================ @@ -161,8 +161,13 @@ static TypeCode getTypeCodeForTypeClass(Type::TypeClass id) { namespace { -std::set<const FileEntry *> GetAffectingModuleMaps(const Preprocessor &PP, - Module *RootModule) { +std::optional<std::set<const FileEntry *>> +GetAffectingModuleMaps(const Preprocessor &PP, Module *RootModule) { + // Without implicit module map search, there's no good reason to know about + // any module maps that are not affecting. + if (!PP.getHeaderSearchInfo().getHeaderSearchOpts().ImplicitModuleMaps) + return std::nullopt; ---------------- zygoloid wrote:
Yes, that sounds great, thank you. In our case, it's not that the module map files are unused, it's that we specify the same `-fmodule-map-file=` flag to all of our compilations, and so we *usually* get the information from a `.pcm` file rather than from the module map file, and it turns out that pruning out the repeated module maps make a rather large difference to our source location address space usage :) All that said, we have some other ideas for how to address the problems we're seeing with source location address space usage. Maybe we can get to a point where we're not relying on this at all -- I think this patch is probably the right behavior, even though I think it's contributing to a regression for us, so I think this new behavior should be the default, and we can clean up the flag once we don't need it any more. https://github.com/llvm/llvm-project/pull/87849 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits