https://gcc.gnu.org/bugzilla/show_bug.cgi?id=116907
--- Comment #21 from Eric Botcazou <ebotcazou at gcc dot gnu.org> ---
> So the TREE_BLOCK (expr) has been free'd.
Right. The TREE_BLOCK for an expression is:
if (IS_EXPR_CODE_CLASS (c))
return LOCATION_BLOCK (t->exp.locus);
and "locus" is just an integer so the GC marking probably stops there.
