re PR tree-optimization/51396 (ICE: verify_flow_info failed: BB 4 can not throw but has an EH edge with -O2 -fnon-call-exceptions -mfma4)

	PR tree-optimization/51396
	* tree-ssa-math-opts.c (convert_mult_to_fma): Don't optimize
	if MUL_RESULT has zero uses.

	* g++.dg/opt/pr51396.C: New test.

From-SVN: r182028