From: Eric Botcazou <ebotcazou@adacore.com>
Date: Fri, 23 Aug 2024 15:06:00 +0000 (+0200)
Subject: ada: Add kludge for quirk of ancient 32-bit ABIs to previous change
X-Git-Tag: basepoints/gcc-16~6146
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=a19cf635ea29658d5f9fc19199473d6d823ef2d1;p=thirdparty%2Fgcc.git

ada: Add kludge for quirk of ancient 32-bit ABIs to previous change

Some ancient 32-bit ABIs, most notably that of x86/Linux, misalign double
scalars in record types, so comparing DECL_ALIGN with TYPE_ALIGN directly
may give the wrong answer for them.

gcc/ada/

	* gcc-interface/trans.cc (addressable_p) <COMPONENT_REF>: Add kludge
	to cope with ancient 32-bit ABIs.
---

diff --git a/gcc/ada/gcc-interface/trans.cc b/gcc/ada/gcc-interface/trans.cc
index fadd6b483d5..c99b06670d5 100644
--- a/gcc/ada/gcc-interface/trans.cc
+++ b/gcc/ada/gcc-interface/trans.cc
@@ -10294,8 +10294,20 @@ addressable_p (tree gnu_expr, tree gnu_type)
 		   check the alignment of the containing record, as it is
 		   guaranteed to be not smaller than that of its most
 		   aligned field that is not a bit-field.  */
-		&& DECL_ALIGN (TREE_OPERAND (gnu_expr, 1))
-		   >= TYPE_ALIGN (TREE_TYPE (gnu_expr)))
+		&& (DECL_ALIGN (TREE_OPERAND (gnu_expr, 1))
+		    >= TYPE_ALIGN (TREE_TYPE (gnu_expr))
+#ifdef TARGET_ALIGN_DOUBLE
+		   /* Cope with the misalignment of doubles in records for
+		      ancient 32-bit ABIs like that of x86/Linux.  */
+		   || (DECL_ALIGN (TREE_OPERAND (gnu_expr, 1)) == 32
+		       && TYPE_ALIGN (TREE_TYPE (gnu_expr)) == 64
+		       && !TARGET_ALIGN_DOUBLE
+#ifdef TARGET_64BIT
+		       && !TARGET_64BIT
+#endif
+		      )
+#endif
+		       ))
 	       /* 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));