libgcrypt1.9.0: Failure on linking test executables

[Kasumi Fukuda]

Dear gcrypt developers,

I'm trying to build libgcrypt 1.9.0 on amazonlinux2, with its
dependency library (libgpg-error) built from source and installed in a
non-default prefixed location (and libgcrypt-config is on the $PATH
when configure).
The test executables such as tests/t-secmem and tests/t-mpi-bit fail
to link in my environment with the following error:

----
/bin/sh ../libtool  --tag=CC   --mode=link gcc
-I/opt/x86_64-redhat-linux/libgpg-error/1.41/include -g -O2
-fvisibility=hidden -fno-delete-null-pointer-checks -Wall -no-install
-o t-secmem t-secmem.o ../src/libgcrypt.la ../compat/libcompat.la
libtool: link: gcc
-I/opt/x86_64-redhat-linux/libgpg-error/1.41/include -g -O2
-fvisibility=hidden -fno-delete-null-pointer-checks -Wall -o t-secmem
t-secmem.o  ../src/.libs/libgcrypt.so ../compat/.libs/libcompat.a
-Wl,-rpath -Wl,/tmp/src/tmp/x86_64-redhat-linux/ports/libgcrypt/1.9.0/libgcrypt-1.9.0/src/.libs
-Wl,-rpath -Wl,/opt/x86_64-redhat-linux/libgcrypt/1.9.0/lib
../src/.libs/libgcrypt.so: undefined reference to `gpgrt_fprintf at GPG_ERROR_1.0'
../src/.libs/libgcrypt.so: undefined reference to
`gpg_err_code_from_syserror at GPG_ERROR_1.0'
../src/.libs/libgcrypt.so: undefined reference to
`gpgrt_get_syscall_clamp at GPG_ERROR_1.0'
../src/.libs/libgcrypt.so: undefined reference to
`gpgrt_lock_init at GPG_ERROR_1.0'
../src/.libs/libgcrypt.so: undefined reference to
`gpg_err_code_from_errno at GPG_ERROR_1.0'
../src/.libs/libgcrypt.so: undefined reference to
`gpgrt_lock_unlock at GPG_ERROR_1.0'
../src/.libs/libgcrypt.so: undefined reference to
`gpgrt_b64dec_start at GPG_ERROR_1.0'
../src/.libs/libgcrypt.so: undefined reference to `gpgrt_rewind at GPG_ERROR_1.0'
../src/.libs/libgcrypt.so: undefined reference to
`gpgrt_b64dec_finish at GPG_ERROR_1.0'
../src/.libs/libgcrypt.so: undefined reference to
`gpgrt_lock_lock at GPG_ERROR_1.0'
../src/.libs/libgcrypt.so: undefined reference to
`gpg_err_set_errno at GPG_ERROR_1.0'
../src/.libs/libgcrypt.so: undefined reference to `gpg_strsource at GPG_ERROR_1.0'
../src/.libs/libgcrypt.so: undefined reference to `gpgrt_fclose at GPG_ERROR_1.0'
../src/.libs/libgcrypt.so: undefined reference to
`gpgrt_b64dec_proc at GPG_ERROR_1.0'
../src/.libs/libgcrypt.so: undefined reference to `gpgrt_fopenmem at GPG_ERROR_1.0'
../src/.libs/libgcrypt.so: undefined reference to `gpg_strerror at GPG_ERROR_1.0'
../src/.libs/libgcrypt.so: undefined reference to
`gpgrt_fclose_snatch at GPG_ERROR_1.0'
../src/.libs/libgcrypt.so: undefined reference to `gpgrt_ferror at GPG_ERROR_1.0'
../src/.libs/libgcrypt.so: undefined reference to
`gpgrt_lock_destroy at GPG_ERROR_1.0'
collect2: error: ld returned 1 exit status
make[2]: *** [t-secmem] Error 1
----

Seeing the log, I think we need to specify the location of
libgpg-error for the linker to correctly link these executables.
Commenting out the following lines in tests/Makefile.am seems to fix
the problem (these lines overrides LDADD to drop -lgcrypt-error):

----
pkbench_LDADD = $(standard_ldadd)
prime_LDADD = $(standard_ldadd)
t_mpi_bit_LDADD = $(standard_ldadd)
t_secmem_LDADD = $(standard_ldadd)
testapi_LDADD = $(standard_ldadd)
----

I will provide the full configure/make logs if necessary.