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From: scjones@sdrc.UUCP (Larry Jones)
Newsgroups: comp.unix.microport
Subject: 386/3.0e bug in cc
Keywords: unsigned in constant expressions
Message-ID: <524@sdrc.UUCP>
Date: 2 Feb 89 22:28:05 GMT
Organization: Structural Dynamics Research Corp., Cincinnati
Lines: 19

I just ran across a bug in the c compiler on 386/3.0e.  If you
compare an unsigned constant expression to a signed constant
expression, the result of the comparison is computed at compile
time using a SIGNED comparison rather than an UNSIGNED comparison.

For example:

	~(unsigned)0 < 1000

is evaluated as 1 when it should clearly be 0.  If you stick in a
variable so that the compiler has to generate code, the code gets
the right answer.

----
Larry Jones                         UUCP: uunet!sdrc!scjones
SDRC                                      scjones@sdrc.UU.NET
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