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Date: Tue, 29 Nov 2005 06:14:00 -0000
Subject: [Bug c/25151]  New: GCC issues warnings to a syntactically correct expression.
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From: "mishabear at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
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Put the following code in a file tt.c and compile tt.c with command "gcc -Wall
tt.c", then the compiler will complain.

int main()
{
        void *pv;

        pv = (pv=0);
        return 0;
}

The compiler complains:
tt.c: In function `main':
tt.c:5: warning: operation on `pv' may be undefined

The result of "gcc --version" is:
gcc (GCC) 3.2.3 20030502 (Red Hat Linux 3.2.3-52)
Copyright (C) 2002 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

The result of "cat /etc/issue" is:
Red Hat Enterprise Linux AS release 3 (Taroon Update 5)
Kernel \r on an \m

The result of "uname -a" is:
Linux AS3-A64 2.4.21-32.EL #1 SMP Fri Apr 15 21:02:58 EDT 2005 x86_64 x86_64
x86_64 GNU/Linux

In fact the type of pv has no matter with the warning. The warning will still
show up if the type of pv is changed to int, short or double.


-- 
           Summary: GCC issues warnings to a syntactically correct
                    expression.
           Product: gcc
           Version: 3.2.3
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: mishabear at gmail dot com


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=25151