Ignore unknown pragmas.

In particular, we are looking to ignore the "#pragma mark" construct which GCC
warns about on platforms other than Darwin.  This cleans up diagnostic output
significantly.



git-svn-id: https://llvm.org/svn/llvm-project/llvdb/trunk@122974 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed