From: Adhemerval Zanella <adhemerval.zanella@linaro.org>
To: Fangrui Song <maskray@google.com>
Cc: libc-alpha@sourceware.org
Subject: Re: [PATCH v2 2/4] stdio: Remove the usage of $(fno-unit-at-a-time) for errlist.c
Date: Thu, 12 May 2022 17:03:23 -0300 [thread overview]
Message-ID: <a6e2823f-75be-4e1c-990e-a947a5d08d2e@linaro.org> (raw)
In-Reply-To: <20220512170321.mnjpbwlurqkuxkrl@google.com>
On 12/05/2022 14:03, Fangrui Song wrote:
> On 2022-05-12, Adhemerval Zanella wrote:
>> The errlist.c is build with -fno-toplevel-reorder to avoid compiler to
>> reorder the compat assembly directives due a static linker issue [1]
>> (fixed on 2.39).
>
> From https://sourceware.org/pipermail/libc-alpha/2022-May/138657.html
>
> s/build/built
> s/static linker/assembler/
Oops, I though I had these fixed.
>
> Otherwise looks good.
>
> Reviewed-by: Fangrui Song <maskray@google.com>
Thanks.
>
>> This patch removes the compiler flags by split the compat symbol
>> generation in two phases. First the _sys_errlist_internal internal
>> without any compat symbol directive is preprocessed to generate an
>> assembly source code. This generate assembly is then used as input
>> on a platform agnostic errlist-data.S which then creates the compat
>> definitions. This prevents compiler to move any compat directive
>> prior the _sys_errlist_internal definition itself.
>>
>> Checked on a make check run-built-tests=no on all affected ABIs.
>>
>> [1] https://sourceware.org/bugzilla/show_bug.cgi?id=29012
>> ---
>> Makeconfig | 3 +-
>> include/stdio.h | 1 +
>> stdio-common/Makefile | 20 ++++++++++-
>> stdio-common/err_map.h | 24 +++++++++++++
>> stdio-common/errlist-compat-data.h | 1 +
>> stdio-common/errlist-compat.c | 1 -
>> stdio-common/errlist-data-gen.c | 34 +++++++++++++++++++
>> stdio-common/errlist-data.S | 7 ++++
>> stdio-common/errlist.c | 20 +++--------
>> sysdeps/mach/hurd/{errlist.c => err_map.h} | 9 +++--
>> ...errlist-compat.c => errlist-compat-data.h} | 0
>> ...errlist-compat.c => errlist-compat-data.h} | 0
>> sysdeps/unix/sysv/linux/errlist-compat.h | 33 +++++++++++-------
>> ...errlist-compat.c => errlist-compat-data.h} | 0
>> ...errlist-compat.c => errlist-compat-data.h} | 0
>> ...errlist-compat.c => errlist-compat-data.h} | 0
>> 16 files changed, 120 insertions(+), 33 deletions(-)
>> create mode 100644 stdio-common/err_map.h
>> create mode 100644 stdio-common/errlist-compat-data.h
>> delete mode 100644 stdio-common/errlist-compat.c
>> create mode 100644 stdio-common/errlist-data-gen.c
>> create mode 100644 stdio-common/errlist-data.S
>> rename sysdeps/mach/hurd/{errlist.c => err_map.h} (83%)
>> rename sysdeps/unix/sysv/linux/alpha/{errlist-compat.c => errlist-compat-data.h} (100%)
>> rename sysdeps/unix/sysv/linux/{errlist-compat.c => errlist-compat-data.h} (100%)
>> rename sysdeps/unix/sysv/linux/hppa/{errlist-compat.c => errlist-compat-data.h} (100%)
>> rename sysdeps/unix/sysv/linux/mips/{errlist-compat.c => errlist-compat-data.h} (100%)
>> rename sysdeps/unix/sysv/linux/sparc/{errlist-compat.c => errlist-compat-data.h} (100%)
>>
>> diff --git a/Makeconfig b/Makeconfig
>> index 760f14e92f..b5aa07c4f4 100644
>> --- a/Makeconfig
>> +++ b/Makeconfig
>> @@ -1030,7 +1030,8 @@ ifeq (yes,$(build-shared))
>> # Under --enable-shared, we will build a shared library of PIC objects.
>> # The PIC object files are named foo.os.
>> object-suffixes += .os
>> -CPPFLAGS-.os = -DPIC -DSHARED
>> +pic-cppflags = -DPIC -DSHARED
>> +CPPFLAGS-.os = $(pic-cppflags)
>> CFLAGS-.os = $(filter %frame-pointer,$(+cflags)) $(pic-ccflag)
>> libtype.os := lib%_pic.a
>> # This can be changed by a sysdep makefile
>> diff --git a/include/stdio.h b/include/stdio.h
>> index 23b7fd288c..a6f7fd43cb 100644
>> --- a/include/stdio.h
>> +++ b/include/stdio.h
>> @@ -180,6 +180,7 @@ int __vfxprintf (FILE *__fp, const char *__fmt, __gnuc_va_list,
>> attribute_hidden;
>>
>> extern const char *const _sys_errlist_internal[] attribute_hidden;
>> +extern const size_t _sys_errlist_internal_len attribute_hidden;
>> extern const char *__get_errlist (int) attribute_hidden;
>> extern const char *__get_errname (int) attribute_hidden;
>>
>> diff --git a/stdio-common/Makefile b/stdio-common/Makefile
>> index a1603e82fe..08bc998436 100644
>> --- a/stdio-common/Makefile
>> +++ b/stdio-common/Makefile
>> @@ -88,6 +88,7 @@ routines := \
>>
>> aux := \
>> errlist \
>> + errlist-data \
>> errname \
>> fxprintf \
>> printf-parsemb \
>> @@ -211,6 +212,10 @@ tests := \
>> xbug \
>> # tests
>>
>> +generated += \
>> + errlist-data-aux-shared.S \
>> + errlist-data-aux.S \
>> + # generated
>>
>> test-srcs = tst-unbputc tst-printf tst-printfsz-islongdouble
>>
>> @@ -246,6 +251,20 @@ tests-special += $(objpfx)tst-errno-manual.out
>>
>> include ../Rules
>>
>> +# The errlist.c is built in two phases because compiler might reorder the
>> +# compat_symbol directive prior the object itself and on binutils older
>> +# than 2.29 it might generate object sizes different than the expected ones.
>> +$(objpfx)errlist-data-aux-shared.S: errlist-data-gen.c
>> + $(make-target-directory)
>> + $(compile-command.c) $(pic-cppflags) $(pic-ccflag) $(no-stack-protector) -S
>> +
>> +$(objpfx)errlist-data-aux.S: errlist-data-gen.c
>> + $(make-target-directory)
>> + $(compile-command.c) $(pie-default) $(no-stack-protector) -S
>
> Thanks for fixing the extension name (o->S) in v2.
>
>> +$(objpfx)errlist-data.os: $(objpfx)errlist-data-aux-shared.S
>> +$(objpfx)errlist-data.o: $(objpfx)errlist-data-aux.S
>> +
>> ifeq ($(run-built-tests),yes)
>> LOCALES := \
>> de_DE.ISO-8859-1 \
>> @@ -334,7 +353,6 @@ CFLAGS-isoc99_vfscanf.c += -fexceptions
>> CFLAGS-isoc99_vscanf.c += -fexceptions
>> CFLAGS-isoc99_fscanf.c += -fexceptions
>> CFLAGS-isoc99_scanf.c += -fexceptions
>> -CFLAGS-errlist.c += $(fno-unit-at-a-time)
>> CFLAGS-siglist.c += $(fno-unit-at-a-time)
>>
>> # scanf14a.c and scanf16a.c test a deprecated extension which is no
>> diff --git a/stdio-common/err_map.h b/stdio-common/err_map.h
>> new file mode 100644
>> index 0000000000..6cc3aa3375
>> --- /dev/null
>> +++ b/stdio-common/err_map.h
>> @@ -0,0 +1,24 @@
>> +/* Internal errno names mapping definition.
>> + Copyright (C) 2022 Free Software Foundation, Inc.
>> + This file is part of the GNU C Library.
>> +
>> + The GNU C Library is free software; you can redistribute it and/or
>> + modify it under the terms of the GNU Lesser General Public
>> + License as published by the Free Software Foundation; either
>> + version 2.1 of the License, or (at your option) any later version.
