https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106687
Bug ID: 106687
Summary: [13 Regression] Wrong code with -O2
Product: gcc
Version: 13.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: tree-optimization
Assignee: unassigned at gcc dot gnu.org
Reporter: vsevolod.livinskiy at gmail dot com
Target Milestone: ---
Link to the Compiler Explorer: https://godbolt.org/z/a8PTr5sqM
The error disappears if I use another definition of max (b > p2 ? b : p2).
Reproducer:
#include <stdio.h>
bool var_0 = (bool)0;
unsigned int var_7 = 42;
char var_215;
const unsigned &a(const unsigned &b, unsigned &p2) { return b < p2 ? p2 : b; }
void test() { var_215 = a(var_0, var_7) ^ (var_7 - var_0) ?: 42; }
int main() {
test();
printf("%d\n", var_215);
if (var_215 != 42)
__builtin_abort();
}
Error:
>$ g++ -O1 small.cpp && ./a.out
42
>$ g++ -O2 small.cpp && ./a.out
0
Aborted (core dumped)
gcc version 13.0.0 20220819 (81e20a6eb9e6b7eb62a09ac58811387f0343bd14)
