https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67433
Markus Trippelsdorf <trippels at gcc dot gnu.org> changed:
What |Removed |Added
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CC| |trippels at gcc dot gnu.org
--- Comment #9 from Markus Trippelsdorf <trippels at gcc dot gnu.org> ---
(In reply to xuejuncao from comment #8)
> thanks, i get the below result with -fsanitize=undefined
>
> boolmagic.c:12:16: runtime error: load of value 255, which is not a valid
> value for type '_Bool'
> boolmagic.c:13:15: runtime error: load of value 255, which is not a valid
> value for type '_Bool'
> boolmagic.c:14:15: runtime error: load of value 255, which is not a valid
> value for type '_Bool'
> b = 1, i = 1, j = 1
>
> but, can i say the "-fsanitize=undefined" will _corrects_ the undefined
> behaviour?
>
> or replace the code by if/else, which works fine (lucky?)
>
> int i; // = (u.b ? 1 : 0);
> if (u.b) i = 1; else i = 0;
No, you're still invoking undefined behavior. -fsanitize=undefined will not
fix this at all; it just points out the issues.
You need to get rid of the underlying problem, but this is not the place
to discuss this further.
