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Ping[3]: [PATCH v4] Destructor support for C++11 thread_localvariables
- From: Siddhesh Poyarekar <siddhesh at redhat dot com>
- To: libc-alpha at sourceware dot org
- Cc: Jakub Jelinek <jakub at redhat dot com>, Jason Merrill <jason at redhat dot com>, Roland McGrath <roland at hack dot frob dot com>
- Date: Fri, 14 Dec 2012 15:31:21 +0530
- Subject: Ping[3]: [PATCH v4] Destructor support for C++11 thread_localvariables
- References: <20121017184033.109bcd89@spoyarek><20121029085207.21957cd2@spoyarek><20121029063837.GH1752@tucnak.redhat.com><20121030193603.3993aa3c@spoyarek><20121030200754.3680c8ba@spoyarek><20121105163606.0b126f51@spoyarek><20121115140548.31c9aa9a@spoyarek>
On Thu, Nov 15, 2012 at 02:05:48PM +0530, Siddhesh Poyarekar wrote:
> > http://sourceware.org/ml/libc-alpha/2012-10/msg00858.html
> >
Hi,
I've updated this patch for 2.18 along with fixes for a few problems I
saw now. I noticed that this requirement has been added to the
projects list on the wiki as well:
http://sourceware.org/glibc/wiki/Development_Todo/Generic
To summarize, this patch adds destructor support for the C++11
variables of the thread_local scope. it adds a new function
__cxa_thread_atexit_impl, that libstdc++ calls to register destructors
for the thread_local objects it constructs. The destructors will then
be called at either thread exit or program exit. This patch also
ensures that DSOs defining thread_local objects are not unloaded till
destructors of all those objects are called. The previous thread is
here:
http://sourceware.org/ml/libc-alpha/2012-10/msg00289.html
Siddhesh
ChangeLog:
2012-12-14 Siddhesh Poyarekar <siddhesh@redhat.com>
* Versions.def: Add GLIBC_2.18.
* include/link.h (struct link_map): New member l_tls_dtor_count.
* include/stdlib.h (__cxa_thread_atexit_impl): Declare.
(__call_tls_dtors): Likewise.
* sysdeps/unix/sysv/linux/i386/nptl/libc.abilist: Add
__cxa_thread_atexit_impl.
* sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/nptl/libc.abilist:
Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/nptl/libc.abilist:
Likewise.
* sysdeps/unix/sysv/linux/s390/s390-32/nptl/libc.abilist:
Likewise.
* sysdeps/unix/sysv/linux/s390/s390-64/nptl/libc.abilist:
Likewise.
* sysdeps/unix/sysv/linux/sh/nptl/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc32/nptl/libc.abilist:
Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc64/nptl/libc.abilist:
Likewise.
* sysdeps/unix/sysv/linux/x86_64/64/nptl/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/x86_64/x32/nptl/libc.abilist:
Likewise.
* stdlib/Makefile (routines): Add __cxa_thread_atexit_impl.
(tests): Add test case tst-tls-atexit.
(modules-names): Add shared library for tst-tls-atexit.
* stdlib/Versions (GLIBC_2.17): Add __cxa_thread_atexit_impl.
(GLIBC_PRIVATE): Add __call_tls_dtors.
* stdlib/cxa_thread_atexit_impl.c: New file with helper function
for libstdc++.
* stdlib/exit.c (__run_exit_handlers): Call __call_tls_dtors.
* stdlib/tst-tls-atexit.c: New test case.
* stdlib/tst-tls-atexit-lib.c: New test case.
ports/ChangeLog.alpha:
2012-12-14 Siddhesh Poyarekar <siddhesh@redhat.com>
* sysdeps/unix/sysv/linux/alpha/nptl/libc.abilist: Add
__cxa_thread_atexit_impl.
ports/ChangeLog.arm:
2012-12-14 Siddhesh Poyarekar <siddhesh@redhat.com>
* sysdeps/unix/sysv/linux/arm/nptl/libc.abilist: Add
__cxa_thread_atexit_impl.
ports/ChangeLog.ia64:
2012-12-14 Siddhesh Poyarekar <siddhesh@redhat.com>
* sysdeps/unix/sysv/linux/ia64/nptl/libc.abilist: Add
__cxa_thread_atexit_impl.
ports/ChangeLog.m68k:
2012-12-14 Siddhesh Poyarekar <siddhesh@redhat.com>
* sysdeps/unix/sysv/linux/m68k/coldfire/nptl/libc.abilist: Add
__cxa_thread_atexit_impl.
* sysdeps/unix/sysv/linux/m68k/m680x0/nptl/libc.abilist:
Likewise.
ports/ChangeLog.mips:
2012-12-14 Siddhesh Poyarekar <siddhesh@redhat.com>
* sysdeps/unix/sysv/linux/mips/mips32/nptl/libc.abilist: Add
__cxa_thread_atexit_impl.
* sysdeps/unix/sysv/linux/mips/mips64/n32/nptl/libc.abilist:
Likewise.
