Created attachment 62000 [details] build.log.xz ``` [...] Configuring in ./gnattools configure: loading cache ./config.cache checking for a BSD-compatible install... /usr/lib/portage/python3.13/ebuild-helpers/xattr/install -c checking build system type... x86_64-pc-linux-gnu checking host system type... x86_64-pc-linux-gnu checking target system type... x86_64-pc-linux-gnu checking for x86_64-pc-linux-gnu-gcc... /var/tmp/portage/sys-devel/gcc-16.0.9999/work/build/./gcc/xgcc -B/var/tmp/portage/sys-devel/gcc-16.0.9999/work/build/./gcc/ -B/usr/x86_64-pc-linux-gnu/bin/ -B/usr/x86_64-pc-linux-gnu/lib/ -isystem /usr/x86_64-pc-linux-gnu/include -isystem /usr/x86_64-pc-linux-gnu/sys-include -fchecking=1 checking whether the C compiler works... no configure: error: in `/var/tmp/portage/sys-devel/gcc-16.0.9999/work/build/gnattools': configure: error: C compiler cannot create executables See `config.log' for more details make[1]: *** [Makefile:13962: configure-gnattools] Error 1 make[1]: Leaving directory '/var/tmp/portage/sys-devel/gcc-16.0.9999/work/build' [...] config.status: executing gstdint.h commands make[1]: Leaving directory '/var/tmp/portage/sys-devel/gcc-16.0.9999/work/build' make: *** [Makefile:30927: bootstrap-lean] Error 2 * ERROR: sys-devel/gcc-16.0.9999::gentoo failed (compile phase): * emake failed ``` I don't have the config.log anymore, sorry, but it was straightforward with ``` $ /var/tmp/portage/sys-devel/gcc-16.0.9999/work/build/./gcc/xgcc -B/var/tmp/portage/sys-devel/gcc-16.0.9999/work/build/./gcc/ -B/usr/x86_64-pc-linux-gnu/bin/ -B/usr/x86_64-pc-linux-gnu/lib/ -isystem /usr/x86_64-pc-linux-gnu/include -isystem /usr/x86_64-pc-linux-gnu/sys-include -fchecking=1 -g -g1 -O2 -D_GENTOO_TIME64_FORCE=0 -static-libstdc++ -static-libgcc -fsanitize=undefined -static-libubsan -DUBSAN_BOOTSTRAP -B/var/tmp/portage/sys-devel/gcc-16.0.9999/work/build/prev-x86_64-pc-linux-gnu/libsanitizer/ -B/var/tmp/portage/sys-devel/gcc-16.0.9999/work/build/prev-x86_64-pc-linux-gnu/libsanitizer/ubsan/ -B/var/tmp/portage/sys-devel/gcc-16.0.9999/work/build/prev-x86_64-pc-linux-gnu/libsanitizer/ubsan/.libs -Wl,-O1 conftest.c ``` failing b/c it couldn't find libsanitizer.spec. It existed in previous bulid dirs but not in build/gcc. It looks to me like with bootstrap-ubsan, if you don't have the same compiler version already installed w/ libsanitizer, then in some cases, libsanitizer.spec and libubsan.a might not be found because there isn't anything forcing a dependency on libcc1, gnattools etc on libsanitizer? Copying libsanitizer.spec and libubsan.a into /var/tmp/portage/sys-devel/gcc-16.0.9999/work/build/gcc fixed it.
In bootstrap-ubsan.mk, we do: ``` POSTSTAGE1_LDFLAGS += -fsanitize=undefined -static-libubsan -DUBSAN_BOOTSTRAP \ -B$$r/prev-$(TARGET_SUBDIR)/libsanitizer/ \ -B$$r/prev-$(TARGET_SUBDIR)/libsanitizer/ubsan/ \ -B$$r/prev-$(TARGET_SUBDIR)/libsanitizer/ubsan/.libs ``` I think those -B workaround the problem for everything but stage3? You can't hit this in stage2 because of those lines, at least.
Sorry, ignore the last comment.