[ Sorry ... I accidentally deleted the mail Peter sent, but I'll try to
  provide the context anyhow... ]

Re. Peter's statement that the following is confusing:

lestat (thorpej) ~ 1924% cpp -dM < /dev/null
#define __GCC_NEW_VARARGS__ 1
#define __NetBSD__ 1
#define sparc 1
#define __GNUC__ 1
#define __sparc__ 1
#define unix 1
lestat (thorpej) ~ 1925% 

Here's a snippet from /usr/bin/cpp:

[ . . . ]
#
#       @(#)usr.bin.cpp.sh      6.5 (Berkeley) 4/1/91
#
# Transitional front end to CCCP to make it behave like (Reiser) CCP:
#       specifies -traditional
#       doesn't search gcc-include
#
[ . . . ]
ALST="-traditional -D__GNUC__ -$ "
[ . . . ]

The "-traditional" turns off the __STDC___.

--------------------------------------------------------------------------
Jason R. Thorpe                                       thorpej@nas.nasa.gov
NASA Ames Research Center                               Home: 408.866.1912
NAS: M/S 258-6                                          Work: 415.604.0935
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