https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111505
--- Comment #5 from Sergei Trofimovich <slyfox at gcc dot gnu.org> --- (In reply to Sergei Trofimovich from comment #4) > Is it a ggc_common_finalize() bug in assuming that `base` does not point to > the bbeginning of a struct? > Or a `gt_ggc_r_gt_cp_tree_h` bug that it does not point to the beginning of > the struct? > > Also while at it: what should `ggc_common_finalize ()` ideally do to > `ovl_op_info`? memset() all of it? Or only pointers? I think it has > information only to do latter but it does it in a very strange way. Proposed fix as https://gcc.gnu.org/pipermail/gcc-patches/2023-September/631634.html . That fixes `profiledbootstrap` for me. Having stared a bit more at gcc/ggc-common.cc the answer is: it's complicated. There are 3 roots: gt_ggc_rtab gt_ggc_deletable_rtab gt_pch_scalar_rtab Last two are simple: these are single-element complete values without complexities. But gt_ggc_rtab is different: it encodes pointer locations within structs (of non-pointers). GCH code carefully extracts and restores those pointers. An example: for (rt = gt_ggc_rtab; *rt; rt++) for (rti = *rt; rti->base != NULL; rti++) for (i = 0; i < rti->nelt; i++) (*rti->pchw)(*(void **)((char *)rti->base + rti->stride * i)); finalize() should do the same.
