https://gcc.gnu.org/bugzilla/show_bug.cgi?id=119175
--- Comment #3 from GCC Commits <cvs-commit at gcc dot gnu.org> --- The trunk branch has been updated by Jason Merrill <ja...@gcc.gnu.org>: https://gcc.gnu.org/g:39892d9618ee0f06dd09271589878b0df7b1e75d commit r15-9362-g39892d9618ee0f06dd09271589878b0df7b1e75d Author: Jason Merrill <ja...@redhat.com> Date: Wed Apr 9 13:22:56 2025 -0400 c++: lambda in constraint of lambda [PR119175] Here when we went to mangle the constraints of from<0>, the outer lambda has no mangling scope, but the inner one was treated as having the outer one as its scope. And mangling the outer one means mangling its constraints, which include the inner one. So infinite recursion. But a lambda closure type isn't a scope that anything should have for mangling, the inner lambda should also have no mangling scope. PR c++/119175 gcc/cp/ChangeLog: * mangle.cc (decl_mangling_context): Look through lambda type. gcc/testsuite/ChangeLog: * g++.dg/cpp2a/concepts-lambda23.C: New test.
