https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91212
--- Comment #9 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:81bc0ec3e926d7a2c90502847ddaacf3d56d5b75 commit r11-2411-g81bc0ec3e926d7a2c90502847ddaacf3d56d5b75 Author: Jason Merrill <ja...@redhat.com> Date: Wed Jul 29 00:57:40 2020 -0400 c++: Avoid calling const copy ctor on implicit move. [PR91212] Our implementation of C++11 implicit move was wrong for return; we didn't actually hit the check for the type of the first parameter of the selected constructor, because we didn't see LOOKUP_PREFER_RVALUE set properly. Fixing that to look at the right flags fixed the issue for this testcase, but broke implicit move for a by-value converting constructor (PR58051). I think this was not allowed in C++17, but it is allowed under the implicit move changes from C++20, and those changes were voted to apply as a DR to earlier standards as well, so I don't want to break it now. So after fixing the flags check I changed the test to allow value parameters. gcc/cp/ChangeLog: PR c++/91212 * call.c (build_over_call): Don't call a const ref overload for implicit move. gcc/testsuite/ChangeLog: PR c++/91212 * g++.dg/cpp0x/move-return3.C: New test.
