MaskRay added a comment. > The !associated metadata may be attached to a global object declaration with > a single argument that references another global object. This metadata > prevents discarding of the global object in linker GC unless the referenced > object is also discarded.
"prevents discarding" is not accurate in the context. `__llvm_prf_*` cannot be discarded because C identifier name input sections are GC roots. Add "C identifier name input sections are GC roots. In LLD, the SHF_LINK_ORDER flag overrides the C identifier name semantics." in appropriate place. > Furthermore, when a function symbol is discarded by the linker, setting up > !associated metadata allows linker to discard counters, data and values > associated with that function symbol. This is not possible today because > there's metadata to guide the linker. This approach is also used by other > instrumentations like sanitizers. This C identifier name GC currently only works with LLD but does no harm to gold/GNU ld. Do you think `__llvm_prf_*` can link to the text section so that the self-link trick is not needed? (https://sourceware.org/bugzilla/show_bug.cgi?id=27259) CHANGES SINCE LAST ACTION https://reviews.llvm.org/D76802/new/ https://reviews.llvm.org/D76802 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
