https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99479
--- Comment #5 from Alexander Lelyakin <alexander.lelyakin at googlemail dot com> --- There is a shorter sequence: ---- /usr/local/bin/g++ -std=c++20 -fmodules-ts -x c++-system-header cwchar /usr/local/bin/g++ -std=c++20 -fmodules-ts -x c++-system-header cmath /usr/local/bin/g++ -std=c++20 -fmodules-ts -x c++-system-header type_traits /usr/local/bin/g++ -std=c++20 -fmodules-ts -x c++-system-header condition_variable /usr/local/bin/g++ -std=c++20 -fmodules-ts -x c++-system-header future ---- corrupted double-linked list corrupted double-linked list g++: internal compiler error: Aborted signal terminated program cc1plus Please submit a full bug report, with preprocessed source if appropriate. See <https://gcc.gnu.org/bugs/> for instructions. ---- g++ (GCC) 11.0.1 20210324 (experimental) Copyright (C) 2021 Free Software Foundation, Inc. This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.