ax_check_catchable_segv.m4 (1587B)
1 # SYNOPSIS 2 # 3 # AX_CHECK_CATCHABLE_SEGV 4 # 5 # DESCRIPTION 6 # 7 # Check whether segmentation violations can be caught using signal handlers. 8 9 #serial 1 10 11 AC_DEFUN([AX_CHECK_CATCHABLE_SEGV], [dnl 12 AC_PREREQ(2.64) 13 AS_VAR_PUSHDEF([CACHEVAR], [ax_cv_check_[]_AC_LANG_ABBREV[]CATCHABLE_SEGV])dnl 14 AC_CACHE_CHECK([whether segmentation violations can be caught], CACHEVAR, [ 15 AC_RUN_IFELSE([ 16 AC_LANG_PROGRAM([[ 17 #include <signal.h> 18 #include <stdlib.h> 19 static void sig(int _) { exit(0); } 20 ]], [[ 21 volatile unsigned char * volatile x = (volatile unsigned char *) malloc(8); 22 size_t i; 23 24 #ifdef SIGPROT 25 signal(SIGPROT, sig); 26 #endif 27 signal(SIGSEGV, sig); 28 signal(SIGBUS, sig); 29 #if !defined(__SANITIZE_ADDRESS__) && !defined(__EMSCRIPTEN__) 30 *((volatile unsigned char *) -1) = 0xd0; 31 *((volatile unsigned char *) 1) = 0xd0; 32 for (i = 0; i < 10000000; i += 1024) { x[-i] = x[i] = (unsigned char) i; } 33 #endif 34 free((void *) x); 35 exit(1) 36 ]])], 37 [AS_VAR_SET(CACHEVAR, [yes])], 38 [AS_VAR_SET(CACHEVAR, [no])], 39 [AS_VAR_SET(CACHEVAR, [unknown])] 40 ) 41 ]) 42 AS_VAR_IF(CACHEVAR, yes, 43 [AC_DEFINE([HAVE_CATCHABLE_SEGV], [1], [Define if segmentation violations can be caught using signal handlers])], 44 [AC_MSG_WARN([On this platform, segmentation violations cannot be caught using signal handlers. This is expected if you enabled a tool such as Address Sanitizer (-fsanitize=address), but be aware that using Address Sanitizer may also significantly reduce performance.])] 45 ) 46 AS_VAR_POPDEF([CACHEVAR])dnl 47 ])