https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87813
--- Comment #9 from Martin Sebor <msebor at gcc dot gnu.org> ---
(In reply to Aldy Hernandez from comment #6)
I agree, but it's just a small subset of such cases. There are many optimizing
transformations that GCC does at -O0 that affect the IL later on: calls to
library built-ins are folded into other library calls (strcpy to memcpy), or to
MEM_REFs (memcpy), or even to constants (strlen). For example:
int f (void)
{
return __builtin_strlen ("123");
}