Previously these would be transformed into annotation tokens and the
preprocessor would then assume they were real tokens with source
locations and assert/UB.
Other pragmas that produce annotation tokens aren't a problem because
they aren't handled if the parser isn't hooked up - ParsePragma.cpp
registers those handlers & isn't run for pure preprocessing. So they're
treated as unknown pragmas & printed verbatim by the preprocessor.
Perhaps these pragmas should be treated the same way? But they got mixed
in with other __debug pragmas that do need to be handled during
preprocessing.
The third __debug pragma that produces an annotation token is 'captured'
- which had its own fix for this issue - by not inserting the annotation
token in the first place if it detected that it was in preprocessing
mode. I've removed that fix (from Lex/Pragma.cpp) in favor of the more
general one in Frontend/PrintPreprocessedOutput.cpp.
llvm-svn: 346928
David Blaikie