diff --git a/gcc/ada/ChangeLog b/gcc/ada/ChangeLog
index 2b9eed4cbe9..3ffb45e7114 100644
--- a/gcc/ada/ChangeLog
+++ b/gcc/ada/ChangeLog
@@ -1,3 +1,8 @@
+2015-11-18  Eric Botcazou  <ebotcazou@adacore.com>
+
+	* gcc-interface/trans.c (fold_constant_decl_in_expr) <ARRAY_REF>: If
+	the index is not itself constant then bail out.
+
 2015-11-18  Ed Schonberg  <schonberg@adacore.com>
 
 	* sem_ch4.adb (Try_Container_Indexing): When constructing the
diff --git a/gcc/ada/gcc-interface/trans.c b/gcc/ada/gcc-interface/trans.c
index eeb2aaca5cf..0d100193baa 100644
--- a/gcc/ada/gcc-interface/trans.c
+++ b/gcc/ada/gcc-interface/trans.c
@@ -975,6 +975,9 @@ fold_constant_decl_in_expr (tree exp)
 
     case ARRAY_REF:
     case ARRAY_RANGE_REF:
+      /* If the index is not itself constant, then nothing can be folded.  */
+      if (!TREE_CONSTANT (TREE_OPERAND (exp, 1)))
+	return exp;
       op0 = fold_constant_decl_in_expr (TREE_OPERAND (exp, 0));
       if (op0 == TREE_OPERAND (exp, 0))
 	return exp;