re PR middle-end/83185 (ICE with -fsanitize=address in build_simple_mem_ref_loc, at tree.c:4696)

	PR middle-end/83185
	* tree.c (build_simple_mem_ref_loc): Handle
	get_addr_base_and_unit_offset returning a MEM_REF.

	* gcc.dg/asan/pr83185.c: New test.

From-SVN: r255229

gcc/ChangeLog

 2017-11-29  Jakub Jelinek  <jakub@redhat.com>
 
+	PR middle-end/83185
+	* tree.c (build_simple_mem_ref_loc): Handle
+	get_addr_base_and_unit_offset returning a MEM_REF.
+
 	PR middle-end/80929
 	* rtlanal.c (seq_cost): For non-single_set insns try to use insn_cost.
 

gcc/testsuite/ChangeLog

 2017-11-29  Jakub Jelinek  <jakub@redhat.com>
 
+	PR middle-end/83185
+	* gcc.dg/asan/pr83185.c: New test.
+
 	PR target/80819
 	* gcc.target/i386/pr80819-1.c: New test.
 	* gcc.target/i386/pr80819-2.c: New test.

gcc/testsuite/gcc.dg/asan/pr83185.c

+/* PR middle-end/83185 */
+/* { dg-do compile } */
+
+#include <stdarg.h>
+
+int bar (void);
+
+void
+foo (int i, ...)
+{
+  va_list aps[bar()];
+  va_start (aps[4], i);
+  va_end (aps[4]);
+}

gcc/tree.c

@@ -4692,7 +4692,13 @@ build_simple_mem_ref_loc (location_t loc, tree ptr)
     {
       ptr = get_addr_base_and_unit_offset (TREE_OPERAND (ptr, 0), &offset);
       gcc_assert (ptr);
-      ptr = build_fold_addr_expr (ptr);
+      if (TREE_CODE (ptr) == MEM_REF)
+	{
+	  offset += mem_ref_offset (ptr).to_short_addr ();
+	  ptr = TREE_OPERAND (ptr, 0);
+	}
+      else
+	ptr = build_fold_addr_expr (ptr);
       gcc_assert (is_gimple_reg (ptr) || is_gimple_min_invariant (ptr));
     }
   tem = build2 (MEM_REF, TREE_TYPE (ptype),