https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68971
--- Comment #8 from Paul Eggert <eggert at gnu dot org> --- (In reply to Martin Sebor from comment #7) > Perhaps what's needed is for GCC to treat the builtins as constant > expressions when they're invoked with them as operands. If you agree with > that approach, I suggest closing this bug and opening a new one with that > request. Yes, I already filed a bug report along these lines, as Bug#68120. > because sophisticated warnings that try to avoid > issuing false positives for unreachable code (e.g., -Wmaybe-uninutialized) > depend on optimizations they tend to be inconsistent not only between > optimization settings but also between different targets. Yes, that issue is well known. We generally work around the problem by enabling fancy warnings only on one platform (x86-64) with known settings, and not bothering with other platforms. A corollary of this practice is that warning-related GCC bugs tend not to be reported or fixed on platforms other than x86-64. However, this workaround does not suffice for -Woverflow because -Woverflow is enabled by default. This raises the priority of getting -Woverflow right.
