https://gcc.gnu.org/bugzilla/show_bug.cgi?id=116730
--- Comment #36 from Jonathan Wakely <redi at gcc dot gnu.org> --- Where do your broken symlinks point to, if not the correct sources? I still can't reproduce it with "make install" so I've removed --disable-bootstrap from my configure options and am waiting for a bootstrap now. It doesn't work to replace the symlinks with: VPATH = $(top_srcdir)../libbacktrace $(top_srcdir)../libiberty and using the relative paths for the files in the SOURCES variable gives a warning as noted in the commit message of the commit referenced above. It's possible that the existence of libbacktrace and libstdc++-v3/src/libbacktrace with the same name in the source tree confuses automake. Maybe renaming the latter would help.
