https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91451
Bug ID: 91451
Summary: Do not warn about duplicate __STDC_WANT_* definitions
Product: gcc
Version: 9.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: preprocessor
Assignee: unassigned at gcc dot gnu.org
Reporter: jsm28 at gcc dot gnu.org
Target Milestone: ---
GCC warns by default about duplicate (identical) definitions of __STDC_*
macros, but has special code to avoid doing so for __STDC_FORMAT_MACROS,
__STDC_LIMIT_MACROS and __STDC_CONSTANT_MACROS as those are intended for the
user to define (see bug 32868 and bug 34859). The same special logic should
apply to __STDC_WANT_* macros, which are also macros specified by the C
standard and various TS documents as for the user to define. (I think it's
best to apply that to all __STDC_WANT_* rather than a fixed list of such
macros.)
