[PATCH] D28772: [Preprocessor] Fix incorrect token caching that occurs when lexing _Pragma in macro argument pre-expansion mode when skipping a function body

[Richard Smith via Phabricator via cfe-commits]

rsmith added a comment.

Can we instead address this locally in `_Pragma` handling, by getting it to clear out the junk it inserted into the token stream when it's done (if backtracking is enabled)?


Repository:
  rL LLVM

https://reviews.llvm.org/D28772