From: Cyril Hrubis <chrubis@suse.cz>
To: linux-api@vger.kernel.org
Cc: ltp@lists.linux.it, libc-alpha@sourceware.org
Subject: asm-generic/int-ll64.h wrongly used on x86_64?
Date: Fri, 19 Nov 2021 13:38:06 +0100 [thread overview]
Message-ID: <YZearmiVEw9/eor9@yuki> (raw)
Hi!
I was writing simple userspace code that prints the values from the
struct statx the line in question looks like:
printf("%" PRIu64 "\n", st.stx_size);
This unexpectedly gives me warning on x86_64:
warning: format '%lu' expects argument of type 'long unsigned int', but argument 5 has type '__u64' {aka 'long long unsigned int'}
Digging into the issue I've found that include/asm-generic/types.h looks like:
#ifndef _ASM_GENERIC_TYPES_H
#define _ASM_GENERIC_TYPES_H
/*
* int-ll64 is used everywhere now.
*/
#include <asm-generic/int-ll64.h>
#endif /* _ASM_GENERIC_TYPES_H */
Which is the cause why you cannot print __u64 with PRIu64 and would
force every userspace code to explicitly cast any __u64 in order to get
rid warnings. I would say that it would be better to fix the headers so
that __u64 has the same type as uint64_t so that PRIu64 could be then
used to print __u64 as well.
--
Cyril Hrubis
chrubis@suse.cz
WARNING: multiple messages have this Message-ID (diff)
From: Cyril Hrubis <chrubis@suse.cz>
To: linux-api@vger.kernel.org
Cc: libc-alpha@sourceware.org, ltp@lists.linux.it
Subject: [LTP] asm-generic/int-ll64.h wrongly used on x86_64?
Date: Fri, 19 Nov 2021 13:38:06 +0100 [thread overview]
Message-ID: <YZearmiVEw9/eor9@yuki> (raw)
Hi!
I was writing simple userspace code that prints the values from the
struct statx the line in question looks like:
printf("%" PRIu64 "\n", st.stx_size);
This unexpectedly gives me warning on x86_64:
warning: format '%lu' expects argument of type 'long unsigned int', but argument 5 has type '__u64' {aka 'long long unsigned int'}
Digging into the issue I've found that include/asm-generic/types.h looks like:
#ifndef _ASM_GENERIC_TYPES_H
#define _ASM_GENERIC_TYPES_H
/*
* int-ll64 is used everywhere now.
*/
#include <asm-generic/int-ll64.h>
#endif /* _ASM_GENERIC_TYPES_H */
Which is the cause why you cannot print __u64 with PRIu64 and would
force every userspace code to explicitly cast any __u64 in order to get
rid warnings. I would say that it would be better to fix the headers so
that __u64 has the same type as uint64_t so that PRIu64 could be then
used to print __u64 as well.
--
Cyril Hrubis
chrubis@suse.cz
--
Mailing list info: https://lists.linux.it/listinfo/ltp
next reply other threads:[~2021-11-19 12:37 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-11-19 12:38 Cyril Hrubis [this message]
2021-11-19 12:38 ` [LTP] asm-generic/int-ll64.h wrongly used on x86_64? Cyril Hrubis
2021-11-19 13:11 ` Florian Weimer
2021-11-19 13:11 ` [LTP] " Florian Weimer
2021-11-19 13:53 ` Cyril Hrubis
2021-11-19 13:53 ` [LTP] " Cyril Hrubis
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=YZearmiVEw9/eor9@yuki \
--to=chrubis@suse.cz \
--cc=libc-alpha@sourceware.org \
--cc=linux-api@vger.kernel.org \
--cc=ltp@lists.linux.it \
/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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.