[Bug modula2/105390] New: [12 regression] sigfpe redeclared in mc-boot-ch/GSysExceptions.c

["ro at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105390

            Bug ID: 105390
           Summary: [12 regression] sigfpe redeclared in
                    mc-boot-ch/GSysExceptions.c
           Product: gcc
           Version: 12.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: modula2
          Assignee: gaius at gcc dot gnu.org
          Reporter: ro at gcc dot gnu.org
  Target Milestone: ---
            Target: *-*-solaris2.11

Building the devel/modula-2 branch on Solaris fails with

/vol/gcc/src/hg/master/modula-2/gcc/m2/mc-boot-ch/GSysExceptions.c:89:25:
error: 'sigaction sigfpe' redeclared as different kind of entity
   89 | static struct sigaction sigfpe;
      |                         ^~~~~~
In file included from
/var/gcc/gcc-12.0.1-20220424/11.4-gm2/prev-gcc/include-fixed/math.h:391,
                 from
/var/gcc/gcc-12.0.1-20220424/11.4-gm2/prev-sparc-sun-solaris2.11/libstdc++-v3/include/bits/std_abs.h:40,
                 from
/var/gcc/gcc-12.0.1-20220424/11.4-gm2/prev-sparc-sun-solaris2.11/libstdc++-v3/include/cstdlib:77,
                 from
/var/gcc/gcc-12.0.1-20220424/11.4-gm2/prev-sparc-sun-solaris2.11/libstdc++-v3/include/stdlib.h:36,
                 from /vol/gcc/src/hg/master/modula-2/gcc/system.h:265,
                 from
/vol/gcc/src/hg/master/modula-2/gcc/m2/mc-boot-ch/GSysExceptions.c:23:
/usr/include/floatingpoint.h:64:28: note: previous declaration 'void (*
sigfpe(sigfpe_code_type, sigfpe_handler_type))()'
   64 | extern sigfpe_handler_type sigfpe __P((sigfpe_code_type,
sigfpe_handler_type));
      |                            ^~~~~~
In file included from /usr/include/sys/procset.h:17,
                 from /usr/include/sys/wait.h:22,
                 from /usr/include/stdlib.h:16,
                 from
/var/gcc/gcc-12.0.1-20220424/11.4-gm2/prev-sparc-sun-solaris2.11/libstdc++-v3/include/cstdlib:75:
/vol/gcc/src/hg/master/modula-2/gcc/m2/mc-boot-ch/GSysExceptions.c: In function
'void SysExceptions_InitExceptionHandlers(void (*)(void*), void (*)(void*),
void (*)(void*), void (*)(void*), void (*)(void*), void (*)(void*), void
(*)(void*), void (*)(void*), void (*)(void*), void (*)(void*), void (*)(void*),
void (*)(void*), void (*)(void*), void (*)(void*), void (*)(void*))':
/vol/gcc/src/hg/master/modula-2/gcc/m2/mc-boot-ch/GSysExceptions.c:203:10:
error: request for member '_funcptr' in 'sigfpe', which is of non-class type
'void (*(sigfpe_code_type, sigfpe_handler_type))()' {aka 'void (*(int, void
(*)()))()'}
  203 |   sigfpe.sa_sigaction = sigfpeDespatcher;
      |          ^~~~~~~~~~~~
/vol/gcc/src/hg/master/modula-2/gcc/m2/mc-boot-ch/GSysExceptions.c:204:10:
error: request for member 'sa_flags' in 'sigfpe', which is of non-class type
'void (*(sigfpe_code_type, sigfpe_handler_type))()' {aka 'void (*(int, void
(*)()))()'}
  204 |   sigfpe.sa_flags = (SA_SIGINFO);
      |          ^~~~~~~~
/vol/gcc/src/hg/master/modula-2/gcc/m2/mc-boot-ch/GSysExceptions.c:205:24:
error: request for member 'sa_mask' in 'sigfpe', which is of non-class type
'void (*(sigfpe_code_type, sigfpe_handler_type))()' {aka 'void (*(int, void
(*)()))()'}
  205 |   sigemptyset (&sigfpe.sa_mask);
      |                        ^~~~~~~

/vol/gcc/src/hg/master/modula-2/gcc/m2/mc-boot-ch/GSysExceptions.c:207:26:
error: cannot convert 'void (* (*)(sigfpe_code_type, sigfpe_handler_type))()'
{aka 'void (* (*)(int, void (*)()))()'} to 'const sigaction*'
  207 |   if (sigaction (SIGFPE, &sigfpe, &old) != 0)
      |                          ^~~~~~~
      |                          |
      |                          void (* (*)(sigfpe_code_type,
sigfpe_handler_type))() {aka void (* (*)(int, void (*)()))()}
In file included from /vol/gcc/src/hg/master/modula-2/gcc/system.h:432:
/usr/include/signal.h:46:27: note:   initializing argument 2 of 'int
sigaction(int, const sigaction*, sigaction*)'
   46 | extern int sigaction(int, const struct sigaction *_RESTRICT_KYWD,
      |                           ^

The same issue exists in gm2-libs-ch/SysExceptions.c.

I've worked around this by renaming sigfpe to sigfpe_.