re PR debug/46561 (-fcompare-debug failure (length) with -O2 -ftree-vectorize -ftree-parallelize-loops)

	PR debug/46561
	* tree-parloops.c (try_create_redunction_list): Ignore debug stmts
	when looking for immediate uses.

	* gcc.dg/autopar/pr46561.c: New test.

From-SVN: r166975