[Bug fortran/31189] Support backtracing for non-library errors
--- Comment #6 from fxcoudert at gcc dot gnu dot org 2007-08-12 20:13 --- Fixed, thanks Tobias for the first version of the patch. -- fxcoudert at gcc dot gnu dot org changed: What|Removed |Added Status|ASSIGNED|RESOLVED Resolution||FIXED http://gcc.gnu.org/bugzilla/show_bug.cgi?id=31189
[Bug fortran/31189] Support backtracing for non-library errors
--- Comment #5 from fxcoudert at gcc dot gnu dot org 2007-08-11 21:52 --- Subject: Bug 31189 Author: fxcoudert Date: Sat Aug 11 21:52:22 2007 New Revision: 127364 URL: http://gcc.gnu.org/viewcvs?root=gccview=revrev=127364 Log: PR fortran/31189 * runtime/backtrace.c (show_backtrace): Skip _gfortrani_handler when displaying backtrace. * runtime/compile_options.c: Include signal.h. (handler): New function. (set_options): Set signal handlers for backtrace. * libgfortran.h (handler): Add prototype. * invoke.texi (-fbacktrace): Document the new behaviour. Modified: trunk/gcc/fortran/ChangeLog trunk/gcc/fortran/invoke.texi trunk/libgfortran/ChangeLog trunk/libgfortran/libgfortran.h trunk/libgfortran/runtime/backtrace.c trunk/libgfortran/runtime/compile_options.c -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=31189
[Bug fortran/31189] Support backtracing for non-library errors
--- Comment #4 from fxcoudert at gcc dot gnu dot org 2007-08-04 18:49
---
Thanks Tobias for the patch, here's an updated version that I intend to submit
for review...
Index: runtime/backtrace.c
===
--- runtime/backtrace.c (revision 127184)
+++ runtime/backtrace.c (working copy)
@@ -223,7 +223,8 @@ show_backtrace (void)
/* Try to recognize the internal libgfortran functions. */
if (strncasecmp (func, *_gfortran, 10) == 0
|| strncasecmp (func, _gfortran, 9) == 0
- || strcmp (func, main) == 0 || strcmp (func, _start) == 0)
+ || strcmp (func, main) == 0 || strcmp (func, _start) == 0
+ || strcmp (func, _gfortrani_handler) == 0)
continue;
if (local_strcasestr (str[i], libgfortran.so) != NULL
Index: libgfortran.h
===
--- libgfortran.h (revision 127184)
+++ libgfortran.h (working copy)
@@ -373,6 +373,9 @@ options_t;
extern options_t options;
internal_proto(options);
+extern void handler (int);
+internal_proto(handler);
+
/* Compile-time options that will influence the library. */
Index: runtime/compile_options.c
===
--- runtime/compile_options.c (revision 127184)
+++ runtime/compile_options.c (working copy)
@@ -31,10 +31,61 @@ Boston, MA 02110-1301, USA. */
#include libgfortran.h
+#ifdef HAVE_SIGNAL_H
+#include signal.h
+#endif
+
/* Useful compile-time options will be stored in here. */
compile_options_t compile_options;
+
+/* A signal handler to allow us to output a backtrace. */
+void
+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);
+}
+
+
/* Set the usual compile-time options. */
extern void set_options (int , int []);
export_proto(set_options);
@@ -56,6 +107,31 @@ set_options (int num, int options[])
compile_options.sign_zero = options[5];
if (num = 7)
compile_options.bounds_check = options[6];
+
+ /* If backtrace is required, we set signal handlers on most common
+ signals. */
+#if defined(HAVE_SIGNAL_H) (defined(SIGSEGV) || defined(SIGBUS) \
+ || defined(SIGILL) || defined(SIGFPE))
+ if (compile_options.backtrace)
+{
+#if defined(SIGSEGV)
+ signal (SIGSEGV, handler);
+#endif
+
+#if defined(SIGBUS)
+ signal (SIGBUS, handler);
+#endif
+
+#if defined(SIGILL)
+ signal (SIGILL, handler);
+#endif
+
+#if defined(SIGFPE)
+ signal (SIGFPE, handler);
+#endif
+}
+#endif
+
}
--
fxcoudert at gcc dot gnu dot org changed:
What|Removed |Added
AssignedTo|unassigned at gcc dot gnu |fxcoudert at gcc dot gnu dot
|dot org |org
Status|NEW |ASSIGNED
Last reconfirmed|2007-03-17 11:36:17 |2007-08-04 18:49:39
date||
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=31189
[Bug fortran/31189] Support backtracing for non-library errors
--- Comment #2 from burnus at gcc dot gnu dot org 2007-05-15 15:17 --- *** Bug 31936 has been marked as a duplicate of this bug. *** -- burnus at gcc dot gnu dot org changed: What|Removed |Added CC||dfranke at gcc dot gnu dot ||org http://gcc.gnu.org/bugzilla/show_bug.cgi?id=31189
[Bug fortran/31189] Support backtracing for non-library errors
--- Comment #3 from burnus at gcc dot gnu dot org 2007-05-15 17:31 --- Created an attachment (id=13558) -- (http://gcc.gnu.org/bugzilla/attachment.cgi?id=13558action=view) Patch Since PR 30498 is fixed, gfortran supports backtraces. However, they are only displayed for library errors not for, e.g., SEGV or signalling IEEE signals. A support for these can be found embedded in the patch at http://gcc.gnu.org/ml/gcc-patches/2007-02/msg00747.html I extracted the non-committed parts of that patch. Confirmed. We have to be careful how that interacts with user-installed signal handlers, but it's otherwise a good idea. I think this should be no problem. They are set very early before any user command has been set. If a user uses signal, he can install a user handler instead which overwrites the handler in libgfortran, which is probably what the user wants. This covers: SIGSEGV, SIGILL, SIGFPE and SIGBUS Examples: a) uninitialized integer pointer: integer, pointer :: i; i = 5 Program received signal SIGILL: Segmentation fault Backtrace for this error: + /lib64/libc.so.6 [0x2af232dbf410] + function _fini (0x40084B) b) Division by zero with -ffpe-trap=zero Program received signal SIGFPE: Segmentation fault Backtrace for this error: + /lib64/libc.so.6 [0x2b20b66d3410] + in the main program at line 5 of file x.f90 + /lib64/libc.so.6(__libc_start_main+0xf4) [0x2b20b66c0944] For (a) the backtrace using gdb is similarly useless. -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=31189
[Bug fortran/31189] Support backtracing for non-library errors
--- Comment #1 from fxcoudert at gcc dot gnu dot org 2007-03-17 11:36 --- Confirmed. We have to be careful how that interacts with user-installed signal handlers, but it's otherwise a good idea. -- fxcoudert at gcc dot gnu dot org changed: What|Removed |Added Status|UNCONFIRMED |NEW Ever Confirmed|0 |1 Last reconfirmed|-00-00 00:00:00 |2007-03-17 11:36:17 date|| http://gcc.gnu.org/bugzilla/show_bug.cgi?id=31189
