https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63731
--- Comment #20 from Yohei Ueda <yohei at jp dot ibm.com> --- I noticed a Docker issue saying GC 1.4 does not rebuild the standard library with -a. https://github.com/docker/docker/issues/9449 I think the problem is now not limited to GCCGO.