The sanitizer backtrace is used in tests, and calling StackTrace.Print() means that it uses the sanitizer's Printf(), rather than GWP-ASan's Printf(). In the current code, GWP-ASan's Printf() *is* the sanitizer print, but this isn't guaranteed to be the case, and will change in an upcoming patch. Reviewed By: eugenis Differential Revision: https://reviews.llvm.org/D139748