From: Fangrui Song <maskray@google.com>
To: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Cc: libc-alpha@sourceware.org
Subject: Re: [PATCH 2/4] stdio: Remove the usage of $(fno-unit-at-a-time) for errlist.c
Date: Wed, 11 May 2022 23:27:25 -0700 [thread overview]
Message-ID: <20220512062725.cvlxegifjrpsei6d@google.com> (raw)
In-Reply-To: <20220511195457.410681-3-adhemerval.zanella@linaro.org>
On 2022-05-11, 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).
s/build/built
s/static linker/assembler/
>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
>---
> include/stdio.h | 1 +
> stdio-common/Makefile | 17 +++++++++-
> 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
> 15 files changed, 115 insertions(+), 32 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/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..087acb82b6 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.os \
>+ errlist-data-aux.o \
>+ # generated
>
> test-srcs = tst-unbputc tst-printf tst-printfsz-islongdouble
>
>@@ -246,6 +251,17 @@ tests-special += $(objpfx)tst-errno-manual.out
>
> include ../Rules
>
>+$(objpfx)errlist-data-aux.os: errlist-data-gen.c
>+ $(make-target-directory)
>+ $(compile-command.c) $(no-stack-protector) -S
>+
>+$(objpfx)errlist-data-aux.o: errlist-data-gen.c
>+ $(make-target-directory)
>+ $(compile-command.c) $(no-stack-protector) -S
The -S usage is clever:)
The two-stage approach may need a comment in Makefile, so that this can
be cleaned up when glibc requires 2.39... (in 203x? :) )
>+$(objpfx)errlist-data.os: $(objpfx)errlist-data-aux.os
>+$(objpfx)errlist-data.o: $(objpfx)errlist-data-aux.o
>+
> ifeq ($(run-built-tests),yes)
> LOCALES := \
> de_DE.ISO-8859-1 \
>@@ -334,7 +350,6 @@ 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..a9856c5080
>--- /dev/null
>+++ b/stdio-common/errlist-data.S
>@@ -0,0 +1,7 @@
>+#ifdef SHARED
>+# include "errlist-data-aux.os"
>+#else
>+# include "errlist-data-aux.o"
>+#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 6:27 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-05-11 19:54 [PATCH 0/4] Remove fno_unit_at_a_time configure check Adhemerval Zanella
2022-05-11 19:54 ` [PATCH 1/4] Add declare_object_symbol_alias for assembly codes (BZ #28128) Adhemerval Zanella
2022-05-11 19:54 ` [PATCH 2/4] stdio: Remove the usage of $(fno-unit-at-a-time) for errlist.c Adhemerval Zanella
2022-05-12 6:27 ` Fangrui Song [this message]
2022-05-12 7:44 ` Andreas Schwab
2022-05-11 19:54 ` [PATCH 3/4] stdio: Remove the usage of $(fno-unit-at-a-time) for siglist.c Adhemerval Zanella
2022-05-11 19:54 ` [PATCH 4/4] Remove configure fno_unit_at_a_time Adhemerval Zanella
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