Don't optimize function if inference failed

This was respected only for the single-function optimizations, not
in func-info mode.

Author: nikic

ext/opcache/Optimizer/zend_optimizer.c

@@ -1488,8 +1488,11 @@ int zend_optimize_script(zend_script *script, zend_long optimization_level, zend
 		for (i = 0; i < call_graph.op_arrays_count; i++) {
 			func_info = ZEND_FUNC_INFO(call_graph.op_arrays[i]);
 			if (func_info) {
-				zend_dfa_analyze_op_array(call_graph.op_arrays[i], &ctx, &func_info->ssa);
-				func_info->flags = func_info->ssa.cfg.flags;
+				if (zend_dfa_analyze_op_array(call_graph.op_arrays[i], &ctx, &func_info->ssa) == SUCCESS) {
+					func_info->flags = func_info->ssa.cfg.flags;
+				} else {
+					ZEND_SET_FUNC_INFO(call_graph.op_arrays[i], NULL);
+				}
 			}
 		}