From 7a45d4d688d4966664ca94619b2ad0fc8d333d77 Mon Sep 17 00:00:00 2001
From: Zdenek Kabelac <zkabelac@redhat.com>
Date: Mon, 29 Mar 2021 21:46:12 +0200
Subject: [PATCH] configure: support builds without versioning
Not all libc (like musl, uclibc dietlibc) libraries support full symbol
version resolution in runtime like glibc.
Add support to not generate symbol versions when compiling against them.
Additionally libdevmapper.so was broken when compiled against
uclibc. Runtime linker loader caused calling dm_task_get_info_base()
function recursively, leading to segmentation fault.
Introduce --with-symvers=STYLE option, which allows to choose
between gnu and disabled symbol versioning. By default gnu symbol
versioning is used.
__GNUC__ check is replaced now with GNU_SYMVER.
Additionally ld version script is included only in
case of gnu option, which slightly reduces output size.
Providing --without-symvers to configure script when building against
uclibc library fixes segmentation fault error described above, due to
lack of several versions of the same symbol in libdevmapper.so
library.
Based on:
https://patchwork.kernel.org/project/dm-devel/patch/20180831144817.31207-1-m.niestroj@grinn-global.com/
Suggested-by: Marcin Niestroj <m.niestroj@grinn-global.com>
---
configure | 35 ++++++++++++++++++++++++++++++++---
configure.ac | 26 +++++++++++++++++++++++---
include/configure.h.in | 3 +++
lib/misc/lib.h | 4 ++--
libdm/datastruct/bitset.c | 4 +---
libdm/ioctl/libdm-iface.c | 2 +-
libdm/libdm-deptree.c | 2 +-
libdm/libdm-stats.c | 2 +-
8 files changed, 64 insertions(+), 14 deletions(-)
diff --git a/configure b/configure
index bb8d502209d60..eeb8397a27d0b 100755
--- a/configure
+++ b/configure
@@ -942,6 +942,7 @@ enable_cmirrord
with_cmirrord_pidfile
enable_debug
with_optimisation
+with_symvers
enable_profiling
enable_valgrind_pool
enable_devmapper
@@ -1792,6 +1793,8 @@ Optional Packages:
--with-cmirrord-pidfile=PATH
cmirrord pidfile [PID_DIR/cmirrord.pid]
--with-optimisation=OPT C optimisation flag [OPT=-O2]
+ --with-symvers=STYLE use symbol versioning of the shared library
+ [default=gnu]
--with-lvmlockd-pidfile=PATH
lvmlockd pidfile [PID_DIR/lvmlockd.pid]
--with-lvmetad-pidfile=PATH
@@ -3168,13 +3171,11 @@ if test -z "$CFLAGS"; then :
fi
case "$host_os" in
linux*)
- CLDFLAGS="$CLDFLAGS -Wl,--version-script,.export.sym"
# equivalent to -rdynamic
ELDFLAGS="-Wl,--export-dynamic"
# FIXME Generate list and use --dynamic-list=.dlopen.sym
CLDWHOLEARCHIVE="-Wl,-whole-archive"
CLDNOWHOLEARCHIVE="-Wl,-no-whole-archive"
- LDDEPS="$LDDEPS .export.sym"
LIB_SUFFIX=so
DEVMAPPER=yes
BUILD_LVMETAD=no
@@ -3190,7 +3191,6 @@ case "$host_os" in
;;
darwin*)
CFLAGS="$CFLAGS -no-cpp-precomp -fno-common"
- CLDFLAGS="$CLDFLAGS"
ELDFLAGS=
CLDWHOLEARCHIVE="-all_load"
CLDNOWHOLEARCHIVE=
@@ -11182,6 +11182,35 @@ fi
{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $COPTIMISE_FLAG" >&5
$as_echo "$COPTIMISE_FLAG" >&6; }
+################################################################################
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking whether to use symbol versioning" >&5
+$as_echo_n "checking whether to use symbol versioning... " >&6; }
+
+# Check whether --with-symvers was given.
