re PR other/18555 (-isysroot is miss-documented)

        PR other/18555
        * doc/cppopts.texi (-isysroot): Document Darwin behaviour.

From-SVN: r164022

gcc/ChangeLog

+2010-09-08  Francois-Xavier Coudert  <fxcoudert@gcc.gnu.org>
+
+	PR other/18555
+	* doc/cppopts.texi (-isysroot): Document Darwin behaviour. 
+
 2010-09-08  Uros Bizjak  <ubizjak@gmail.com>
 
 	* config/i386/i386-protos.h (ix86_can_use_return_insn_p,

gcc/doc/cppopts.texi

@@ -492,7 +492,9 @@ would; @option{-iwithprefix} puts it where @option{-idirafter} would.
 @item -isysroot @var{dir}
 @opindex isysroot
 This option is like the @option{--sysroot} option, but applies only to
-header files.  See the @option{--sysroot} option for more information.
+header files (except for Darwin targets, where it applies to both header
+files and libraries).  See the @option{--sysroot} option for more
+information.
 
 @item -imultilib @var{dir}
 @opindex imultilib