Segfault in 2.13.63

[John David Duncan]

Hi there,

I see the following crash in 2.13.63:

Finding the ideal number of pages...
Fitting music on 1 or 2 pages...
Drawing systems...
Program received signal EXC_BAD_ACCESS, Could not access memory.
Reason: KERN_PROTECTION_FAILURE at address: 0x00000000
0x00047e02 in Beam::print ()
(gdb) bt
#0  0x00047e02 in Beam::print ()
#1  0x0059a471 in scm_apply ()
#2  0x005a07ab in scm_call_1 ()
#3  0x000bf1a4 in Grob::try_callback_on_alist ()
#4  0x000bf397 in Grob::internal_get_property ()
 [...]

I can supply a substantial .ly file (about 8KB) that causes this crash, 
but I wouldn't know how to come up with a "tiny" example.

Any advice? 

Thanks,

JD