re PR middle-end/80823 (ICE: verify_flow_info failed)

gcc/
	PR middle-end/80823
	* tree-cfg.c (group_case_labels_stmt): Delete increment of "i";

gcc/testsuite/
	PR middle-end/80823
	* gcc.dg/pr80823.c: New test.

From-SVN: r248408

gcc/ChangeLog

+2017-05-24  Peter Bergner  <bergner@vnet.ibm.com>
+
+	PR middle-end/80823
+	* tree-cfg.c (group_case_labels_stmt): Delete increment of "i";
+
 2017-05-24  Andreas Krebbel  <krebbel@linux.vnet.ibm.com>
 
 	PR target/80725

gcc/testsuite/ChangeLog

+2017-05-24  Peter Bergner  <bergner@vnet.ibm.com>
+
+	PR middle-end/80823
+	* gcc.dg/pr80823.c: New test.
+
 2017-05-24  Andreas Krebbel  <krebbel@linux.vnet.ibm.com>
 
 	* gcc.target/s390/pr80725.c: New test.

gcc/testsuite/gcc.dg/pr80823.c

+/* PR middle-end/80823 ICE: verify_flow_info failed  */
+/* { dg-do compile }  */
+/* { dg-options "-O3" }  */
+
+int a, c;
+int b[1];
+static inline int
+fn1() {
+  switch (a)
+  case 0:
+  case 2:
+    return 1;
+  return 0;
+}
+void fn2() {
+  int i;
+  for (;; ++i) {
+    c = b[i];
+    int d = !fn1();
+    if (d)
+      __asm__("");
+  }
+}

gcc/tree-cfg.c

@@ -1726,7 +1726,6 @@ group_case_labels_stmt (gswitch *stmt)
 	    remove_edge_and_dominated_blocks (base_edge);
 	  gimple_switch_set_label (stmt, base_index, NULL_TREE);
 	  new_size--;
-	  i++;
 	}
     }