The following code should abort at runtime when compiled with -ftrapv: #include <limits.h>
int __attribute__((noinline)) iaddv (int a, int b) { return a + b; } int main(void) { iaddv (INT_MAX, 1); return 0; } It doesn't in 64-bit mode: [EMAIL PROTECTED] native]$ gcc-4.0 -o addv addv.c -ftrapv [EMAIL PROTECTED] native]$ ./addv [EMAIL PROTECTED] native]$ gcc-4.0 -o addv addv.c -ftrapv -m32 [EMAIL PROTECTED] native]$ ./addv Aborted The problem originates in .03.jump: the libcall to __addvdi3 is eliminated. -- Summary: addition on integers doesn't trap Product: gcc Version: 4.0.0 Status: UNCONFIRMED Severity: normal Priority: P2 Component: rtl-optimization AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: ebotcazou at gcc dot gnu dot org CC: gcc-bugs at gcc dot gnu dot org GCC build triplet: x86_64-*-* GCC host triplet: x86_64-*-* GCC target triplet: x86_64-*-* http://gcc.gnu.org/bugzilla/show_bug.cgi?id=19020