https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96160
--- Comment #4 from plevine457 at gmail dot com --- The offending command is > /var/tmp/portage/sys-devel/gcc-10.1.0-r1/work/build/./gcc/xgcc > -B/var/tmp/portage/sys-devel/gcc-10.1.0-r1/work/build/./gcc/ -xc++ -nostdinc > /dev/null -S -o /dev/null > -fself-test=/var/tmp/portage/sys-devel/gcc-10.1.0-r1/work/gcc-10.1.0/gcc/testsuite/selftests I would presume that there's no reason why gcc would emit "-o /dev/null" though I have seen it whaile using ccache. Looking further at https://github.com/buildroot/buildroot/commit/58ecbbc3ef18c43ae1c02a5c4bf30aa7ef2d8092, with regard to s-selftest-c: > The problem only occurs when ccache is used with gcc 9 and 10, > probably due to a race condition. > > While debuging with "make -p" we can notice that s-selftest-c target > contain only "cc1" as dependency instead of cc1 and SELFTEST_DEPS [4]. > > s-selftest-c: cc1 > > While the build is failing, the s-selftest-c dependencies recipe is > still running and reported as a bug by make. > > "Dependencies recipe running (THIS IS A BUG)." > > A change [5] in gcc 9 seems to introduce the problem since we can't > reproduce this problem with gcc 8. So this is likely a ccache bug.
