re PR c++/44628 (ICE in cp_build_unary_op at cp/typeck.c:4671)

/cp
2010-06-30  Paolo Carlini  <paolo.carlini@oracle.com>

	PR c++/44628
	* typeck.c (cp_build_unary_op): Early return error_mark_node when
	arg is NULL_TREE too.
	* call.c (convert_class_to_reference): Return error_mark_node when
	expr is NULL_TREE.

/testsuite
2010-06-30  Paolo Carlini  <paolo.carlini@oracle.com>

	PR c++/44628
	* g++.dg/template/crash100.C: New.

From-SVN: r161639