* sysdeps/unix/sysv/linux/mips/mips64/n64/nptl/libc.abilist:
Likewise.
ports/ChangeLog.powerpc:
2012-12-14 Siddhesh Poyarekar <siddhesh@redhat.com>
* sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/nptl/libc.abilist:
Add __cxa_thread_atexit_impl.
* sysdeps/unix/sysv/linux/tile/tilegx/tilegx32/nptl/libc.abilist:
Likewise.
ports/ChangeLog.tile:
2012-12-14 Siddhesh Poyarekar <siddhesh@redhat.com>
* sysdeps/unix/sysv/linux/tile/tilegx/tilegx64/nptl/libc.abilist:
Add __cxa_thread_atexit_impl.
* sysdeps/unix/sysv/linux/tile/tilepro/nptl/libc.abilist:
Likewise.
diff --git a/Versions.def b/Versions.def
index 3c9e0ae..8651992 100644
--- a/Versions.def
+++ b/Versions.def
@@ -34,6 +34,7 @@ libc {
GLIBC_2.15
GLIBC_2.16
GLIBC_2.17
+ GLIBC_2.18
HURD_CTHREADS_0.3
%ifdef EXPORT_UNWIND_FIND_FDE
GCC_3.0
diff --git a/include/link.h b/include/link.h
index d759064..69a3465 100644
--- a/include/link.h
+++ b/include/link.h
@@ -301,6 +301,9 @@ struct link_map
/* Index of the module in the dtv array. */
size_t l_tls_modid;
+ /* Number of thread_local objects constructed by this DSO. */
+ size_t l_tls_dtor_count;
+
/* Information used to change permission after the relocations are
done. */
ElfW(Addr) l_relro_addr;
diff --git a/include/stdlib.h b/include/stdlib.h
index d45b2f0..4387394 100644
--- a/include/stdlib.h
+++ b/include/stdlib.h
@@ -99,6 +99,10 @@ extern int __cxa_atexit (void (*func) (void *), void *arg, void *d);
extern int __cxa_atexit_internal (void (*func) (void *), void *arg, void *d)
attribute_hidden;
+extern int __cxa_thread_atexit_impl (void (*func) (void *), void *arg,
+ void *d);
+extern void __call_tls_dtors (void);
+
extern void __cxa_finalize (void *d);
extern int __posix_memalign (void **memptr, size_t alignment, size_t size);
diff --git a/nptl/pthread_create.c b/nptl/pthread_create.c
index 197dfa7..34c0d30 100644
--- a/nptl/pthread_create.c
+++ b/nptl/pthread_create.c
@@ -311,6 +311,9 @@ start_thread (void *arg)
#endif
}
+ /* Call destructors for the thread_local TLS variables. */
+ __call_tls_dtors ();
+
/* Run the destructor for the thread-local data. */
__nptl_deallocate_tsd ();
diff --git a/ports/sysdeps/unix/sysv/linux/alpha/nptl/libc.abilist b/ports/sysdeps/unix/sysv/linux/alpha/nptl/libc.abilist
index 1d0cc7e..980e088 100644
--- a/ports/sysdeps/unix/sysv/linux/alpha/nptl/libc.abilist
+++ b/ports/sysdeps/unix/sysv/linux/alpha/nptl/libc.abilist
@@ -1819,6 +1819,9 @@ GLIBC_2.17
clock_nanosleep F
clock_settime F
secure_getenv F
+GLIBC_2.18
+ GLIBC_2.18 A
+ __cxa_thread_atexit_impl F
GLIBC_2.2
GLIBC_2.2 A
_IO_adjust_wcolumn F
diff --git a/ports/sysdeps/unix/sysv/linux/arm/nptl/libc.abilist b/ports/sysdeps/unix/sysv/linux/arm/nptl/libc.abilist
index ceab6b2..ce45208 100644
--- a/ports/sysdeps/unix/sysv/linux/arm/nptl/libc.abilist
+++ b/ports/sysdeps/unix/sysv/linux/arm/nptl/libc.abilist
@@ -86,6 +86,9 @@ GLIBC_2.17
clock_nanosleep F
clock_settime F
secure_getenv F
+GLIBC_2.18
+ GLIBC_2.18 A
+ __cxa_thread_atexit_impl F
GLIBC_2.4
GLIBC_2.4 A
_Exit F
diff --git a/ports/sysdeps/unix/sysv/linux/ia64/nptl/libc.abilist b/ports/sysdeps/unix/sysv/linux/ia64/nptl/libc.abilist
