Building 0.15.1 on up to date Debian/sid (with libtasn 2.14 from experimental) I get a testsuite error:
-----------------------------
(SID)ametzler@argenau:/tmp/P11-KIT/p11-kit-0.15.1$ ./common/tests/test-attrs
Segmentation fault
(SID)ametzler@argenau:/tmp/P11-KIT/p11-kit-0.15.1$ gdb ./common/tests/test-attrs
GNU gdb (GDB) 7.4.1-debian
Copyright (C) 2012 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.  Type "show copying"
and "show warranty" for details.
This GDB was configured as "i486-linux-gnu".
For bug reporting instructions, please see:
<http://www.gnu.org/software/gdb/bugs/>...
Reading symbols from /tmp/P11-KIT/p11-kit-0.15.1/common/tests/test-attrs...done.
(gdb) run
Starting program: /tmp/P11-KIT/p11-kit-0.15.1/common/tests/test-attrs
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/i386-linux-gnu/libthread_db.so.1".

Program received signal SIGSEGV, Segmentation fault.
0x0804cd71 in attrs_build (attrs=0x8055670, attrs@entry=0x0, count_to_add=1,
    copy=copy@entry=true,
    generator=generator@entry=0x804b760 <vararg_generator>,
    state=state@entry=0xffffd544) at attrs.c:110
110                     if (!add || add->type == CKA_INVALID)
(gdb) bt
#0  0x0804cd71 in attrs_build (attrs=0x8055670, attrs@entry=0x0,
    count_to_add=1, copy=copy@entry=true,
    generator=generator@entry=0x804b760 <vararg_generator>,
    state=state@entry=0xffffd544) at attrs.c:110
#1  0x0804cf3f in p11_attrs_build (attrs=attrs@entry=0x0) at attrs.c:161
#2  0x0804af5d in test_build_one (tc=0x8055290) at test-attrs.c:71
#3  0x0804e940 in CuTestRun (tc=tc@entry=0x8055290) at cutest/CuTest.c:143
#4  0x0804ef3c in CuSuiteRun (testSuite=testSuite@entry=0x8054120)
    at cutest/CuTest.c:279
#5  0x08049023 in main () at test-attrs.c:605
(gdb)
--------------------------------------