https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99899
--- Comment #2 from CVS Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Patrick Palka <ppa...@gcc.gnu.org>: https://gcc.gnu.org/g:66de517b1c1dd22df7914f8e9a083cd5a73adbe2 commit r11-7997-g66de517b1c1dd22df7914f8e9a083cd5a73adbe2 Author: Patrick Palka <ppa...@redhat.com> Date: Mon Apr 5 23:35:56 2021 -0400 c++: placeholder type constraint in structured binding [PR99899] In this PR, we're crashing because the constraint handling inside do_auto_deduction doesn't expect to see an adc_decomp_type context. This patch fixes this by treating adc_decomp_type like adc_variable_type or adc_return_type during placeholder type constraint checking. Meanwhile, I noticed we weren't checking constraints at all when binding an array via a structured binding, since do_auto_deduction would exit early and bypass the constraint check. This patch fixes this by replacing the early exit with an appropriate setup of the 'targs' vector. gcc/cp/ChangeLog: PR c++/99899 * pt.c (do_auto_deduction): Don't exit early when deducing the array type of a structured binding. Also handle adc_decomp_type during constraint checking. gcc/testsuite/ChangeLog: PR c++/99899 * g++.dg/cpp2a/concepts-placeholder7.C: New test. * g++.dg/cpp2a/concepts-placeholder8.C: New test.
