https://gcc.gnu.org/g:65186cab1d3c9b0dad17dc0536586bec634b93f3
commit r15-3473-g65186cab1d3c9b0dad17dc0536586bec634b93f3
Author: Eric Botcazou <ebotca...@adacore.com>
Date: Mon Aug 26 11:16:41 2024 +0200
ada: Add bypass for internal fields on strict-alignment platforms
This is required to support misalignment of tagged types in legacy code.
gcc/ada/
* gcc-interface/trans.cc (addressable_p) <COMPONENT_REF>: Add bypass
for internal fields on strict-alignment platforms.
Diff:
---
gcc/ada/gcc-interface/trans.cc | 11 ++++++++---
1 file changed, 8 insertions(+), 3 deletions(-)
diff --git a/gcc/ada/gcc-interface/trans.cc b/gcc/ada/gcc-interface/trans.cc
index 9e9f5f8dcba..92e000686fb 100644
--- a/gcc/ada/gcc-interface/trans.cc
+++ b/gcc/ada/gcc-interface/trans.cc
@@ -10295,9 +10295,14 @@ addressable_p (tree gnu_expr, tree gnu_type)
is guaranteed to be not smaller than that of its most
aligned field that is not a bit-field. However, we need
to cope with quirks of ABIs that may misalign fields. */
- && DECL_ALIGN (TREE_OPERAND (gnu_expr, 1))
- >= default_field_alignment (TREE_OPERAND (gnu_expr, 1),
- TREE_TYPE (gnu_expr)))
+ && (DECL_ALIGN (TREE_OPERAND (gnu_expr, 1))
+ >= default_field_alignment (TREE_OPERAND (gnu_expr, 1),
+ TREE_TYPE (gnu_expr))
+ /* We do not enforce this on strict-alignment platforms for
+ internal fields in order to keep supporting misalignment
+ of tagged types in legacy code. */
+ || (!STRICT_ALIGNMENT
+ && DECL_INTERNAL_P (TREE_OPERAND (gnu_expr, 1)))))
/* The field of a padding record is always addressable. */
|| TYPE_IS_PADDING_P (TREE_TYPE (TREE_OPERAND (gnu_expr, 0))))
&& addressable_p (TREE_OPERAND (gnu_expr, 0), NULL_TREE));
