https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98471
Bug ID: 98471 Summary: libstdc++ fails to build with clang on windows because of filesystem bug Product: gcc Version: 11.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: c++ Assignee: unassigned at gcc dot gnu.org Reporter: unlvsur at live dot com Target Milestone: --- Created attachment 49849 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=49849&action=edit working patch to fix the issue #include<filesystem> int main() { } D:\hg\fast_io\.tmp>clang++ -o filesystem filesystem.cc -Ofast -std=c++20 -s In file included from filesystem.cc:1: In file included from D:\msys64\mingw64\include\c++\11.0.0\filesystem:45: D:\msys64\mingw64\include\c++\11.0.0\bits/fs_path.h:252:15: error: invalid use of incomplete type 'std::filesystem::filesystem_error' throw filesystem_error( ^~~~~~~~~~~~~~~~~ D:\msys64\mingw64\include\c++\11.0.0\bits/fs_fwd.h:58:9: note: forward declaration of 'std::filesystem::filesystem_error' class filesystem_error; ^ In file included from filesystem.cc:1: In file included from D:\msys64\mingw64\include\c++\11.0.0\filesystem:45: D:\msys64\mingw64\include\c++\11.0.0\bits/fs_path.h:252:9: error: cannot throw object of incomplete type 'std::filesystem::filesystem_error' throw filesystem_error( ^ ~~~~~~~~~~~~~~~~~ D:\msys64\mingw64\include\c++\11.0.0\bits/fs_fwd.h:58:9: note: forward declaration of 'std::filesystem::filesystem_error' class filesystem_error; ^ 2 errors generated.