libstdc++/2923: signed/unsigned comparison in stringbuf::sync()

[jakob@unthought.net]

>Number:         2923
>Category:       libstdc++
>Synopsis:       signed/unsigned comparison in stringbuf::sync()
>Confidential:   no
>Severity:       non-critical
>Priority:       medium
>Responsible:    unassigned
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Thu May 24 03:56:01 PDT 2001
>Closed-Date:
>Last-Modified:
>Originator:     jakob@unthought.net
>Release:        gcc-2.96(RH), release -81 and others
>Organization:
>Environment:
i686, GNU/Linux
>Description:
I get the warning:
/usr/include/g++-3/sstream: In method `int stringbuf::sync ()':
/usr/include/g++-3/sstream:171: warning: comparison between signed and unsigned integer expressions

Obviously this isn't critical, everything works, it's just annoying.
>How-To-Repeat:
Compile the following file with g++ -Wall:
#include <sstream>

Yes, the only line required is the include of sstream.
>Fix:

buf.size() - rpos (in sstream:171) evaluates to a signed integer. It's compared with n of type streamsize.  I guess casting to signed or unsigned would fix this without any impact on any practical uses of the code.
>Release-Note:
>Audit-Trail:
>Unformatted:
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