https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99737
--- Comment #2 from Alexander Lelyakin <alexander.lelyakin at googlemail dot com> --- This error is very unstable. Each found sequence is not reproducible after few commits. But some other sequence appears with similar message. This time such a sequence is: /usr/local/bin/g++ -std=c++20 -fmodules-ts -x c++-system-header algorithm /usr/local/bin/g++ -std=c++20 -fmodules-ts -x c++-system-header memory /usr/local/bin/g++ -std=c++20 -fmodules-ts -x c++-system-header thread /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 istream /usr/local/bin/g++ -std=c++20 -fmodules-ts -x c++-system-header variant /usr/local/bin/g++ -std=c++20 -fmodules-ts -x c++-system-header functional /usr/local/bin/g++ -std=c++20 -fmodules-ts -x c++-system-header cassert /usr/local/bin/g++ -std=c++20 -fmodules-ts -x c++-system-header cinttypes /usr/local/bin/g++ -std=c++20 -fmodules-ts -x c++-system-header shared_mutex /usr/local/bin/g++ -std=c++20 -fmodules-ts -x c++-system-header locale /usr/local/bin/g++ -std=c++20 -fmodules-ts -x c++-system-header fstream /usr/local/bin/g++ -std=c++20 -fmodules-ts -x c++-system-header cwctype /usr/local/bin/g++ -std=c++20 -fmodules-ts -x c++-system-header exception /usr/local/bin/g++ -std=c++20 -fmodules-ts -x c++-system-header cstdlib /usr/local/bin/g++ -std=c++20 -fmodules-ts -x c++-system-header string /usr/local/bin/g++ -std=c++20 -fmodules-ts -x c++-system-header vector /usr/local/bin/g++ -std=c++20 -fmodules-ts -x c++-system-header cstdio /usr/local/bin/g++ -std=c++20 -fmodules-ts -x c++-system-header filesystem ---- malloc(): smallbin double linked list corrupted In file included from /usr/local/include/c++/11.0.1/bits/shared_ptr_base.h:53, from /usr/local/include/c++/11.0.1/bits/shared_ptr.h:53, from /usr/local/include/c++/11.0.1/bits/fs_path.h:46, from /usr/local/include/c++/11.0.1/filesystem:45: /usr/local/include/c++/11.0.1/bits/allocated_ptr.h: In destructor ‘std::__allocated_ptr<_Alloc>::~__allocated_ptr()’: /usr/local/include/c++/11.0.1/bits/allocated_ptr.h:73:32: internal compiler error: Aborted 73 | std::allocator_traits<_Alloc>::deallocate(*_M_alloc, _M_ptr, 1); | ^ 0x110151f crash_signal ../../gcc/gcc/toplev.c:327 0x1d47510 xrealloc ../../gcc/libiberty/xmalloc.c:179 0xa8eb0d void va_heap::reserve<cp_token*>(vec<cp_token*, va_heap, vl_embed>*&, unsigned int, bool) ../../gcc/gcc/vec.h:290 0xa8eb0d vec<cp_token*, va_heap, vl_ptr>::reserve(unsigned int, bool) ../../gcc/gcc/vec.h:1778 0xa8eb0d vec<cp_token*, va_heap, vl_ptr>::safe_push(cp_token* const&) ../../gcc/gcc/vec.h:1887 0xa8eb0d cp_lexer_save_tokens ../../gcc/gcc/cp/parser.c:1241 0xa8eb0d cp_parser_parse_tentatively ../../gcc/gcc/cp/parser.c:32847 0xabe86d cp_parser_type_name ../../gcc/gcc/cp/parser.c:19219 0xacb256 cp_parser_simple_type_specifier ../../gcc/gcc/cp/parser.c:18924 0xaa9e5d cp_parser_type_specifier ../../gcc/gcc/cp/parser.c:18516 0xabbc23 cp_parser_type_specifier_seq ../../gcc/gcc/cp/parser.c:23367 0xaba2a4 cp_parser_type_id_1 ../../gcc/gcc/cp/parser.c:23170 0xabc893 cp_parser_template_type_arg ../../gcc/gcc/cp/parser.c:23275 0xabc9bf cp_parser_template_argument ../../gcc/gcc/cp/parser.c:17915 0xabc9bf cp_parser_template_argument_list ../../gcc/gcc/cp/parser.c:17826 0xabc9bf cp_parser_enclosed_template_argument_list ../../gcc/gcc/cp/parser.c:30799 0xabdcec cp_parser_template_id ../../gcc/gcc/cp/parser.c:17398 0xabe3eb cp_parser_class_name ../../gcc/gcc/cp/parser.c:24692 0xab595a cp_parser_qualifying_entity ../../gcc/gcc/cp/parser.c:7002 0xab595a cp_parser_nested_name_specifier_opt ../../gcc/gcc/cp/parser.c:6684 Please submit a full bug report, with preprocessed source if appropriate. Please include the complete backtrace with any bug report. See <https://gcc.gnu.org/bugs/> for instructions. ---- g++ (GCC) 11.0.1 20210327 (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. commit 651684b462f979a4e70a668c4c9767a5fd7d223a (HEAD -> master, origin/trunk, origin/master, origin/HEAD) Author: GCC Administrator <gccad...@gcc.gnu.org> Date: Sat Mar 27 00:16:27 2021 +0000 Daily bump.