https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108206
--- Comment #6 from CVS Commits <cvs-commit at gcc dot gnu.org> --- The releases/gcc-12 branch has been updated by Jakub Jelinek <ja...@gcc.gnu.org>: https://gcc.gnu.org/g:7048e8c1073fcf2bf6be1a3d079393a78864ca61 commit r12-9137-g7048e8c1073fcf2bf6be1a3d079393a78864ca61 Author: Jakub Jelinek <ja...@redhat.com> Date: Wed Jan 4 18:42:31 2023 +0100 c++: Error recovery in merge_default_template_args [PR108206] We ICE on the following testcase during error recovery, both new_parm and old_parm are error_mark_node, the ICE is on error ("redefinition of default argument for %q+#D", new_parm); inform (DECL_SOURCE_LOCATION (old_parm), "original definition appeared here"); where we don't print anything useful for new_parm and ICE trying to access DECL_SOURCE_LOCATION of old_parm. I think we shouldn't diagnose anything when either of the parms is erroneous, GCC 11 before merge_default_template_args has been added was doing if (TREE_VEC_ELT (tmpl_parms, i) == error_mark_node || TREE_VEC_ELT (parms, i) == error_mark_node) continue; tmpl_parm = TREE_VALUE (TREE_VEC_ELT (tmpl_parms, i)); if (error_operand_p (tmpl_parm)) return false; in redeclare_class_template. 2023-01-04 Jakub Jelinek <ja...@redhat.com> PR c++/108206 * decl.cc (merge_default_template_args): Return false if either new_parm or old_parm are erroneous. * g++.dg/template/pr108206.C: New test. (cherry picked from commit fc349931adcf1024ee95e0a0cd98cf4a41996093)
