1.9.9x releases (tried 91-95) fail to build on x86_64 because gpg2 segfaults
during the openpgp test:

../../g10/gpg2 --homedir . --quiet --yes --no-permission-warning --import ./pubd
emo.asc
gpg: NOTE: THIS IS A DEVELOPMENT VERSION!
gpg: It is only intended for test purposes and should NOT be
gpg: used in a production environment or with production keys!

gpg: signal Segmentation fault caught ... exiting
make[3]: * [prepared.stamp] Segmentation fault
make[3]: Leaving directory `/usr/src/ark/BUILD/gnupg-1.9.95/tests/openpgp'
make[2]: * [all-recursive] Error 1

strace ends in:

open("tests/openpgp/pubdemo.asc", O_RDONLY) = 3
read(3, "26 demo keys:\n\npub 1024D/686977"..., 8192) = 8192
read(3, "y4AqjewlkkTOQevLwtzwm3pmLLjl2Y3T"..., 8192) = 8192

ltrace says:
read(3, "y4AqjewlkkTOQevLwtzwm3pmLLjl2Y3T"..., 8192) = 8192
gcry_xcalloc(1, 168, 0xffffffff, 2, 3) = 0x6a5c40
gcry_pk_algo_info(17, 16, 0, 0x7fff83f54cf0, 0) = 0
gcry_pk_algo_info(17, 15, 0, 0x7fff83f54cf0, 0xfefefefefefefeff) = 0
gcry_xmalloc(130, 1024, 10, 10, 0x6a3b20) = 0x6a5cf0
gcry_mpi_scan(0x7fff83f54cb8, 2, 0x6a5cf0, 258, 0x7fff83f54cc4) = 0
gcry_free(0x6a5cf0, 0x6a5da0, 16, 0x6a5da0, 0x49f3d4fa9ff26abb) = 145

• SIGSEGV (Segmentation fault) ---

gcry_control(25, 0x7fff83f54bf0, 0x7fff83f54ac0, 0, 0x6a5cf0) = 0
write(2, "\n", 1
) = 1
strlen("gpg") = 3
write(2, "gpg", 3gpg) = 3
write(2, ": signal ", 9: signal ) = 9
strlen("Segmentation fault") = 18
write(2, "Segmentation fault", 18Segmentation fault) = 18
write(2, " caught ... exiting\n", 20 caught ... exiting
) = 20
sigemptyset(0x7fff83f54938) = 0
sigaction(11, 0x7fff83f54930, NULL) = 0
raise(11, 0x7fff83f54870, 0, -1, 0) = 0

gnupg 1.9.95
libgcrypt 1.2.2
libgpg-error 1.4
libksba 1.0.0
libassuan 0.9.3
glibc 2.5
gcc 4.2
binutils 2.17.50.0.3
linux 2.6.18

(identical set of libraries and toolchain on x86 works ok).