[PATCH] D26483: CMake: make LLVM_OPTIMIZED_TABLEGEN friendly with LLVM_EXTERNAL_CLANG_SOURCE_DIR

[Chris Bieneman via llvm-commits]

beanz added a comment.

You should only set this if the variable is set, otherwise it will set the variable to empty and CMake's bad caching behavior will leave you stuck with that.


https://reviews.llvm.org/D26483