libgpg-error, libgcrypt, libassuan, gpgme and libksba don't allow 'make check' with the particular library being built, when rpath doesn't wok well.
(npth does.)
This is due to having AM_LDFLAGS = -no-install in tests/Makefile.am.
If it's good to support 'make check' with not-yet-installed library, let us remove the line. Doing this, it will work even if rpath doesn't work well. That's because with no -no-install, libtool will create wrapper script with LD_LIBRARY_PATH.
I know that it's only the particular library in question, and the cause of this problem is not ours but binutils and libtool.
It's true that when we do for libraries in bootstrap process, installing library is required.