[Bug tree-optimization/123298] [9 - 16 Regression] X86-64: miscompile at -O3

[mikpelinux at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=123298

Mikael Pettersson <mikpelinux at gmail dot com> changed:

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--- Comment #1 from Mikael Pettersson <mikpelinux at gmail dot com> ---
Created attachment 63153
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=63153&action=edit
cleaned up test case

Cleaned up test case, compiles without warnings, -fsanitize=undefined is
silent.
Triggers at -O3 with gcc-9 to 16 inclusive. -O2 is fine. gcc-8 is fine at both
-O2 and -O3. Same behaviour on x86_64 and aarch64.