https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110977
Bug ID: 110977
Summary: Should -fms-extensions define _MSC_EXTENSIONS?
Product: gcc
Version: 13.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c
Assignee: unassigned at gcc dot gnu.org
Reporter: aaron at aaronballman dot com
Target Milestone: ---
This macro is predefined by MSVC when their extensions are enabled (/Ze in
cl.exe, on by default):
https://learn.microsoft.com/en-us/cpp/preprocessor/predefined-macros?view=msvc-170
However, GCC does not define the macro when enabling Microsoft extensions. See
https://godbolt.org/z/MqKTz6ob7 for a reproducer.
Clang also does not define this macro when passing -fms-extensions, but we're
investigating defining the macro in this case
(https://reviews.llvm.org/D157334); if Clang goes that route, would GCC do the
same or are there reasons you're not defining this macro that we should be
aware of?