index b3510fe..067552d 100644
--- a/ports/sysdeps/unix/sysv/linux/ia64/nptl/libc.abilist
+++ b/ports/sysdeps/unix/sysv/linux/ia64/nptl/libc.abilist
@@ -86,6 +86,9 @@ GLIBC_2.17
clock_nanosleep F
clock_settime F
secure_getenv F
+GLIBC_2.18
+ GLIBC_2.18 A
+ __cxa_thread_atexit_impl F
GLIBC_2.2
GLIBC_2.2 A
_Exit F
diff --git a/ports/sysdeps/unix/sysv/linux/m68k/coldfire/nptl/libc.abilist b/ports/sysdeps/unix/sysv/linux/m68k/coldfire/nptl/libc.abilist
index 3c40379..f06cc8e 100644
--- a/ports/sysdeps/unix/sysv/linux/m68k/coldfire/nptl/libc.abilist
+++ b/ports/sysdeps/unix/sysv/linux/m68k/coldfire/nptl/libc.abilist
@@ -87,6 +87,9 @@ GLIBC_2.17
clock_nanosleep F
clock_settime F
secure_getenv F
+GLIBC_2.18
+ GLIBC_2.18 A
+ __cxa_thread_atexit_impl F
GLIBC_2.4
GLIBC_2.4 A
_Exit F
diff --git a/ports/sysdeps/unix/sysv/linux/m68k/m680x0/nptl/libc.abilist b/ports/sysdeps/unix/sysv/linux/m68k/m680x0/nptl/libc.abilist
index f998b1b..9010ea7 100644
--- a/ports/sysdeps/unix/sysv/linux/m68k/m680x0/nptl/libc.abilist
+++ b/ports/sysdeps/unix/sysv/linux/m68k/m680x0/nptl/libc.abilist
@@ -1775,6 +1775,9 @@ GLIBC_2.17
clock_nanosleep F
clock_settime F
secure_getenv F
+GLIBC_2.18
+ GLIBC_2.18 A
+ __cxa_thread_atexit_impl F
GLIBC_2.2
GLIBC_2.2 A
_IO_adjust_wcolumn F
diff --git a/ports/sysdeps/unix/sysv/linux/mips/mips32/nptl/libc.abilist b/ports/sysdeps/unix/sysv/linux/mips/mips32/nptl/libc.abilist
index 7378869..f8cefd1 100644
--- a/ports/sysdeps/unix/sysv/linux/mips/mips32/nptl/libc.abilist
+++ b/ports/sysdeps/unix/sysv/linux/mips/mips32/nptl/libc.abilist
@@ -2250,3 +2250,6 @@ GLIBC_2.17
clock_nanosleep F
clock_settime F
secure_getenv F
+GLIBC_2.18
+ GLIBC_2.18 A
+ __cxa_thread_atexit_impl F
diff --git a/ports/sysdeps/unix/sysv/linux/mips/mips64/n32/nptl/libc.abilist b/ports/sysdeps/unix/sysv/linux/mips/mips64/n32/nptl/libc.abilist
index df2e637..9dbbd97 100644
--- a/ports/sysdeps/unix/sysv/linux/mips/mips64/n32/nptl/libc.abilist
+++ b/ports/sysdeps/unix/sysv/linux/mips/mips64/n32/nptl/libc.abilist
@@ -1398,6 +1398,9 @@ GLIBC_2.17
clock_nanosleep F
clock_settime F
secure_getenv F
+GLIBC_2.18
+ GLIBC_2.18 A
+ __cxa_thread_atexit_impl F
GLIBC_2.2
GLIBC_2.2 A
_Exit F
diff --git a/ports/sysdeps/unix/sysv/linux/mips/mips64/n64/nptl/libc.abilist b/ports/sysdeps/unix/sysv/linux/mips/mips64/n64/nptl/libc.abilist
index 22b3068..c7e46aa 100644
--- a/ports/sysdeps/unix/sysv/linux/mips/mips64/n64/nptl/libc.abilist
+++ b/ports/sysdeps/unix/sysv/linux/mips/mips64/n64/nptl/libc.abilist
@@ -1396,6 +1396,9 @@ GLIBC_2.17
clock_nanosleep F
clock_settime F
secure_getenv F
+GLIBC_2.18
+ GLIBC_2.18 A
+ __cxa_thread_atexit_impl F
GLIBC_2.2
GLIBC_2.2 A
_Exit F
diff --git a/ports/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/nptl/libc.abilist b/ports/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/nptl/libc.abilist
index 0efc6b5..9b6d663 100644
--- a/ports/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/nptl/libc.abilist
+++ b/ports/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/nptl/libc.abilist
