https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99496
--- Comment #5 from seurer at gcc dot gnu.org --- Just running the compilation doesn't work as it requires some stuff that must be generated earlier. In module imported at /home/seurer/gcc/git/gcc-test/gcc/testsuite/g++.dg/modules/xtreme-header-3_c.C:3:1: /home/seurer/gcc/git/gcc-test/gcc/testsuite/g++.dg/modules/xtreme-header-3_a.H: error: failed to read compiled module: No such file or directory /home/seurer/gcc/git/gcc-test/gcc/testsuite/g++.dg/modules/xtreme-header-3_a.H: note: compiled module file is 'gcm.cache/./home/seurer/gcc/git/gcc-test/gcc/testsuite/g++.dg/modules/xtreme-header-3_a.H.gcm' /home/seurer/gcc/git/gcc-test/gcc/testsuite/g++.dg/modules/xtreme-header-3_a.H: note: imports must be built before being imported /home/seurer/gcc/git/gcc-test/gcc/testsuite/g++.dg/modules/xtreme-header-3_a.H: fatal error: returning to the gate for a mechanical issue The mentioned file is not left around anywhere I see.