extend.texi (C++ Attributes): Correct description of warn_unused type attribute.

	* doc/extend.texi (C++ Attributes): Correct description of
	warn_unused type attribute.

From-SVN: r233502

gcc/ChangeLog

+2016-02-17  Jonathan Wakely  <jwakely@redhat.com>
+
+	* doc/extend.texi (C++ Attributes): Correct description of
+	warn_unused type attribute.
+
 2016-02-17  Bill Schmidt  <wschmidt@linux.vnet.ibm.com>
 
 	* config/rs6000/altivec.md (*altivec_lvxl_<mode>_internal): Output

gcc/doc/extend.texi

@@ -20313,7 +20313,7 @@ types.
 
 This attribute is appropriate for types which just represent a value,
 such as @code{std::string}; it is not appropriate for types which
-control a resource, such as @code{std::mutex}.
+control a resource, such as @code{std::lock_guard}.
 
 This attribute is also accepted in C, but it is unnecessary because C
 does not have constructors or destructors.