@@ -1781,6 +1781,9 @@ GLIBC_2.17
clock_nanosleep F
clock_settime F
secure_getenv F
+GLIBC_2.18
+ GLIBC_2.18 A
+ __cxa_thread_atexit_impl F
GLIBC_2.2
GLIBC_2.2 A
_IO_adjust_wcolumn F
diff --git a/ports/sysdeps/unix/sysv/linux/tile/tilegx/tilegx32/nptl/libc.abilist b/ports/sysdeps/unix/sysv/linux/tile/tilegx/tilegx32/nptl/libc.abilist
index d79b2df..caf74b8 100644
--- a/ports/sysdeps/unix/sysv/linux/tile/tilegx/tilegx32/nptl/libc.abilist
+++ b/ports/sysdeps/unix/sysv/linux/tile/tilegx/tilegx32/nptl/libc.abilist
@@ -2088,3 +2088,6 @@ GLIBC_2.17
clock_nanosleep F
clock_settime F
secure_getenv F
+GLIBC_2.18
+ GLIBC_2.18 A
+ __cxa_thread_atexit_impl F
diff --git a/ports/sysdeps/unix/sysv/linux/tile/tilegx/tilegx64/nptl/libc.abilist b/ports/sysdeps/unix/sysv/linux/tile/tilegx/tilegx64/nptl/libc.abilist
index f617405..68d975b 100644
--- a/ports/sysdeps/unix/sysv/linux/tile/tilegx/tilegx64/nptl/libc.abilist
+++ b/ports/sysdeps/unix/sysv/linux/tile/tilegx/tilegx64/nptl/libc.abilist
@@ -2088,3 +2088,6 @@ GLIBC_2.17
clock_nanosleep F
clock_settime F
secure_getenv F
+GLIBC_2.18
+ GLIBC_2.18 A
+ __cxa_thread_atexit_impl F
diff --git a/ports/sysdeps/unix/sysv/linux/tile/tilepro/nptl/libc.abilist b/ports/sysdeps/unix/sysv/linux/tile/tilepro/nptl/libc.abilist
index d79b2df..caf74b8 100644
--- a/ports/sysdeps/unix/sysv/linux/tile/tilepro/nptl/libc.abilist
+++ b/ports/sysdeps/unix/sysv/linux/tile/tilepro/nptl/libc.abilist
@@ -2088,3 +2088,6 @@ GLIBC_2.17
clock_nanosleep F
clock_settime F
secure_getenv F
+GLIBC_2.18
+ GLIBC_2.18 A
+ __cxa_thread_atexit_impl F
diff --git a/stdlib/Makefile b/stdlib/Makefile
index 5e99d7f..20287da 100644
--- a/stdlib/Makefile
+++ b/stdlib/Makefile
@@ -33,7 +33,7 @@ routines := \
bsearch qsort msort \
getenv putenv setenv secure-getenv \
exit on_exit atexit cxa_atexit cxa_finalize old_atexit \
- quick_exit at_quick_exit cxa_at_quick_exit \
+ quick_exit at_quick_exit cxa_at_quick_exit cxa_thread_atexit_impl \
abs labs llabs \
div ldiv lldiv \
mblen mbstowcs mbtowc wcstombs wctomb \
@@ -70,9 +70,11 @@ tests := tst-strtol tst-strtod testmb testrand testsort testdiv \
tst-makecontext2 tst-strtod6 tst-unsetenv1 \
tst-makecontext3 bug-getcontext bug-fmtmsg1 \
tst-secure-getenv tst-strtod-overflow tst-strtod-round \
- tst-tininess tst-strtod-underflow
+ tst-tininess tst-strtod-underflow tst-tls-atexit
tests-static := tst-secure-getenv
+modules-names = tst-tls-atexit-lib
+
include ../Makeconfig
ifeq ($(build-shared),yes)
@@ -154,3 +156,9 @@ $(objpfx)bug-getcontext: $(link-libm)
$(objpfx)tst-strtod-round: $(link-libm)
$(objpfx)tst-tininess: $(link-libm)
$(objpfx)tst-strtod-underflow: $(link-libm)
+
+tst-tls-atexit-lib.so-no-z-defs = yes
+
+LDFLAGS-tst-tls-atexit = $(common-objpfx)nptl/libpthread.so \
+ $(common-objpfx)dlfcn/libdl.so
+$(objpfx)tst-tls-atexit.out: $(objpfx)tst-tls-atexit-lib.so
diff --git a/stdlib/Versions b/stdlib/Versions
index 250bd5f..f1777df 100644
--- a/stdlib/Versions
+++ b/stdlib/Versions
@@ -106,6 +106,9 @@ libc {
GLIBC_2.17 {
secure_getenv;
}
+ GLIBC_2.18 {
+ __cxa_thread_atexit_impl;
