re PR c++/17041 (Erroneous "suggest parentheses around assignment used as truth value" warning in template members.)

	PR c++/17041
	* pt.c (tsubst_copy, tsubst_copy_and_build): Copy TREE_NO_WARNING
	from input for MODOP_EXPR.

testsuite:
	* g++.dg/Wparentheses-3.C: New test.

From-SVN: r86241