>> +
>> + The GNU C Library is distributed in the hope that it will be useful,
>> + but WITHOUT ANY WARRANTY; without even the implied warranty of
>> + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
>> + Lesser General Public License for more details.
>> +
>> + You should have received a copy of the GNU Lesser General Public
>> + License along with the GNU C Library; if not, see
>> + <https://www.gnu.org/licenses/>. */
>> +
>> +#ifndef _ERR_MAP_H
>> +#define _ERR_MAP_H
>> +
>> +#define ERR_MAP(n) (n)
>> +
>> +#endif
>> diff --git a/stdio-common/errlist-compat-data.h b/stdio-common/errlist-compat-data.h
>> new file mode 100644
>> index 0000000000..7c89c9a5a4
>> --- /dev/null
>> +++ b/stdio-common/errlist-compat-data.h
>> @@ -0,0 +1 @@
>> +/* Empty */
>> diff --git a/stdio-common/errlist-compat.c b/stdio-common/errlist-compat.c
>> deleted file mode 100644
>> index 6e25b021ab..0000000000
>> --- a/stdio-common/errlist-compat.c
>> +++ /dev/null
>> @@ -1 +0,0 @@
>> -/* Empty. */
>> diff --git a/stdio-common/errlist-data-gen.c b/stdio-common/errlist-data-gen.c
>> new file mode 100644
>> index 0000000000..db4f50e6db
>> --- /dev/null
>> +++ b/stdio-common/errlist-data-gen.c
>> @@ -0,0 +1,34 @@
>> +/* Internal errno names mapping definition.
>> + Copyright (C) 2022 Free Software Foundation, Inc.
>> + This file is part of the GNU C Library.
>> +
>> + The GNU C Library is free software; you can redistribute it and/or
>> + modify it under the terms of the GNU Lesser General Public
>> + License as published by the Free Software Foundation; either
>> + version 2.1 of the License, or (at your option) any later version.
>> +
>> + The GNU C Library is distributed in the hope that it will be useful,
>> + but WITHOUT ANY WARRANTY; without even the implied warranty of
>> + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
>> + Lesser General Public License for more details.
>> +
>> + You should have received a copy of the GNU Lesser General Public
>> + License along with the GNU C Library; if not, see
>> + <https://www.gnu.org/licenses/>. */
>> +
>> +#include <array_length.h>
>> +#include <err_map.h>
>> +#include <errno.h>
>> +#include <libintl.h>
>> +#include <stdio.h>
>> +
>> +const char *const _sys_errlist_internal[] =
>> + {
>> +#define _S(n, str) [ERR_MAP(n)] = str,
>> +#include <errlist.h>
>> +#undef _S
>> + };
>> +const size_t _sys_errlist_internal_len = array_length (_sys_errlist_internal);
>> +
>> +/* Include to get the definitions for sys_nerr/_sys_nerr. */
>> +#include <errlist-compat-data.h>
>> diff --git a/stdio-common/errlist-data.S b/stdio-common/errlist-data.S
>> new file mode 100644
>> index 0000000000..870b3f40c9
>> --- /dev/null
>> +++ b/stdio-common/errlist-data.S
>> @@ -0,0 +1,7 @@
>> +#ifdef SHARED
>> +# include "errlist-data-aux-shared.S"
>> +#else
>> +# include "errlist-data-aux.S"
>> +#endif
>> +
>> +#include <errlist-compat-data.h>
>> diff --git a/stdio-common/errlist.c b/stdio-common/errlist.c
>> index 1c09a31a7a..4c0a0a218d 100644
>> --- a/stdio-common/errlist.c
>> +++ b/stdio-common/errlist.c
>> @@ -16,29 +16,17 @@
>> License along with the GNU C Library; if not, see
>> <https://www.gnu.org/licenses/>. */
>>
>> -#include <stdio.h>
>> +#include <array_length.h>
>> +#include <err_map.h>
>> #include <errno.h>
>> #include <libintl.h>
>> -#include <array_length.h>
>> -
>> -#ifndef ERR_MAP
>> -# define ERR_MAP(n) n
>> -#endif
>> -
>> -const char *const _sys_errlist_internal[] =
>> - {
>> -#define _S(n, str) [ERR_MAP(n)] = str,
>> -#include <errlist.h>
>> -#undef _S
>> - };
>> +#include <stdio.h>
>>
>> const char *
>> __get_errlist (int errnum)
>> {
>> int mapped = ERR_MAP (errnum);
>> - if (mapped >= 0 && mapped < array_length (_sys_errlist_internal))
>> + if (mapped >= 0 && mapped < _sys_errlist_internal_len)
>> return _sys_errlist_internal[mapped];
>> return NULL;
>> }
>> -
>> -#include <errlist-compat.c>
>> diff --git a/sysdeps/mach/hurd/errlist.c b/sysdeps/mach/hurd/err_map.h
>> similarity index 83%
>> rename from sysdeps/mach/hurd/errlist.c
>> rename to sysdeps/mach/hurd/err_map.h
>> index 2d782ffc67..22d21ca9f1 100644
>> --- a/sysdeps/mach/hurd/errlist.c
>> +++ b/sysdeps/mach/hurd/err_map.h
>> @@ -1,4 +1,5 @@
>> -/* Copyright (C) 1998-2022 Free Software Foundation, Inc.
