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Re: no warning for assigning unsigned int to plain int

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On Wed, 12 Oct 2011 07:36:00 -0700, V.Subramanian, India wrote:

> Consider the following program no_warning.c :
> 
> #include <stdlib.h>
> #include <stdio.h>
> 
> int main()
> {
>         size_t length = 4294967295U;
>         int size = 4294967295U;
> 
>         size = length;
> 
>         return EXIT_SUCCESS;
> }
> 
> When I compile this program with
> gcc (GCC) 3.4.3 20050227 (Red Hat 3.4.3-22.1) as
>      gcc -std=c99 -pedantic -Wall -Wextra no_warning.c
> it did not generate any warning.
> 
> Consider the statements:
> 
>         int size = 4294967295U;
> 
>         size = length;
> 
> In both these statements, I am assigning 'unsigned int' to 'plain int'.
> Still the compiler accepts them without issuing any warnings. I am
> unable to understand this.
> 
> Please explain.

It should not generate a warning. You invoke an implicit cast from size_t to
int. This is perfectly acceptable according to the C standard. One of the
regulars will undoubtedly provide chapter and verse...

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no warning for assigning unsigned int to plain int "V.Subramanian, India" <subramanian100in@yahoo.com> - 2011-10-12 07:36 -0700
  Re: no warning for assigning unsigned int to plain int James Kuyper <jameskuyper@verizon.net> - 2011-10-12 12:17 -0400
  Re: no warning for assigning unsigned int to plain int Kleuskes & Moos <kleuske@somewhere.else.net> - 2011-10-12 17:28 +0000
    Re: no warning for assigning unsigned int to plain int Keith Thompson <kst-u@mib.org> - 2011-10-12 12:36 -0700
  Re: no warning for assigning unsigned int to plain int Ike Naar <ike@sverige.freeshell.org> - 2011-10-12 17:53 +0000
  Re: no warning for assigning unsigned int to plain int Keith Thompson <kst-u@mib.org> - 2011-10-12 12:41 -0700

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