https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97388
--- Comment #5 from CVS Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Jason Merrill <ja...@gcc.gnu.org>: https://gcc.gnu.org/g:8895443a42db4045aad8e4b42cd5dd2ad6ffa7d7 commit r11-4542-g8895443a42db4045aad8e4b42cd5dd2ad6ffa7d7 Author: Jason Merrill <ja...@redhat.com> Date: Wed Oct 28 17:30:05 2020 -0400 c++: Fix constexpr cleanup error handling. In this testcase, the primary evaluation successfully produces 'true', and then running one of the cleanups hits a double delete, making the whole thing not a valid constant expression. So we were returning 'true' wrapped in a NOP_EXPR to indicate its non-constancy, but evaluating that again is a perfectly acceptable constant expression, so we weren't getting the verbose diagnostic we were looking for. So if non_constant_p gets set other than for overflow, go back to the original expression. With this change, we should never hit the manifestly_const_eval test, and the is-constant-evaluated1.C test passes without it. gcc/cp/ChangeLog: PR c++/97388 * constexpr.c (cxx_eval_outermost_constant_expr): Revert to original expression if evaluation sets non_constant_p. gcc/testsuite/ChangeLog: PR c++/97388 * g++.dg/cpp2a/constexpr-dtor8.C: New test.
