https://gcc.gnu.org/bugzilla/show_bug.cgi?id=119913
Richard Biener <rguenth at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Target|x96_64 |x86_64-*-*
Status|UNCONFIRMED |RESOLVED
Resolution|--- |INVALID
--- Comment #2 from Richard Biener <rguenth at gcc dot gnu.org> ---
Note an uninitialized variable use is still UB, -ftrivial-auto-var-init=zero
does not make it well-defined. Quoting docs:
"GCC still considers an automatic variable that doesn't have an explicit
initializer as uninitialized, @option{-Wuninitialized} and
@option{-Wanalyzer-use-of-uninitialized-value} will still report
warning messages on such automatic variables and the compiler will
perform optimization as if the variable were uninitialized."
In particular
#if 0
int b = b1, c = c;
#else
int b, c;
#endif
has in both cases 'c' uninitialized.
