Introduce __has_extension macro

__has_extension is a function-like macro which takes the same set
of feature identifiers as __has_feature.  It evaluates to 1 if the
feature is supported by Clang in the current language (either as a
language extension or a standard language feature) or 0 if not.

At the same time, add support for the C1X feature identifiers
c_generic_selections (renamed from generic_selections) and
c_static_assert, and document them.

Patch by myself and Jean-Daniel Dupas.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@131308 91177308-0d34-0410-b5e6-96231b3b80d8

0 files changed, 0 insertions, 0 deletions