re PR c++/65736 (ICE (in process_init_constructor_array, at cp/typeck2.c:1263))

	PR c++/65736
	* constexpr.c (cxx_eval_pointer_plus_expression): Don't fold for VLAs,
	don't fold if op01 isn't divisible by TYPE_SIZE_UNIT.  Convert
	the expression to the original type at the end.

	* g++.dg/cpp0x/pr65736.C: New test.

From-SVN: r222022

5 files changed, 34 insertions, 8 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index d65662f..aa9349a 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -2,7 +2,7 @@
 
 	* doc/contrib.texi (Contributors): Add Maxim Kuvyrkov.
 
-2015-04-11 Jan Hubicka  <hubicka@ucw.cz>
+2015-04-11  Jan Hubicka  <hubicka@ucw.cz>
 
 	PR ipa/65743
 	* ipa-inline-transform.c (speculation_removed): Remove static var.
@@ -12,8 +12,8 @@
 	* ipa-prop.c (ipa_make_edge_direct_to_target): Do not
 	consider non-invariants.
 
-2015-04-11 Jan Hubicka  <hubicka@ucw.cz>
-	   Martin Liska  <mliska@suse.cz>
+2015-04-11  Jan Hubicka  <hubicka@ucw.cz>
+	    Martin Liska  <mliska@suse.cz>
 
 	PR ipa/65722
 	* ipa-icf.c (sem_item::compare_cgraph_references): function and
diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index 91ddee0..e5a6ae2 100644
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,3 +1,10 @@
+2015-04-12  Jakub Jelinek  <jakub@redhat.com>
+
+	PR c++/65736
+	* constexpr.c (cxx_eval_pointer_plus_expression): Don't fold for VLAs,
+	don't fold if op01 isn't divisible by TYPE_SIZE_UNIT.  Convert
+	the expression to the original type at the end.
+
 2015-04-09  Jakub Jelinek  <jakub@redhat.com>
 
 	PR c++/65690
diff --git a/gcc/cp/constexpr.c b/gcc/cp/constexpr.c
index f5be8df..2952cbe 100644
--- a/gcc/cp/constexpr.c
+++ b/gcc/cp/constexpr.c
@@ -2929,6 +2929,7 @@ cxx_eval_pointer_plus_expression (const constexpr_ctx *ctx, tree t,
 				  bool lval, bool *non_constant_p,
 				  bool *overflow_p)
 {
+  tree orig_type = TREE_TYPE (t);
   tree op00 = TREE_OPERAND (t, 0);
   tree op01 = TREE_OPERAND (t, 1);
   location_t loc = EXPR_LOCATION (t);
@@ -2945,7 +2946,9 @@ cxx_eval_pointer_plus_expression (const constexpr_ctx *ctx, tree t,
   /* &A[i] p+ j => &A[i + j] */
   if (TREE_CODE (op00) == ARRAY_REF
       && TREE_CODE (TREE_OPERAND (op00, 1)) == INTEGER_CST
-      && TREE_CODE (op01) == INTEGER_CST)
+      && TREE_CODE (op01) == INTEGER_CST
+      && TYPE_SIZE_UNIT (TREE_TYPE (op00))
+      && TREE_CODE (TYPE_SIZE_UNIT (TREE_TYPE (op00))) == INTEGER_CST)
     {
       tree type = TREE_TYPE (op00);
       t = fold_convert_loc (loc, ssizetype, TREE_OPERAND (op00, 1));
@@ -2953,15 +2956,21 @@ cxx_eval_pointer_plus_expression (const constexpr_ctx *ctx, tree t,
       /* Don't fold an out-of-bound access.  */
       if (!tree_int_cst_le (t, nelts))
 	return NULL_TREE;
+      op01 = cp_fold_convert (ssizetype, op01);
+      /* Don't fold if op01 can't be divided exactly by TYPE_SIZE_UNIT.
+	 constexpr int A[1]; ... (char *)&A[0] + 1 */
+      if (!integer_zerop (fold_build2_loc (loc, TRUNC_MOD_EXPR, sizetype,
+					   op01, TYPE_SIZE_UNIT (type))))
+	return NULL_TREE;
       /* Make sure to treat the second operand of POINTER_PLUS_EXPR
 	 as signed.  */
-      op01 = fold_build2_loc (loc, EXACT_DIV_EXPR, ssizetype,
-			      cp_fold_convert (ssizetype, op01),
+      op01 = fold_build2_loc (loc, EXACT_DIV_EXPR, ssizetype, op01,
 			      TYPE_SIZE_UNIT (type));
       t = size_binop_loc (loc, PLUS_EXPR, op01, t);
       t = build4_loc (loc, ARRAY_REF, type, TREE_OPERAND (op00, 0),
 		      t, NULL_TREE, NULL_TREE);
       t = cp_build_addr_expr (t, tf_warning_or_error);
+      t = cp_fold_convert (orig_type, t);
       return cxx_eval_constant_expression (ctx, t, lval, non_constant_p,
 					   overflow_p);
     }
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 401bf14..ea6b3a4 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,5 +1,10 @@
-2015-04-11 Jan Hubicka  <hubicka@ucw.cz>
-	   Martin Liska  <mliska@suse.cz>
+2015-04-12  Jakub Jelinek  <jakub@redhat.com>
+
+	PR c++/65736
+	* g++.dg/cpp0x/pr65736.C: New test.
+
+2015-04-11  Jan Hubicka  <hubicka@ucw.cz>
+	    Martin Liska  <mliska@suse.cz>
 
 	PR ipa/65722
 	* g++.dg/ipa/pr65722.C: New testcase.
diff --git a/gcc/testsuite/g++.dg/cpp0x/pr65736.C b/gcc/testsuite/g++.dg/cpp0x/pr65736.C
new file mode 100644
index 0000000..6e9c7fb
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp0x/pr65736.C
@@ -0,0 +1,5 @@
+// PR c++/65736
+// { dg-do compile { target c++11 } }
+
+int a[1];                                                                                                                                 
+char *b[1] { (char *)&a[0] + 1 };