[Bug target/52205] New: SPARC Solaris 2.11 unwind through signal handler fails with -fnon-call-exceptions

[ian at airs dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52205

             Bug #: 52205
           Summary: SPARC Solaris 2.11 unwind through signal handler fails
                    with -fnon-call-exceptions
    Classification: Unclassified
           Product: gcc
           Version: 4.7.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: target
        AssignedTo: unassig...@gcc.gnu.org
        ReportedBy: i...@airs.com
                CC: r...@gcc.gnu.org


Compile this C++ program with -fnon-call-exceptions:

#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

void
die(const char* msg)
{
  perror(msg);
  exit(EXIT_FAILURE);
}

void
handler(int signo, siginfo_t* info, void *context)
{
  printf("in handler signal %d\n", signo);
  throw signo;
}

int
main(int, const char**)
{
  struct sigaction act;
  memset(&act, 0, sizeof act);
  act.sa_sigaction = handler;
  sigfillset(&act.sa_mask);
  act.sa_flags = SA_SIGINFO;
  if (sigaction(SIGSEGV, &act, NULL) != 0)
    die("sigaction");

  try
    {
      *reinterpret_cast<char*>(0) = 1;
    }
  catch (int signo)
    {
      printf("caught signal %d\n", signo);
      exit(EXIT_SUCCESS);
    }

  printf("did not catch\n");
  exit(EXIT_FAILURE);
}

When this program is run, it should print something like

in handler signal 11
caught signal 11

This works fine on GNU/Linux and on x86 and x86_64 Solaris 2.11.  When run on
SPARC Solaris 2.11, however, it prints

in handler signal 11
Segmentation Fault

I see this in both 32-bit and 64-bit mode.  If I tweak
libgcc/config/sparc/sol2-unwind.h so that sparc_is_sighandler sets *nframes to
3 rather than 2, then the test passes (I only tried this in 32-bit mode, not in
64-bit mode).  The cuh_pattern test in sparc_is_sighandler does not match, so
presumably it needs to be adjusted for Solaris 2.11.  However, I'm not sure how
to properly and safely correct it.