>> +/* Internal errno names mapping definition. Hurd version.
>> + Copyright (C) 2022 Free Software Foundation, Inc.
>> This file is part of the GNU C Library.
>>
>> The GNU C Library is free software; you can redistribute it and/or
>> @@ -15,7 +16,11 @@
>> License along with the GNU C Library; if not, see
>> <https://www.gnu.org/licenses/>. */
>>
>> +#ifndef _ERR_MAP_H
>> +#define _ERR_MAP_H
>> +
>> #include <mach/error.h>
>>
>> #define ERR_MAP(value) err_get_code (value)
>> -#include <stdio-common/errlist.c>
>> +
>> +#endif
>> diff --git a/sysdeps/unix/sysv/linux/alpha/errlist-compat.c b/sysdeps/unix/sysv/linux/alpha/errlist-compat-data.h
>> similarity index 100%
>> rename from sysdeps/unix/sysv/linux/alpha/errlist-compat.c
>> rename to sysdeps/unix/sysv/linux/alpha/errlist-compat-data.h
>> diff --git a/sysdeps/unix/sysv/linux/errlist-compat.c b/sysdeps/unix/sysv/linux/errlist-compat-data.h
>> similarity index 100%
>> rename from sysdeps/unix/sysv/linux/errlist-compat.c
>> rename to sysdeps/unix/sysv/linux/errlist-compat-data.h
>> diff --git a/sysdeps/unix/sysv/linux/errlist-compat.h b/sysdeps/unix/sysv/linux/errlist-compat.h
>> index a09b38f243..33008863f8 100644
>> --- a/sysdeps/unix/sysv/linux/errlist-compat.h
>> +++ b/sysdeps/unix/sysv/linux/errlist-compat.h
>> @@ -20,6 +20,7 @@
>> #define _ERRLIST_COMPAT_H
>>
>> #include <shlib-compat.h>
>> +#include <limits.h>
>>
>> /* Define new compat symbols for symbols _sys_errlist, sys_errlist,
>> _sys_nerr, and sys_nerr for version VERSION with NUMBERERR times number of
>> @@ -27,17 +28,25 @@
>> Both _sys_errlist and sys_errlist alias to _sys_errlist_internal symbol
>> (defined on errlist.c) while _sys_nerr and sys_nerr created new variable
>> with the expected size. */
>> -#define DEFINE_COMPAT_ERRLIST(NUMBERERR, VERSION) \
>> - const int __##VERSION##_sys_nerr = NUMBERERR; \
>> - strong_alias (__##VERSION##_sys_nerr, __##VERSION##__sys_nerr); \
>> - declare_symbol_alias (__ ## VERSION ## _sys_errlist, _sys_errlist_internal,\
>> - object, NUMBERERR * (ULONG_WIDTH / UCHAR_WIDTH)); \
>> - declare_symbol_alias (__ ## VERSION ## __sys_errlist, \
>> - _sys_errlist_internal, object, \
>> - NUMBERERR * (ULONG_WIDTH / UCHAR_WIDTH)); \
>> - compat_symbol (libc, __## VERSION ## _sys_nerr, sys_nerr, VERSION); \
>> - compat_symbol (libc, __## VERSION ## __sys_nerr, _sys_nerr, VERSION); \
>> - compat_symbol (libc, __## VERSION ## _sys_errlist, sys_errlist, VERSION); \
>> - compat_symbol (libc, __## VERSION ## __sys_errlist, _sys_errlist, VERSION);\
>> +#ifdef __ASSEMBLER__
>> +# define DEFINE_COMPAT_ERRLIST(NUMBERERR, VERSION) \
