re PR c++/50956 (-Wcast-qual does not work)

2011-11-02  Paolo Carlini  <paolo.carlini@oracle.com>

	PR c++/50956
	* builtins.c (fold_builtin_memchr): Fix cast.

/cp
2011-11-02  Paolo Carlini  <paolo.carlini@oracle.com>

	PR c++/50956
	* typeck.c (build_const_cast_1): Fix -Wcast-qual for false
	comp_ptr_ttypes_const.

/testsuite
2011-11-02  Paolo Carlini  <paolo.carlini@oracle.com>

	PR c++/50956
	* g++.dg/warn/Wcast-qual2.C: New.

From-SVN: r180786