Hi!
On 6/19/20 12:08 PM, John Paul Adrian Glaubitz wrote:
> This works, both with PERL_DEBUG_READONLY_OPS and without:
Updated patch attached.
Adrian
--
.''`. John Paul Adrian Glaubitz
: :' : Debian Developer - glaub...@debian.org
`. `' Freie Universitaet Berlin - glaub...@physik.fu-berlin.de
`- GPG: 62FF 8A75 84E0 2956 9546 0006 7426 3B37 F5B5 F913
>From 65bed710c6b990285d7feae63e8e9b8c6f8ab8ec Mon Sep 17 00:00:00 2001
From: John Paul Adrian Glaubitz <glaub...@physik.fu-berlin.de>
Date: Fri, 19 Jun 2020 12:30:57 +0200
Subject: [PATCH] op.h: Add additional padding to struct opslab to ensure
proper alignment
On m68k, the natural alignment is 16 bits which causes the opslab_opslot
member of "struct opslab" to be aligned at a 16-bit offset. Other 32-bit
and 64-bit architectures have a natural alignment of at least 32 bits, so
the offset is always guaranteed to be at least 32-bit-aligned.
Fix this by adding additional padding bytes before the opslab_opslot
member, both for cases when PERL_DEBUG_READONLY_OPS defined and not
defined to ensure the offset of oplab_slots is always 32-bit-aligned.
On architectures which have a natural alignment of at least 32 bits,
the padding does not affect the alignment, offsets or struct size.
---
op.h | 2 ++
1 file changed, 2 insertions(+)
diff --git a/op.h b/op.h
index fc21f03cda..b620983d38 100644
--- a/op.h
+++ b/op.h
@@ -713,7 +713,9 @@ struct opslab {
units) */
# ifdef PERL_DEBUG_READONLY_OPS
bool opslab_readonly;
+ U8 opslab_padding1[3]; /* padding to ensure that opslab_slots is always */
# endif
+ U16 opslab_padding2; /* located at an offset with 32-bit alignment */
OPSLOT opslab_slots; /* slots begin here */
};
--
2.27.0
