Fix Clang's __DEPRECATED define to be controled by -Wdeprecated. This
matches GCC behavior which libstdc++ uses to limit #warning-based
messages about deprecation.

The machinery involves threading this through a new '-fdeprecated-macro'
flag for CC1. The flag defaults to "on", similarly to -Wdeprecated. We
turn the flag off in the driver when the warning is turned off (modulo
matching some GCC bugs). We record this as a language option, and key
the preprocessor on the option when introducing the define.

A separate flag rather than a '-D' flag allows us to properly represent
the difference between C and C++ builds (only C++ receives the define),
and it allows the specific behavior of following -Wdeprecated without
potentially impacting the set of user-provided macro flags.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@130055 91177308-0d34-0410-b5e6-96231b3b80d8
7 files changed