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[Ada] Fix run-time segfault with private access-to-subprogram type
- From: Eric Botcazou <ebotcazou at adacore dot com>
- To: gcc-patches at gcc dot gnu dot org
- Date: Mon, 23 Sep 2019 10:10:18 +0200
- Subject: [Ada] Fix run-time segfault with private access-to-subprogram type
This fixes a segfault at run time in a very peculiar case where an access-to-
subprogram type is declared as private and used to pass the address of a local
subprogram and dereference it using different views of the type.
Tested on x86_64-suse-linux, applied on all active branches.
2019-09-23 Eric Botcazou <ebotcazou@adacore.com>
* gcc-interface/trans.c (Attribute_to_gnu): Test Can_Use_Internal_Rep
on the underlying type of the node.
(Call_to_gnu): Likewise with the type of the prefix.
--
Eric Botcazou
Index: gcc-interface/trans.c
===================================================================
--- gcc-interface/trans.c (revision 275988)
+++ gcc-interface/trans.c (working copy)
@@ -2254,32 +2254,29 @@ Attribute_to_gnu (Node_Id gnat_node, tre
/* For other address attributes applied to a nested function,
find an inner ADDR_EXPR and annotate it so that we can issue
a useful warning with -Wtrampolines. */
- else if (FUNC_OR_METHOD_TYPE_P (TREE_TYPE (gnu_prefix)))
- {
- gnu_expr = remove_conversions (gnu_result, false);
-
- if (TREE_CODE (gnu_expr) == ADDR_EXPR
- && decl_function_context (TREE_OPERAND (gnu_expr, 0)))
- {
- set_expr_location_from_node (gnu_expr, gnat_node);
-
- /* Also check the inlining status. */
- check_inlining_for_nested_subprog (TREE_OPERAND (gnu_expr, 0));
-
- /* Moreover, for 'Access or 'Unrestricted_Access with non-
- foreign-compatible representation, mark the ADDR_EXPR so
- that we can build a descriptor instead of a trampoline. */
- if ((attribute == Attr_Access
- || attribute == Attr_Unrestricted_Access)
- && targetm.calls.custom_function_descriptors > 0
- && Can_Use_Internal_Rep (Etype (gnat_node)))
- FUNC_ADDR_BY_DESCRIPTOR (gnu_expr) = 1;
-
- /* Otherwise, we need to check that we are not violating the
- No_Implicit_Dynamic_Code restriction. */
- else if (targetm.calls.custom_function_descriptors != 0)
- Check_Implicit_Dynamic_Code_Allowed (gnat_node);
- }
+ else if (FUNC_OR_METHOD_TYPE_P (TREE_TYPE (gnu_prefix))
+ && (gnu_expr = remove_conversions (gnu_result, false))
+ && TREE_CODE (gnu_expr) == ADDR_EXPR
+ && decl_function_context (TREE_OPERAND (gnu_expr, 0)))
+ {
+ set_expr_location_from_node (gnu_expr, gnat_node);
+
+ /* Also check the inlining status. */
+ check_inlining_for_nested_subprog (TREE_OPERAND (gnu_expr, 0));
+
+ /* Moreover, for 'Access or 'Unrestricted_Access with non-
+ foreign-compatible representation, mark the ADDR_EXPR so
+ that we can build a descriptor instead of a trampoline. */
+ if ((attribute == Attr_Access
+ || attribute == Attr_Unrestricted_Access)
+ && targetm.calls.custom_function_descriptors > 0
+ && Can_Use_Internal_Rep (Underlying_Type (Etype (gnat_node))))
+ FUNC_ADDR_BY_DESCRIPTOR (gnu_expr) = 1;
+
+ /* Otherwise, we need to check that we are not violating the
+ No_Implicit_Dynamic_Code restriction. */
+ else if (targetm.calls.custom_function_descriptors != 0)
+ Check_Implicit_Dynamic_Code_Allowed (gnat_node);
}
break;
@@ -5111,7 +5108,8 @@ Call_to_gnu (Node_Id gnat_node, tree *gn
/* If the access type doesn't require foreign-compatible representation,
be prepared for descriptors. */
if (targetm.calls.custom_function_descriptors > 0
- && Can_Use_Internal_Rep (Etype (Prefix (Name (gnat_node)))))
+ && Can_Use_Internal_Rep
+ (Underlying_Type (Etype (Prefix (Name (gnat_node))))))
by_descriptor = true;
}
else if (Nkind (Name (gnat_node)) == N_Attribute_Reference)