>> + declare_object_symbol_alias (__ ## VERSION ## _sys_errlist, \
>> + _sys_errlist_internal, \
>> + NUMBERERR * (ULONG_WIDTH / UCHAR_WIDTH)) \
>> + ASM_LINE_SEP \
>> + declare_object_symbol_alias (__ ## VERSION ## __sys_errlist, \
>> + _sys_errlist_internal, \
>> + NUMBERERR * (ULONG_WIDTH / UCHAR_WIDTH)) \
>> + ASM_LINE_SEP \
>> + compat_symbol (libc, __## VERSION ## _sys_errlist, sys_errlist, VERSION) \
>> + ASM_LINE_SEP \
>> + compat_symbol (libc, __## VERSION ## __sys_errlist, _sys_errlist, VERSION)
>> +#else
>> +# define DEFINE_COMPAT_ERRLIST(NUMBERERR, VERSION) \
>> + const int __##VERSION##_sys_nerr = NUMBERERR; \
>> + strong_alias (__##VERSION##_sys_nerr, __##VERSION##__sys_nerr); \
>> + compat_symbol (libc, __## VERSION ## _sys_nerr, sys_nerr, VERSION); \
>> + compat_symbol (libc, __## VERSION ## __sys_nerr, _sys_nerr, VERSION);
>> +#endif
>>
>> #endif
>> diff --git a/sysdeps/unix/sysv/linux/hppa/errlist-compat.c b/sysdeps/unix/sysv/linux/hppa/errlist-compat-data.h
>> similarity index 100%
>> rename from sysdeps/unix/sysv/linux/hppa/errlist-compat.c
>> rename to sysdeps/unix/sysv/linux/hppa/errlist-compat-data.h
>> diff --git a/sysdeps/unix/sysv/linux/mips/errlist-compat.c b/sysdeps/unix/sysv/linux/mips/errlist-compat-data.h
>> similarity index 100%
>> rename from sysdeps/unix/sysv/linux/mips/errlist-compat.c
>> rename to sysdeps/unix/sysv/linux/mips/errlist-compat-data.h
>> diff --git a/sysdeps/unix/sysv/linux/sparc/errlist-compat.c b/sysdeps/unix/sysv/linux/sparc/errlist-compat-data.h
>> similarity index 100%
>> rename from sysdeps/unix/sysv/linux/sparc/errlist-compat.c
>> rename to sysdeps/unix/sysv/linux/sparc/errlist-compat-data.h
>> --
>> 2.34.1
>>
next prev parent reply other threads:[~2022-05-12 20:03 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-05-12 12:59 [PATCH v2 0/4] Remove fno_unit_at_a_time configure check Adhemerval Zanella
2022-05-12 12:59 ` [PATCH v2 1/4] Add declare_object_symbol_alias for assembly codes (BZ #28128) Adhemerval Zanella
2022-05-12 16:52 ` Fangrui Song
2022-05-12 12:59 ` [PATCH v2 2/4] stdio: Remove the usage of $(fno-unit-at-a-time) for errlist.c Adhemerval Zanella
2022-05-12 17:03 ` Fangrui Song
2022-05-12 20:03 ` Adhemerval Zanella [this message]
2022-05-12 12:59 ` [PATCH v2 3/4] stdio: Remove the usage of $(fno-unit-at-a-time) for siglist.c Adhemerval Zanella
2022-05-12 17:06 ` Fangrui Song
2022-05-12 20:04 ` Adhemerval Zanella
2022-05-12 12:59 ` [PATCH v2 4/4] Remove configure fno_unit_at_a_time Adhemerval Zanella
2022-05-12 17:07 ` Fangrui Song
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