https://gcc.gnu.org/bugzilla/show_bug.cgi?id=119756
Bug ID: 119756 Summary: Error when reading source from stdin and compiling modules: cc1plus: fatal error: stdout: No such file or directory Product: gcc Version: 15.0 Status: UNCONFIRMED Severity: minor Priority: P3 Component: c++ Assignee: unassigned at gcc dot gnu.org Reporter: redi at gcc dot gnu.org Target Milestone: --- This works: :| ~/gcc/15/bin/g++ -x c++ - -x c++ /dev/null -c -std=c++20 It creates -.o and null.o as expected. But if you add -fmodules -fsearch-include-path ../include/c++/15.0.1/bits/std.compat.cc then it fails: :| ~/gcc/15/bin/g++ -x c++ - -x c++ /dev/null -c -std=c++20 -fmodules \ -fsearch-include-path ../include/c++/15.0.1/bits/std.compat.cc cc1plus: fatal error: stdout: No such file or directory compilation terminated. In module imported at /home/jwakely/gcc/15/include/c++/15.0.1/bits/std.compat.cc:30:8: std: error: failed to read compiled module: No such file or directory std: note: compiled module file is ‘gcm.cache/std.gcm’ std: note: imports must be built before being imported std: fatal error: returning to the gate for a mechanical issue compilation terminated. It looks like something about using '-' as the input causes the module code to use the string 'stdout' as the output.