Help with building gcc

[Michael A. Pagels]

Can someone explain how to get rid of the following error while building gcc for the IRIS 4D:

cc -c -g   -I. -I../gcc-1.37.1 -I../gcc-1.37.1/config ../gcc-1.37.1/symout.c
ccom: Error: ../gcc-1.37.1/stddef.h, line 12: illegal type combination
      typedef unsigned long size_t;
      ----------------------------^
*** Error code 1

Stop.

I've seen this problem with "typedef unsigned long thing" in a number of forms with other pieces of code.  What's the general problem?

Thanks in advance.

Michael Pagels