https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64610
Bug ID: 64610 Summary: No -Wbool-compare warning on "(0 != a) >= 0" Product: gcc Version: 5.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: c Assignee: unassigned at gcc dot gnu.org Reporter: chengniansun at gmail dot com There is no warning on the expression "(0 != a) >= 0". I think the cause of this bug is different from the one I reported just now (PR64609). $: cat s.c int a; void fn1() { ((0 != a) >= 0); } $: $: gcc-trunk -Wbool-compare -c s.c $: $: clang-trunk -Wno-unused-value -c s.c s.c:2:24: warning: comparison of constant 0 with boolean expression is always true [-Wtautological-constant-out-of-range-compare] void fn1() { ((0 != a) >= 0); } ~~~~~~~~ ^ ~ 1 warning generated. $: $: