re PR c/60101 (Long compile times when mixed complex floating point datatypes are used in lengthy expressions)

	PR c/60101
	* c-common.c (merge_tlist): If copy is true, call new_tlist,
	if false, add ADD itself, rather than vice versa.
	(verify_tree): For COND_EXPR, don't call merge_tlist with non-zero
	copy.  For SAVE_EXPR, only call merge_tlist once.

	* c-c++-common/pr60101.c: New test.

From-SVN: r207711