diff options
Diffstat (limited to 'gcc/ada/gcc-interface/trans.c')
| -rw-r--r-- | gcc/ada/gcc-interface/trans.c | 30 |
1 files changed, 25 insertions, 5 deletions
diff --git a/gcc/ada/gcc-interface/trans.c b/gcc/ada/gcc-interface/trans.c index 077d4a6..53a277e 100644 --- a/gcc/ada/gcc-interface/trans.c +++ b/gcc/ada/gcc-interface/trans.c @@ -6869,10 +6869,14 @@ gnat_to_gnu (Node_Id gnat_node) N_Raise_Constraint_Error)); } - /* If our result has side-effects and is of an unconstrained type, - make a SAVE_EXPR so that we can be sure it will only be referenced - once. Note we must do this before any conversions. */ + /* If the result has side-effects and is of an unconstrained type, make a + SAVE_EXPR so that we can be sure it will only be referenced once. But + this is useless for a call to a function that returns an unconstrained + type with default discriminant, as we cannot compute the size of the + actual returned object. We must do this before any conversions. */ if (TREE_SIDE_EFFECTS (gnu_result) + && !(TREE_CODE (gnu_result) == CALL_EXPR + && TYPE_IS_PADDING_P (TREE_TYPE (gnu_result))) && (TREE_CODE (gnu_result_type) == UNCONSTRAINED_ARRAY_TYPE || CONTAINS_PLACEHOLDER_P (TYPE_SIZE (gnu_result_type)))) gnu_result = gnat_stabilize_reference (gnu_result, false, NULL); @@ -6898,7 +6902,11 @@ gnat_to_gnu (Node_Id gnat_node) 3. If the type is void or if we have no result, return error_mark_node to show we have no result. - 4. Finally, if the type of the result is already correct. */ + 4. If this a call to a function that returns an unconstrained type with + default discriminant, return the call expression unmodified since we + cannot compute the size of the actual returned object. + + 5. Finally, if the type of the result is already correct. */ if (Present (Parent (gnat_node)) && (lhs_or_actual_p (gnat_node) @@ -6949,7 +6957,19 @@ gnat_to_gnu (Node_Id gnat_node) else if (gnu_result == error_mark_node || gnu_result_type == void_type_node) gnu_result = error_mark_node; - else if (gnu_result_type != TREE_TYPE (gnu_result)) + else if (TREE_CODE (gnu_result) == CALL_EXPR + && TYPE_IS_PADDING_P (TREE_TYPE (gnu_result)) + && CONTAINS_PLACEHOLDER_P (TYPE_SIZE (gnu_result_type))) + { + /* ??? We need to convert if the padded type has fixed size because + gnat_types_compatible_p will say that padded types are compatible + but the gimplifier will not and, therefore, will ultimately choke + if there isn't a conversion added early. */ + if (TREE_CODE (TYPE_SIZE (TREE_TYPE (gnu_result))) == INTEGER_CST) + gnu_result = convert (gnu_result_type, gnu_result); + } + + else if (TREE_TYPE (gnu_result) != gnu_result_type) gnu_result = convert (gnu_result_type, gnu_result); /* We don't need any NOP_EXPR or NON_LVALUE_EXPR on the result. */ |