Summary:
The cache recorded the wrong expansion location for all but the first
stringization. It seems uncommon to stringize the same macro argument
multiple times, so this cache doesn't seem that important.
Fixes PR39942
Reviewers: vsk, rsmith
Subscribers: cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D65428
llvm-svn: 367337
Reid Kleckner