https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96383
--- Comment #17 from rguenther at suse dot de <rguenther at suse dot de> --- On Fri, 31 Jul 2020, jakub at gcc dot gnu.org wrote: > https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96383 > > --- Comment #15 from Jakub Jelinek <jakub at gcc dot gnu.org> --- > Unless we want for C/C++ to emit DW_AT_external DIEs for all function > prototypes that appear in the TU, we need ME help, because only there we > analyze the callgraph and prune cgraph nodes that are unreachable. Well, not sure - FEs do quite a good job with unused warnings by simply tracking things with TREE_USED so I guess global extern decls can be tracked as used/unused as well by FEs and what is a use (and worth emitting debug for) may be better decided by the FE, say for offsetof (X, m) we maybe want debug info for X even if it is not otherwise used?
