From: John David Anglin <dave@parisc-linux.org>
To: libc-alpha@sourceware.org
Cc: deller@gmx.de
Subject: [committed] hppa: Drop 16-byte pthread lock alignment
Date: Sun, 26 Mar 2023 21:22:11 +0000 [thread overview]
Message-ID: <ZCC3g2nKEtpz36nR@mx3210.localdomain> (raw)
[-- Attachment #1: Type: text/plain, Size: 2128 bytes --]
hppa: Drop 16-byte pthread lock alignment
Linux threads were removed about 12 years ago and the current
nptl implementation only requires 4-byte alignment for pthread
locks.
The 16-byte alignment causes various issues. For example in
building ignition-msgs, we have:
/usr/include/google/protobuf/map.h:124:37: error: static assertion failed
124 | static_assert(alignof(value_type) <= 8, "");
| ~~~~~~~~~~~~~~~~~~~~^~~~
This is caused by the 16-byte pthread lock alignment.
Signed-off-by: John David Anglin <dave.anglin@bell.net>
---
diff --git a/sysdeps/hppa/nptl/bits/pthreadtypes-arch.h b/sysdeps/hppa/nptl/bits/pthreadtypes-arch.h
index 999195c5b0..c1a46d66d0 100644
--- a/sysdeps/hppa/nptl/bits/pthreadtypes-arch.h
+++ b/sysdeps/hppa/nptl/bits/pthreadtypes-arch.h
@@ -40,7 +40,7 @@
#define __SIZEOF_PTHREAD_RWLOCK_T 64
#define __SIZEOF_PTHREAD_RWLOCKATTR_T 8
-#define __LOCK_ALIGNMENT __attribute__ ((__aligned__(16)))
+#define __LOCK_ALIGNMENT
#define __ONCE_ALIGNMENT
#endif /* bits/pthreadtypes.h */
diff --git a/sysdeps/hppa/nptl/bits/struct_rwlock.h b/sysdeps/hppa/nptl/bits/struct_rwlock.h
index e83b4aab52..59bc9fe76f 100644
--- a/sysdeps/hppa/nptl/bits/struct_rwlock.h
+++ b/sysdeps/hppa/nptl/bits/struct_rwlock.h
@@ -25,8 +25,14 @@ struct __pthread_rwlock_arch_t
/* In the old Linuxthreads pthread_rwlock_t, this is the
start of the 4-word 16-byte aligned lock structure. The
next four words are all set to 1 by the Linuxthreads
- PTHREAD_RWLOCK_INITIALIZER. We ignore them in NPTL. */
- int __compat_padding[4] __attribute__ ((__aligned__(16)));
+ PTHREAD_RWLOCK_INITIALIZER. We ignore them in NPTL.
+
+ The 16-byte aligned lock stucture causes various pthread
+ structures to be over aligned. This causes some builds
+ to fail which assume a maximum alignment of 8 bytes.
+ Linuxthreads has been removed for 12 years, so drop
+ alignment of lock structure. */
+ int __compat_padding[4];
unsigned int __readers;
unsigned int __writers;
unsigned int __wrphase_futex;
[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 833 bytes --]
next reply other threads:[~2023-03-26 21:22 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-03-26 21:22 John David Anglin [this message]
2023-03-27 0:33 ` Florian Weimer
2023-03-27 0:37 ` Sam James
2023-03-27 1:58 ` John David Anglin
2023-03-27 12:42 ` Florian Weimer
2023-03-30 21:08 ` John David Anglin
2023-03-31 7:14 ` Florian Weimer
2023-03-27 0:35 ` Sam James
2023-03-27 15:24 ` Pedro Alves
2023-07-06 16:01 ` John David Anglin
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=ZCC3g2nKEtpz36nR@mx3210.localdomain \
--to=dave@parisc-linux.org \
--cc=deller@gmx.de \
--cc=libc-alpha@sourceware.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).