https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101782
--- Comment #2 from Jonathan Wakely <redi at gcc dot gnu.org> --- I think we can probably do this to stop the test failing: --- a/gcc/testsuite/g++.dg/cpp2a/concepts-pr67774.C +++ b/gcc/testsuite/g++.dg/cpp2a/concepts-pr67774.C @@ -1,5 +1,4 @@ // { dg-do compile { target c++20 } } -// { dg-additional-options "-fconcepts-ts" } #include <type_traits> #include <utility> Because that flag was present to enable concepts support, but concepts are always enabled for c++20 now, and it gets run with -std=c++2a But the FE bug still needs to be fixed.