XEmacs fails to build on Mac OS X 10.7 with a segfault.  The same
behaviour is manifest with the stock Apple compiler
(i686-apple-darwin11-llvm-gcc-4.2) and FSF GCC (4.6.1), with both the
old and the new GC (though the place of the error is different), and
other features enabled or not.  I am attempting to build the 21.5 branch
but the same happened with the 21.4 branch as well.  Here is the failure:

Dumping under the name xemacs
./xemacs -no-packages -batch -no-autoloads -l update-elc-2.el -f
batch-update-elc-2
/opt/sw/src/fink.build/xemacs-21.5.31-1/xemacs-21.5.31/src/../lisp
make[1]: *** [update-elc-2] Segmentation fault: 11
make: *** [src] Error 2

Running the same under GDB yields:

   Program received signal EXC_BAD_ACCESS, Could not access memory.
   Reason: KERN_INVALID_ADDRESS at address: 0x0000000106ede890
   0x00000001000bf4ba in pdump_load_finish () at dumper.c:2336
   2336	      (* ptr.address) = ptr.value + delta;

(old GC) and:

   Program received signal EXC_BAD_ACCESS, Could not access memory.
   Reason: KERN_INVALID_ADDRESS at address: 0x00000001097aa460
   0x00000001000eba6a in pdump_reloc_one_mc (data=0x100b01000,
desc=0x1097aa460) at dumper.c:1293
   1293	  for (pos = 0; desc[pos].type != XD_END; pos++)

(new GC).  Not sure what other information to include but I will be
monitoring the report and provide any extra stuff that might be needed.