https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97878
--- Comment #5 from CVS Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Jakub Jelinek <ja...@gcc.gnu.org>: https://gcc.gnu.org/g:b229baa75ce4627d1bd38f2d3dcd91af1a7071db commit r11-7120-gb229baa75ce4627d1bd38f2d3dcd91af1a7071db Author: Jakub Jelinek <ja...@redhat.com> Date: Fri Feb 5 10:22:07 2021 +0100 c++: Fix ICE with structured binding initialized to incomplete array [PR97878] We ICE on the following testcase, for incomplete array a on auto [b] { a }; without giving any kind of diagnostics, with auto [c] = a; during error-recovery. The problem is that we get too far through check_initializer and e.g. store_init_value -> constexpr stuff can't deal with incomplete array types. As the type of the structured binding artificial variable is always deduced, I think it is easiest to diagnose this early, even if they have array types we'll need their deduced type to be complete rather than just its element type. 2021-02-05 Jakub Jelinek <ja...@redhat.com> PR c++/97878 * decl.c (check_array_initializer): For structured bindings, require the array type to be complete. * g++.dg/cpp1z/decomp54.C: New test.