mirrors/qemu
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

oslib-posix: Fix new compiler error with -Wclobbered

Browse Source 
Newer versions of gcc report a warning (or an error with -Werror) when
compiler option -Wclobbered (or -Wextra) is active:

util/oslib-posix.c:372:12: error:
 variable ‘hpagesize’ might be clobbered by ‘longjmp’ or ‘vfork’ [-Werror=clobbered]

The rewritten code fixes this warning: variable 'hpagesize' is now set and
used in a block without any call of sigsetjmp or similar functions.

Signed-off-by: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Stefan Weil 2014-06-24 22:52:29 +02:00 committed by Paolo Bonzini
parent 8248c36a5d
commit b7bf8f5657
1 changed files with 16 additions and 14 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

30
util/oslib-posix.c
View File

@ -366,10 +366,9 @@ static size_t fd_getpagesize(int fd)
void os_mem_prealloc(int fd, char *area, size_t memory)
{
int ret, i;
int ret;
struct sigaction act, oldact;
sigset_t set, oldset;
size_t hpagesize = fd_getpagesize(fd);
memset(&act, 0, sizeof(act));
act.sa_handler = &sigbus_handler;
@ -389,19 +388,22 @@ void os_mem_prealloc(int fd, char *area, size_t memory)
if (sigsetjmp(sigjump, 1)) {
fprintf(stderr, "os_mem_prealloc: failed to preallocate pages\n");
exit(1);
}
} else {
int i;
size_t hpagesize = fd_getpagesize(fd);
/* MAP_POPULATE silently ignores failures */
memory = (memory + hpagesize - 1) & -hpagesize;
for (i = 0; i < (memory/hpagesize); i++) {
memset(area + (hpagesize*i), 0, 1);
}
/* MAP_POPULATE silently ignores failures */
memory = (memory + hpagesize - 1) & -hpagesize;
for (i = 0; i < (memory / hpagesize); i++) {
memset(area + (hpagesize * i), 0, 1);
}
ret = sigaction(SIGBUS, &oldact, NULL);
if (ret) {
perror("os_mem_prealloc: failed to reinstall signal handler");
exit(1);
}
ret = sigaction(SIGBUS, &oldact, NULL);
if (ret) {
perror("os_mem_prealloc: failed to reinstall signal handler");
exit(1);
}
pthread_sigmask(SIG_SETMASK, &oldset, NULL);
pthread_sigmask(SIG_SETMASK, &oldset, NULL);
}
}