https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98250
Bug ID: 98250
Summary: Wrong code path with -O1 and signed overflow
Product: gcc
Version: 10.2.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c
Assignee: unassigned at gcc dot gnu.org
Reporter: stransky.peter at googlemail dot com
Target Milestone: ---
Wrong code path after signed overflow in gcc-10 and optimization > O1.
Problem seems to be introduced somewhere between gcc-6 and gcc-8.
#include <stdio.h>
void foo(int n) {
if (n > 0)
{
++n;
printf("n=%d\n", n);
if(n > 0) {
printf("Should not get here.\n");
}
}
}
int main() {
foo(0x7fffffff);
return 0;
}
g++ issue.cc -o issue && ./issue
n=-2147483648
g++ issue.cc -o issue -O1 && ./issue
n=-2147483648
Should not get here.
