Why am I seeing these warnings from system header files?

1 msg	Re: Why do I get: cannot declare variable 'sc' ...
2 msg	Why do I get: cannot declare variable ‘sc’ to b...
6 msg	Compiler options for PowerPC
2 msg	How to change CR/LF to LF when compile gcc-4.1....
4 msg	operator new[] and operator delete[]

Why am I seeing these warnings from system head...
\ Kevin Regan (30 Jul 2007)

3 msg	-Bgroup?
3 msg	GCC-3.3.6 and MIPS instruction 'EHB'
3 msg	cr5-6 registers on i386
1 msg	Re: WELCOME to gcc
25 msg	Robust detection of endianness at compile time.
1 msg	MESAJINIZ VAR
3 msg	configure warning - test: too many arguments
1 msg	Problem in loading DLL
3 msg	right shift : strange behavior
2 msg	TDF_DETAILS
6 msg	Initialization of a static member of a template...
1 msg	Re: dlopen() crash -gcc 3.4.6 20060404
1 msg	Rebuild GCC 4.2
3 msg	Unrolling loops

Subject:	Why am I seeing these warnings from system header files?
Group:	Gcc-help
From:	Kevin Regan
Date:	30 Jul 2007

I'm seeing the following:

g++ -c -W -Wall -Werror -Wpointer-arith -Wreturn-type -Wswitch -Wunused
-g -DUNIX -fPIC -I/home/scherf/v9/fullsail/f5app/f5em/include -isystem
/home/scherf/v9/fullsail/devfs/usr/include -isystem
/home/scherf/v9/fullsail/devfs/usr/include/iControlClient -isystem
/home/scherf/v9/fullsail/devfs/usr/include/mysql -isystem
/home/scherf/v9/fullsail/devfs/usr/include/mysql++ -isystem
/home/scherf/v9/fullsail/devfs/usr/include/easysoap ExampleFunctions.cpp
-o ExampleFunctions.o
cc1plus: warnings being treated as errors
/usr/include/c++/3.2.3/i386-redhat-linux/bits/codecvt_specializations.h:
84: warning: unused
parameter `int __ibom'
/usr/include/c++/3.2.3/i386-redhat-linux/bits/codecvt_specializations.h:
84: warning: unused
parameter `int __ebom'
...

Why are these warnings being generated when I'm not using
"-Wsystem-headers"?

Here is my system information:

% uname -a
Linux zim.pdsea.f5net.com 2.4.21-47.ELsmp #1 SMP Tue Aug 1 09:06:57 EDT
2006 i686 athlon i386 GNU/Linux

% g++ --version
g++ (GCC) 3.2.3 20030502 (Red Hat Linux 3.2.3-56)
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.

I am *not* seeing this behavior on another of my machines (this machine
has 3.2.3-52 rather than 3.2.3-56):

% uname -a
Linux regan95.pdsea.f5net.com 2.4.21-32.ELsmp #1 SMP Wed May 18 17:49:28
EDT 2005 i686 i686 i386 GNU/Linux

% $ g++ --version
g++ (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.

Thanks for any help,
Kevin Regan