re PR c/84873 (ICE: verify_ssa failed (error: definition in block 3 does not dominate use in block 4))

2018-03-16  Richard Biener  <rguenther@suse.de>

	PR c/84873
	* c-gimplify.c (c_gimplify_expr): Revert previous change.  Instead
	unshare the possibly folded expression.

From-SVN: r258591