PKGNG: SHLIBS causes pkg segfault on some ports

[Kimmo Paasiala]

I have the SHLIBS feature turned on in /usr/local/etc/pkg.conf and I'm
getting segfaults in the final stage of installation with some ports.

Here is the tail end of a log from building databases/db42 with SHLIBS on:

http://pastebin.com/3AqMdptc

Backtrace from gdb:

http://pastebin.com/V3QY1Mmm

What seems to be common for ports that cause pkg to segfault is that
they have at least some C++ code in them. Another thing in common is
that the backtrace always shows "libm.so.5" in test_depends () before
dlopen () and the _rtld_get_stack_prot () frames.

Operating system is FreeBDS 9-STABLE r237674 amd64. I have the whole
system compiled with CLANG including ports, /usr/bin/cc is CLANG.

I'm not seeing the same problem on 9.0-RELEASE powerpc with the system
and ports compiled with the stock gcc if that helps.

Regards,
Kimmo Paasiala