Another preprocessor problem?

[utzoo!decvax!ucbvax!unix-wizards]

>From mccallum at UTEXAS-11 Tue Sep 29 09:56:22 1981
While we're on the subject of preprocessor (Version 7) problems, has anyone
come across and possibly solved a problem with unary operations for #if?
The following example shows the problem I've come across.

#define	TOKEN	-1

#if TOKEN==-1
This will fail (doesn't get copied)
#endif

#if TOKEN==-1
This will work (does get copied)
#endif

All comparisons after the first work.  The problem occurs independently for
each unique value (-1, -2, -3, etc).  All unary operations are affected.
This is a problem on our 11 system, but when I tried it on a Perkin-Elmer
system, it worked correctly.  Any ideas?

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