+if test "${with_symvers+set}" = set; then :
+ withval=$with_symvers; case "$withval" in
+ gnu|no) symvers=$withval ;;
+ *) as_fn_error $? "Unknown argument to with-symvers" "$LINENO" 5 ;;
+ esac
+else
+ symvers=gnu
+fi
+
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $symvers" >&5
+$as_echo "$symvers" >&6; }
+
+if test "$GCC" = "yes" && test "$symvers" = "gnu" ; then
+
+$as_echo "#define GNU_SYMVER 1" >>confdefs.h
+
+ case "$host_os" in
+ linux*)
+ CLDFLAGS="${CLDFLAGS-"$LDFLAGS"} -Wl,--version-script,.export.sym"
+ LDDEPS="$LDDEPS .export.sym"
+ ;;
+ esac
+fi
+
################################################################################
{ $as_echo "$as_me:${as_lineno-$LINENO}: checking whether to gather gcov profiling data" >&5
$as_echo_n "checking whether to gather gcov profiling data... " >&6; }
diff --git a/configure.ac b/configure.ac
index f040a5a713d7f..a2697d15c9150 100644
--- a/configure.ac
+++ b/configure.ac
@@ -30,13 +30,11 @@ AC_CANONICAL_TARGET([])
AS_IF([test -z "$CFLAGS"], [COPTIMISE_FLAG="-O2"])
case "$host_os" in
linux*)
- CLDFLAGS="$CLDFLAGS -Wl,--version-script,.export.sym"
# equivalent to -rdynamic
ELDFLAGS="-Wl,--export-dynamic"
# FIXME Generate list and use --dynamic-list=.dlopen.sym
CLDWHOLEARCHIVE="-Wl,-whole-archive"
CLDNOWHOLEARCHIVE="-Wl,-no-whole-archive"
- LDDEPS="$LDDEPS .export.sym"
LIB_SUFFIX=so
DEVMAPPER=yes
BUILD_LVMETAD=no
@@ -52,7 +50,6 @@ case "$host_os" in
;;
darwin*)
CFLAGS="$CFLAGS -no-cpp-precomp -fno-common"
- CLDFLAGS="$CLDFLAGS"
ELDFLAGS=
CLDWHOLEARCHIVE="-all_load"
CLDNOWHOLEARCHIVE=
@@ -981,6 +978,29 @@ AC_ARG_WITH(optimisation,
COPTIMISE_FLAG=$withval)
AC_MSG_RESULT($COPTIMISE_FLAG)
+################################################################################
+dnl -- Symbol versioning
+AC_MSG_CHECKING(whether to use symbol versioning)
+AC_ARG_WITH(symvers,
+ AC_HELP_STRING([--with-symvers=STYLE],
+ [use symbol versioning of the shared library [default=gnu]]),
+ [ case "$withval" in
+ gnu|no) symvers=$withval ;;
+ *) AC_MSG_ERROR(Unknown argument to with-symvers) ;;
+ esac], symvers=gnu)
+AC_MSG_RESULT($symvers)
+
+if test "$GCC" = "yes" && test "$symvers" = "gnu" ; then
+ AC_DEFINE(GNU_SYMVER, 1,
+ [Define to use GNU versioning in the shared library.])
