[PATCH] D36458: Fix crash when current lexer is nullptr

[Ivan Donchevskii via Phabricator via cfe-commits]

yvvan added a comment.

But I don't know the source of that issue, I only know how to fix it because I caught that one in debugger and added a check to prevent it.
How can I write testcase for such fix?


https://reviews.llvm.org/D36458