📄 setjmp-2.c
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/* PR middle-end/17813 *//* Origin: Tom Hughes <tom@compton.nu> *//* { dg-do run { target i?86-*-linux* x86_64-*-linux* } } *//* { dg-options "-O -fomit-frame-pointer" } *//* { dg-options "-O -fomit-frame-pointer -march=i386" { target { { i?86-*-* x86_64-*-* } && ilp32 } } } */#include <setjmp.h>#include <signal.h>#include <stdlib.h>static jmp_buf segv_jmpbuf;static void segv_handler(int seg){ __builtin_longjmp(segv_jmpbuf, 1);}static int is_addressable(void *p, size_t size){ volatile char * volatile cp = (volatile char *)p; volatile int ret; struct sigaction sa, origsa; sigset_t mask; sa.sa_handler = segv_handler; sa.sa_flags = 0; sigfillset(&sa.sa_mask); sigaction(SIGSEGV, &sa, &origsa); sigprocmask(SIG_SETMASK, NULL, &mask); if (__builtin_setjmp(segv_jmpbuf) == 0) { while(size--) *cp++; ret = 1; } else ret = 0; sigaction(SIGSEGV, &origsa, NULL); sigprocmask(SIG_SETMASK, &mask, NULL); return ret;}int main(int argc, char **argv){ is_addressable(0x0, 1); return 0;}
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