTF_SIZE - 1);
       write (STDERR_FILENO, ERROR_MESSAGE, strlen(ERROR_MESSAGE));
-      sys_exit(2);
+      sys_abort ();
 #undef ERROR_MESSAGE
 
     }
@@ -173,6 +160,27 @@ st_printf (const char * format, ...)
 }
 
 
+/* sys_abort()-- Terminate the program showing backtrace and dumping
+   core.  */
+
+void
+sys_abort ()
+{
+  /* If backtracing is enabled, print backtrace and disable signal
+     handler for ABRT.  */
+  if (options.backtrace == 1
+      || (options.backtrace == -1 && compile_options.backtrace == 1))
+    {
+      show_backtrace ();
+#if defined(HAVE_SIGNAL) && defined(SIGABRT)
+      signal (SIGABRT, SIG_DFL);
+#endif
+    }
+
+  abort();
+}
+
+
 /* gfc_xtoa()-- Integer to hexadecimal conversion.  */
 
 const char *
@@ -278,7 +286,7 @@ recursion_check (void)
 
   /* Don't even try to print something at this point */
   if (magic == MAGIC)
-    sys_exit (4);
+    sys_abort ();
 
   magic = MAGIC;
 }
@@ -300,7 +308,7 @@ os_error (const char *message)
   estr_write ("\n");
   estr_write (message);
   estr_write ("\n");
-  sys_exit (1);
+  exit (1);
 }
 iexport(os_error);
 
@@ -319,7 +327,7 @@ runtime_error (const char *message, ...)
   st_vprintf (message, ap);
   va_end (ap);
   estr_write ("\n");
-  sys_exit (2);
+  exit (2);
 }
 iexport(runtime_error);
 
@@ -338,7 +346,7 @@ runtime_error_at (const char *where, const char *message, ...)
   st_vprintf (message, ap);
   va_end (ap);
   estr_write ("\n");
-  sys_exit (2);
+  exit (2);
 }
 iexport(runtime_error_at);
 
@@ -376,7 +384,7 @@ internal_error (st_parameter_common *cmp, const char *message)
      because hopefully it doesn't happen too often).  */
   stupid_function_name_for_static_linking();
 
-  sys_exit (3);
+  exit (3);
 }
 
 
@@ -544,7 +552,7 @@ generate_error (st_parameter_common *cmp, int family, const char *message)
   estr_write ("Fortran runtime error: ");
   estr_write (message);
   estr_write ("\n");
-  sys_exit (2);
+  exit (2);
 }
 iexport(generate_error);
 
@@ -606,7 +614,7 @@ notify_std (st_parameter_common *cmp, int std, const char * message)
       estr_write ("Fortran runtime error: ");
       estr_write (message);
       estr_write ("\n");
-      sys_exit (2);
+      exit (2);
     }
   else
     {

diff --git a/libgfortran/runtime/stop.c b/libgfortran/runtime/stop.c
index b6f61ff8bee564b15cb0365b14fc3b92791c89c1..2efe23924e737406abbaf5d8822fd45d52d54daa 100644 (file)
--- a/libgfortran/runtime/stop.c
+++ b/libgfortran/runtime/stop.c
@@ -41,7 +41,7 @@ stop_numeric (GFC_INTEGER_4 code)
   else
     st_printf ("STOP %d\n", (int)code);
 
-  sys_exit (code);
+  exit (code);
 }
 
 
@@ -55,7 +55,7 @@ void
 stop_numeric_f08 (GFC_INTEGER_4 code)
 {
   st_printf ("STOP %d\n", (int)code);
-  sys_exit (code);
+  exit (code);
 }
 
 
@@ -71,7 +71,7 @@ stop_string (const char *string, GFC_INTEGER_4 len)
       (void) sizeof (w); /* Avoid compiler warning about not using w.  */
       estr_write ("\n");
     }
-  sys_exit (0);
+  exit (0);
 }
 
 
@@ -92,7 +92,7 @@ error_stop_string (const char *string, GFC_INTEGER_4 len)
   (void) sizeof (w); /* Avoid compiler warning about not using w.  */
   estr_write ("\n");
 
-  sys_exit (1);
+  sys_abort ();
 }
 
 
@@ -106,5 +106,8 @@ void
 error_stop_numeric (GFC_INTEGER_4 code)
 {
   st_printf ("ERROR STOP %d\n", (int) code);
-  sys_exit (code);
+  if (options.backtrace == 1
+      || (options.backtrace == -1 && compile_options.backtrace == 1))
+    show_backtrace ();
+  exit (code);
 }