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From: inouk@igt.net
To: gcc-gnats@gcc.gnu.org
Subject: c/4938: bad warnings about signed and unsigned
Date: Mon, 19 Nov 2001 21:29:00 -0000	[thread overview]
Message-ID: <20011124035237.4379.qmail@sourceware.cygnus.com> (raw)


>Number:         4938
>Category:       c
>Synopsis:       bad warnings about signed and unsigned
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    unassigned
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Fri Nov 23 19:56:00 PST 2001
>Closed-Date:
>Last-Modified:
>Originator:     inouk@igt.net
>Release:        unknown-1.0
>Organization:
>Environment:
Debian GNU/Linux GCC version 2.95 and 3.0
>Description:
The range of signed int is between -2147483648 and  2147483647

unsigned int between 0 and 4294967295

here a sample code:

      1 int main(void) {
      2
      3   unsigned int test;
      4   int test1;
      5
      6   test  = 4294967295;
      7   test  = 2147483648;
      8   test  = 2147483647;
      9
     10   test1 = 2147483647;
     11   test1 = -2147483648;
     12   test1 = -2147483647;
     13 }

I compile this and I have:
gcc t2.c
t2.c: In function `main':
t2.c:6: warning: decimal constant is so large that it is unsigned
t2.c:7: warning: decimal constant is so large that it is unsigned
t2.c:11: warning: decimal constant is so large that it is unsigned

I have a little difference with short, I never see warnings.

signed short: -32768 to 32767
unsigned short: 0 to 65535

sample code:
      1 int main(void) {
      2
      3   unsigned short test;
      4   short test1;
      5
      6   test  = 65535;
      7
      8   test1 = 65535;
      9   test1 = 32767;
     10 }

nothing about warning.  But, i "overflowed" test1 (in line 8).
>How-To-Repeat:
go to description
>Fix:
Better handling warnings :)
>Release-Note:
>Audit-Trail:
>Unformatted:


             reply	other threads:[~2001-11-24  3:56 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2001-11-19 21:29 inouk [this message]
2001-11-20  0:16 jsm28
2001-11-20  1:06 jsm28
2002-07-22 13:17 neil

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