OpenE2K/gcc
2
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

2001-01-26 Andrew Haley <aph@redhat.com>

Browse Source 
(INIT_FPE): Use a direct system call to set the handler.

From-SVN: r39354
This commit is contained in:
Andrew Haley 2001-01-30 21:00:22 +00:00 committed by Andrew Haley
parent 1e738f74b9
commit cab1f90abf
2 changed files with 20 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
libjava/ChangeLog
View File

@ -1,3 +1,7 @@
2001-01-26 Andrew Haley <aph@redhat.com>
(INIT_FPE): Use a direct system call to set the handler.
2001-01-27 Richard Henderson <rth@redhat.com>
* configure.host (alpha*-*) [libgcj_flags]: Add -mieee.

18
libjava/include/i386-signal.h
View File

@ -1,6 +1,6 @@
// i386-signal.h - Catch runtime signals and turn them into exceptions.
/* Copyright (C) 1998, 1999 Free Software Foundation
/* Copyright (C) 1998, 1999, 2001 Free Software Foundation
This file is part of libgcj.
@ -17,6 +17,7 @@ details. */
#define JAVA_SIGNAL_H 1
#include <signal.h>
#include <sys/syscall.h>
#define HANDLE_SEGV 1
#define HANDLE_FPE 1
@ -140,9 +141,22 @@ do \
act.sa_handler = catch_fpe; \
sigemptyset (&act.sa_mask); \
act.sa_flags = 0; \
__sigaction (SIGFPE, &act, NULL); \
syscall (SYS_sigaction, SIGFPE, &act, NULL); \
} \
while (0)
/* You might wonder why we use syscall(SYS_sigaction) in INIT_FPE
* instead of the standard sigaction(). This is necessary because of
* the shenanigans above where we increment the PC saved in the
* context and then return. This trick will only work when we are
* called _directly_ by the kernel, because linuxthreads wraps signal
* handlers and its wrappers do not copy the sigcontext struct back
* when returning from a signal handler. If we return from our divide
* handler to a linuxthreads wrapper, we will lose the PC adjustment
* we made and return to the faulting instruction again. Using
* syscall(SYS_sigaction) causes our handler to be called directly by
* the kernel, bypassing any wrappers. This is a kludge, and a future
* version of this handler will do something better. */
#endif /* JAVA_SIGNAL_H */