This is output from `defines' version 4.1.1, from your buddies at Newtware!
Sun Apr 15 15:46:04 HKT 2012
BSD/OS bsd31.localdomain 3.1 BSDI BSD/OS 3.1 Kernel #4: Thu Oct 16 16:16:52 MDT 1997     polk@corp.BSDI.COM:/amd/demiurge/home/polk/sys-3.0patches/compile/GENERIC  i386
cc = [gcc]

__BASE_FILE__	= "/tmp/def9576.c"
__DATE__	= "Apr 15 2012"
__FILE__	= "/tmp/def9576.c"
__GNUC_MINOR__	= 7 
__GNUC__	= 2 
__IMMEDIATE_PREFIX__	= 
__INCLUDE_LEVEL__	= 0
__LINE__	= 6167
__PTRDIFF_TYPE__	= int
__REGISTER_PREFIX__	= 
__SIZE_TYPE__	= unsigned int
__STDC_VERSION__	= 199409L
__STDC__	= 1
__TIME__	= "15:46:06"
__USER_LABEL_PREFIX__	= 
__VERSION__	= "2.7.2.1"
__WCHAR_TYPE__	= int
__bsdi__	= 1 
__i386__	= 1 
bsdi	= 1 
i386	= 1 
unix	= 1 

Checking other possibilities; should already be listed above:
__DATE__	= "Apr 15 2012"
__FILE__	= "/tmp/def9576.c"
__GNUC__	= 2
__LINE__	= 25
__STDC__	= 1
__TIME__	= "15:46:06"

Sizes of basic variable types:
  sizeof(char)           = 8 bits
  sizeof(short)          = 16 bits
  sizeof(int)            = 32 bits
  sizeof(long)           = 32 bits
  sizeof(float)          = 32 bits
  sizeof(double)         = 64 bits
  sizeof(long double)    = 96 bits
  sizeof(char *)         = 32 bits
  sizeof(char (*)(char)) = 32 bits