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[PATCH] Fix bitfields with TYPE_USER_ALIGN base type
- From: Jakub Jelinek <jakub at redhat dot com>
- To: rth at redhat dot com, mark at codesourcery dot com
- Cc: gcc-patches at gcc dot gnu dot org
- Date: Wed, 7 Aug 2002 23:11:08 +0200
- Subject: [PATCH] Fix bitfields with TYPE_USER_ALIGN base type
- Reply-to: Jakub Jelinek <jakub at redhat dot com>
Hi!
This patch should fix the bitfields on __attribute__((aligned (...)))
typedefs. Bootstrapped on i386-redhat-linux, regression testing still
pending.
2002-08-07 Jakub Jelinek <jakub@redhat.com>
* stor-layout.c (place_union_field): For bitfields if
PCC_BITFIELD_TYPE_MATTERS and TYPE_USER_ALIGN, set record's
TYPE_USER_ALIGN.
* gcc.dg/bitfld-3.c: New test.
--- gcc/stor-layout.c.jj 2002-08-07 18:26:46.000000000 +0200
+++ gcc/stor-layout.c 2002-08-07 21:47:15.000000000 +0200
@@ -692,6 +692,7 @@ place_union_field (rli, field)
#endif
rli->record_align = MAX (rli->record_align, type_align);
rli->unpadded_align = MAX (rli->unpadded_align, type_align);
+ TYPE_USER_ALIGN (rli->t) |= TYPE_USER_ALIGN (TREE_TYPE (field));
}
#endif
@@ -847,6 +848,7 @@ place_field (rli, field)
rli->unpadded_align = MAX (rli->unpadded_align, DECL_ALIGN (field));
if (warn_packed)
rli->unpacked_align = MAX (rli->unpacked_align, TYPE_ALIGN (type));
+ user_align |= TYPE_USER_ALIGN (type);
}
}
else
@@ -939,6 +941,8 @@ place_field (rli, field)
- (offset * BITS_PER_UNIT + bit_offset) / type_align)
> tree_low_cst (TYPE_SIZE (type), 1) / type_align)
rli->bitpos = round_up (rli->bitpos, type_align);
+
+ user_align |= TYPE_USER_ALIGN (type);
}
#endif
@@ -980,6 +984,8 @@ place_field (rli, field)
!= ((offset * BITS_PER_UNIT + bit_offset + field_size - 1)
/ type_align))
rli->bitpos = round_up (rli->bitpos, type_align);
+
+ user_align |= TYPE_USER_ALIGN (type);
}
#endif
--- gcc/testsuite/gcc.dg/bitfld-3.c.jj 2002-08-07 21:55:08.000000000 +0200
+++ gcc/testsuite/gcc.dg/bitfld-3.c 2002-08-07 21:52:19.000000000 +0200
@@ -0,0 +1,67 @@
+/* Test for bitfield alignment in structs and unions. */
+/* { dg-do run } */
+/* { dg-options "-O2" } */
+
+extern void abort (void);
+extern void exit (int);
+
+typedef long la __attribute__((aligned (8)));
+
+struct A
+{
+ char a;
+ union UA
+ {
+ char x;
+ la y : 6;
+ } b;
+ char c;
+} a;
+
+struct B
+{
+ char a;
+ union UB
+ {
+ char x;
+ long y : 6 __attribute__((aligned (8)));
+ } b;
+ char c;
+} b;
+
+struct C
+{
+ char a;
+ struct UC
+ {
+ la y : 6;
+ } b;
+ char c;
+} c;
+
+struct D
+{
+ char a;
+ struct UD
+ {
+ long y : 6 __attribute__((aligned (8)));
+ } b;
+ char c;
+} d;
+
+int main (void)
+{
+ if (sizeof (a) != sizeof (b))
+ abort ();
+ if (sizeof (a) != sizeof (c))
+ abort ();
+ if (sizeof (a) != sizeof (d))
+ abort ();
+ if ((&a.c - &a.a) != (&b.c - &b.a))
+ abort ();
+ if ((&a.c - &a.a) != (&c.c - &c.a))
+ abort ();
+ if ((&a.c - &a.a) != (&d.c - &d.a))
+ abort ();
+ exit (0);
+}
Jakub