Re: size_t and int comparison

From: David Crocker (dcrocker_at_eschertech.ccoomm)
Date: 01/09/05 

Date: Sun, 9 Jan 2005 22:03:39 -0000

"tings" <tings668@hotmail.com> wrote in message
news:%RgEd.10483$c13.154@bgtnsc04-news.ops.worldnet.att.net...
> for (int i=0;i < strlen(pathcmd);i++){//this line cause a warning
>
> warning C4018: '<' : signed/unsigned mismatch
>
> strlen returns a number of type 'size_t'. size_t is an unsigned type and
> you are comparing it to an int, a signed type.
>
> Two solutions to remove the warning:
>
> 1. Change the type of the variable 'i' to 'size_t'.
> 2. staic_cast i to "unsigned" type.
>
> Which way is better in C++?
>
(2) is much better. Mixing up 'int' and 'size_t' is a sure way to write
non-portable code. For example, for most 64-bit C++ compilers, size_t is 64
bits whereas int is 32 bits. It's unlikely you would have a string longer
than 4Gb characters even on a 64-bit machine; but if you did, the code would
break.

David Crocker

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