Hi, when putting together a patch to fix PR 43812 I wanted to extend the call graph verifier to verify that
1) the same_comdat_group linked lists are indeed circular, 2) there are no one element lists, and 3) all nodes in such lists have the flag DECL_COMDAT (node->decl) set. However, the third property is currently violated when building libstc++, at first I thought that we drop the flag without evicting the associated nodes from a list but it is not so. The C++ front-end actually adds a node to a same_comdat_group list even though the corresponding function decl does not have DECL_COMDAT set - however it does have a non-NULL DECL_COMDAT_GROUP. This happens at cp/optimize.c:436. So my question essentially is: Is this a bug or are DECL_COMDAT same_comdat_group and DECL_COMDAT_GROUP (un)related in some other way? For now, I'll drop the verification from th patch (which is attached in bugzilla). However, it would be nice to formulate relevant invariants precisely and verify them, lest we will be bumping into bugs like this one. Thanks, Martin