+ case "$host_os" in
+ linux*)
+ CLDFLAGS="${CLDFLAGS-"$LDFLAGS"} -Wl,--version-script,.export.sym"
+ LDDEPS="$LDDEPS .export.sym"
+ ;;
+ esac
+fi
+
################################################################################
dnl -- Enable profiling
AC_MSG_CHECKING(whether to gather gcov profiling data)
diff --git a/include/configure.h.in b/include/configure.h.in
index 49663e484e0b2..af0fa31e063a3 100644
--- a/include/configure.h.in
+++ b/include/configure.h.in
@@ -150,6 +150,9 @@
/* Path to fsadm binary. */
#undef FSADM_PATH
+/* Define to use GNU versioning in the shared library. */
+#undef GNU_SYMVER
+
/* Define to 1 if you have the `alarm' function. */
#undef HAVE_ALARM
diff --git a/lib/misc/lib.h b/lib/misc/lib.h
index d7fa5c721c118..3cd7a76ae3486 100644
--- a/lib/misc/lib.h
+++ b/lib/misc/lib.h
@@ -42,7 +42,7 @@
* specified version string.
*
* Since versioning is only available when compiling with GCC the entire
- * compatibility version should be enclosed in '#if defined(__GNUC__)',
+ * compatibility version should be enclosed in '#if defined(GNU_SYMVER)',
* for example:
*
* int dm_foo(int bar)
@@ -67,7 +67,7 @@
* versions of library symbols prior to the introduction of symbol
* versioning: it must never be used for new symbols.
*/
-#if defined(__GNUC__)
+#if defined(GNU_SYMVER)
#define DM_EXPORT_SYMBOL(func, ver) \
__asm__(".symver " #func "_v" #ver ", " #func "@DM_" #ver )
#define DM_EXPORT_SYMBOL_BASE(func) \
diff --git a/libdm/datastruct/bitset.c b/libdm/datastruct/bitset.c
index b0826e1eb54ec..642587e5472b1 100644
--- a/libdm/datastruct/bitset.c
+++ b/libdm/datastruct/bitset.c
@@ -242,7 +242,7 @@ bad:
return NULL;
}
-#if defined(__GNUC__)
+#if defined(GNU_SYMVER)
/*
* Maintain backward compatibility with older versions that did not
* accept a 'min_num_bits' argument to dm_bitset_parse_list().
@@ -254,6 +254,4 @@ dm_bitset_t dm_bitset_parse_list_v1_02_129(const char *str, struct dm_pool *mem)
}
DM_EXPORT_SYMBOL(dm_bitset_parse_list, 1_02_129);
-#else /* if defined(__GNUC__) */
-
#endif
diff --git a/libdm/ioctl/libdm-iface.c b/libdm/ioctl/libdm-iface.c
index 14186e680d97d..4be7ab34a704f 100644
--- a/libdm/ioctl/libdm-iface.c
+++ b/libdm/ioctl/libdm-iface.c
@@ -2176,7 +2176,7 @@ void dm_lib_exit(void)
_version_checked = 0;
}
-#if defined(__GNUC__)
+#if defined(GNU_SYMVER)
/*
* Maintain binary backward compatibility.
* Version script mechanism works with 'gcc' compatible compilers only.
diff --git a/libdm/libdm-deptree.c b/libdm/libdm-deptree.c
index ba1ed1991a0cf..802db076e27f1 100644
--- a/libdm/libdm-deptree.c
+++ b/libdm/libdm-deptree.c
@@ -3849,7 +3849,7 @@ void dm_tree_node_set_callback(struct dm_tree_node *dnode,
dnode->callback_data = data;
}
-#if defined(__GNUC__)
+#if defined(GNU_SYMVER)
/*
* Backward compatible implementations.
*
diff --git a/libdm/libdm-stats.c b/libdm/libdm-stats.c
index a3697c74dfde8..9f09f1c2f082e 100644
--- a/libdm/libdm-stats.c
+++ b/libdm/libdm-stats.c
@@ -5069,7 +5069,7 @@ int dm_stats_start_filemapd(int fd, uint64_t group_id, const char *path,
* current dm_stats_create_region() version.
*/
-#if defined(__GNUC__)
+#if defined(GNU_SYMVER)
int dm_stats_create_region_v1_02_106(struct dm_stats *dms, uint64_t *region_id,
uint64_t start, uint64_t len, int64_t step,
int precise, const char *program_id,
--
2.33.1