[PATCH] D51789: [WIP][clang] Add the no_extern_template attribute

[Richard Smith - zygoloid via Phabricator via cfe-commits]

rsmith added a comment.

It'd be good to test that `[[no_extern_template]]` affects instantiation, not just code generation (eg, put something in the body of the entity that will trigger an error if instantiated, and check that the diagnostic is produced at the right times).


Repository:
  rL LLVM

https://reviews.llvm.org/D51789