Improved support for removing the comma preceding __VA_ARGS__ where __VA_ARGS__
is empty in a variadic macro expansion.  This fixes a divergence in support for
the ", ## __VA_ARGS__" GCC extension which differed in behaviour when in strict
C99 mode (note: there is no change in behaviour has been made in the gnu99 mode
that clang uses by default).  In addition, there is improved support for the
Microsoft alternative extension ", __VA_ARGS__".

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@167613 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed