Heap overflow checking fails on sparc

[Raymond Toy]

cmulisp -dynamic-space-size 32
* (defvar *1* (make-list 10000000))
*A2 gc_alloc_new_region failed, nbytes=8.
 CMUCL has run out of dynamic heap space (32 MB).
  You can control heap size with the -dynamic-space-size commandline option.
segv_handler: Real protection violation: 400, PC = 1bbcc
*A2 gc_alloc_new_region failed, nbytes=8.
 CMUCL has run out of dynamic heap space (32 MB).
  You can control heap size with the -dynamic-space-size commandline option.
Segmentation Fault (core dumped)

I'm pretty sure this used to work on sparc. The fault address of 0x1bbcc is in build_fake_control_stack_frame.