test derefnull fails on OS X

[gwright]

On OS X, the derefnull test fails because the test driver expects an exit code of 138 (SIGBUS) but the program exits with 139 (SIGSEGV). This is probably some relic of the early days of OS X, when access to pagezero gave a bus error instead of a segfault.

The behavior is now consistent with linux. The attached patch changes all.T to reflect this.

With this change, running the derefnull test gives:

OVERALL SUMMARY for test run started at Thu Mar 24 16:34:38 EDT 2011
    2710 total tests, which gave rise to
   10140 test cases, of which
       0 caused framework failures
   10133 were skipped

       7 expected passes
       0 expected failures
       0 unexpected passes
       0 unexpected failures

[igloo]

Thanks, I'll check what happens on my Mac.

[igloo]

Turns out it behaves differently on x86_64 and x86; fixed by:

Fri Mar 25 15:26:41 PDT 2011  Ian Lynagh <igloo@earth.li>
  * Correct expected exit code on OS X 64; fixes #5046