[COMMITTED 25/31] ada: Fix crash with aliased array and if expression

["Marc Poulhiès" <poulhies@adacore.com>]

From: Ronan Desplanques <desplanques@adacore.com>

The way if expressions were translated led the gimplifying phase
to attempt to create a temporary of a variable-sized type in some
cases. This patch fixes this by adding an address indirection layer
in those cases.

gcc/ada/

	* gcc-interface/utils2.cc (build_cond_expr): Also apply an
	indirection when the result type is variable-sized.

Tested on x86_64-pc-linux-gnu, committed on master.

---
 gcc/ada/gcc-interface/utils2.cc | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/gcc/ada/gcc-interface/utils2.cc b/gcc/ada/gcc-interface/utils2.cc
index 64712cb9962..161f0f11e5c 100644
--- a/gcc/ada/gcc-interface/utils2.cc
+++ b/gcc/ada/gcc-interface/utils2.cc
@@ -1711,11 +1711,13 @@ build_cond_expr (tree result_type, tree condition_operand,
   true_operand = convert (result_type, true_operand);
   false_operand = convert (result_type, false_operand);
 
-  /* If the result type is unconstrained, take the address of the operands and
-     then dereference the result.  Likewise if the result type is passed by
-     reference, because creating a temporary of this type is not allowed.  */
+  /* If the result type is unconstrained or variable-sized, take the address
+     of the operands and then dereference the result.  Likewise if the result
+     type is passed by reference, because creating a temporary of this type is
+     not allowed.  */
   if (TREE_CODE (result_type) == UNCONSTRAINED_ARRAY_TYPE
       || type_contains_placeholder_p (result_type)
+      || !TREE_CONSTANT (TYPE_SIZE (result_type))
       || TYPE_IS_BY_REFERENCE_P (result_type))
     {
       result_type = build_pointer_type (result_type);
-- 
2.43.2