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From: nero@eng.umd.edu (Oren L. Stern)
Newsgroups: comp.lang.c
Subject: Type of expression in switch statement
Message-ID: <1989Oct30.043155.1931@eng.umd.edu>
Date: 30 Oct 89 04:31:55 GMT
Sender: news@eng.umd.edu (The News System)
Reply-To: nero@eng.umd.edu (Oren L. Stern)
Organization: Merriversity of Uniland, College Purgatory
Lines: 24


   I've had a problem lately using the switch statement.  According to K&R
on page 202:

      The switch statement ... has the form
      
            switch (expression) statement
      
      The usual arithmetic conversion is performed on the expression, but the
      result must be int.

It turns out that where I meant to type "switch (node->tag)", I accidentally
typed "switch (node)".  Not so surprisingly, cc took it without complaint.
However, I went back and lint'ed it and lint took it without complaint as
well!  I am using the C compiler on a Sparcstation 1 running SunOS 4.0.3.
I have written other test programs and it seems both cc and lint allow pointers
as expressions in switch statements.  Is there something wrong with Sun's
compiler, or is there (gasp!) a mistake in K&R?

--
Oren Stern  |  nero@eng.umd.edu
Merriversity of Uniland, College Purgatory
-----
Disclaimer:  I speak only for myself and my evil twin brother, Otto.