Are you able to run all of the libMesh examples (automake branch) with GNU GCC on your mac?  I've been chatting with Paul and he mentioned that misc_ex6 seg faults (which we have confirmed here), but we are also seeing a similar problem with adjoints_ex1.  These problems aren't unique to the automake branch, but Paul mentioned that it was working there, just not in trunk.  I'm seeing the problem consistently in both branches.  Unfortunately, we get bad stack traces when we try to debug.  Something about a misaligned stack!  

None of these issues show up with "--disable-shared" but then again, our whole move to these new compilers was motivated by breakage in the Apple compilers (4.2.1) with dynamic casts to begin with that only manifested themselves when using shared libraries.  John and David have joined in now with their own independent builds of GCC and we are all independently seeing these issues in the libMesh examples.

Bottom Line:  I'm curious, does anyone have a completely working compiler that runs all examples in optimized and debug mode on OS X?

Interestingly, I didn't see this issue until recently because I've been running the MOOSE and application test suite which passed all 400+ tests in optimized mode without issues.  I finally run into an issue with an one of our examples in debug mode that looked an awful lot like the failures we are seeing in the libMesh examples mentioned above.

The saga continues,

On Mon, Oct 29, 2012 at 10:53 AM, Kirk, Benjamin (JSC-EG311) <> wrote:
> Ben,  I just manually added those flags on my system and it's working fine, both the devel and release versions.  I have GCC 4.6 but I'd be surprised if the issue was with 4.7 only.  What error are you seeing?

thanks - it is 4.7 only, believe it or not…

I can recreate the issue with their distributed package simply by adding -std=c++0x and using gcc-4.7, so I'll take it up with the developers.

It can't parse one of the compressed headers, which is less than useful…

make[4]: Nothing to be done for `all-am'.
  CXX    libfparser_la-fparser.lo
In file included from
extrasrc/ In function ‘unsigned int {anonymous}::readIdentifierCommon(const char*)’:
extrasrc/ error: unable to find character literal operator ‘operator"" l5’ with ‘char’ argument
extrasrc/ error: expected ‘)’ before numeric constant
extrasrc/ error: expected primary-expression before ‘]’ token
extrasrc/ error: expected ‘;’ before ‘]’ token
extrasrc/ error: unable to find character literal operator ‘operator"" lB’ with ‘char’ argument