https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98642
--- Comment #2 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:d75199f782348bfc401f925b60f33ffc9822b7cc commit r11-6736-gd75199f782348bfc401f925b60f33ffc9822b7cc Author: Jason Merrill <ja...@redhat.com> Date: Wed Jan 13 13:27:06 2021 -0500 c++: Avoid redundant copy in {} init [PR98642] Here, initializing from { } implies a call to the default constructor for base. We were then seeing that we're initializing a base subobject, so we tried to copy the result of that call. This is clearly wrong; we should initialize the base directly from its default constructor. This patch does a lot of refactoring of unsafe_copy_elision_p and adds make_safe_copy_elision that will also try to do the base constructor rewriting from the last patch. gcc/cp/ChangeLog: PR c++/98642 * call.c (unsafe_return_slot_p): Return int. (init_by_return_slot_p): Split out from... (unsafe_copy_elision_p): ...here. (unsafe_copy_elision_p_opt): New name for old meaning. (build_over_call): Adjust. (make_safe_copy_elision): New. * typeck2.c (split_nonconstant_init_1): Elide copy from safe list-initialization. * cp-tree.h: Adjust. gcc/testsuite/ChangeLog: PR c++/98642 * g++.dg/cpp1z/elide5.C: New test.