+ }
GLIBC_PRIVATE {
# functions which have an additional interface since they are
# are cancelable.
@@ -114,5 +117,6 @@ libc {
__abort_msg;
# Used from other libraries
__libc_secure_getenv;
+ __call_tls_dtors;
}
}
diff --git a/stdlib/cxa_thread_atexit_impl.c b/stdlib/cxa_thread_atexit_impl.c
new file mode 100644
index 0000000..4f03126
--- /dev/null
+++ b/stdlib/cxa_thread_atexit_impl.c
@@ -0,0 +1,108 @@
+/* Register destructors for C++ TLS variables declared with thread_local.
+ Copyright (C) 2012 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
+ <http://www.gnu.org/licenses/>. */
+
+#include <stdlib.h>
+#include <ldsodefs.h>
+
+typedef void (*dtor_func) (void *);
+
+struct dtor_list
+{
+ dtor_func func;
+ void *obj;
+ struct link_map *map;
+ struct dtor_list *next;
+};
+
+static __thread struct dtor_list *tls_dtor_list;
+static __thread void *dso_handle_cache;
+static __thread struct link_map *lm_cache;
+
+/* Register a destructor for TLS variables declared with the 'thread_local'
+ keyword. This function is only called from code generated by the C++
+ compiler. */
+int
+__cxa_thread_atexit_impl (dtor_func func, void *obj, void *dso_handle)
+{
+ /* Prepend. */
+ struct dtor_list *new = calloc (1, sizeof (struct dtor_list));
+ new->func = func;
+ new->obj = obj;
+ new->next = tls_dtor_list;
+ tls_dtor_list = new;
+
+ /* See if we already encountered the DSO. */
+ __rtld_lock_lock_recursive (GL(dl_load_lock));
+
+ if (__builtin_expect (dso_handle_cache != dso_handle, 0))
+ {
+ ElfW(Addr) caller = (ElfW(Addr)) dso_handle;
+
+ /* If the address is not recognized the call comes from the main
+ program (we hope). */
+ lm_cache = GL(dl_ns)[LM_ID_BASE]._ns_loaded;
+
+ /* Find the highest-addressed object that DSO_HANDLE is not below. */
+ for (Lmid_t ns = 0; ns < GL(dl_nns); ++ns)
+ for (struct link_map *l = GL(dl_ns)[ns]._ns_loaded; l != NULL;
+ l = l->l_next)
+ if (caller >= l->l_map_start && caller < l->l_map_end
+ && (l->l_contiguous || _dl_addr_inside_object (l, caller)))
+ {
+ lm_cache = l;
+ break;
+ }
+
+ }
+ /* A destructor could result in a thread_local construction and the former
+ could have cleared the flag. */
+ if (lm_cache->l_type == lt_loaded && lm_cache->l_tls_dtor_count == 0)
+ lm_cache->l_flags_1 |= DF_1_NODELETE;
+
+ new->map = lm_cache;
+ new->map->l_tls_dtor_count++;
+
+ __rtld_lock_unlock_recursive (GL(dl_load_lock));
+
+ return 0;
+}
+
+/* Call the destructors. This is called either when a thread returns from the
+ initial function or when the process exits via the exit(3) function. */
+void
+__call_tls_dtors (void)
+{
+ while (tls_dtor_list)
+ {
+ struct dtor_list *cur = tls_dtor_list;
+ tls_dtor_list = tls_dtor_list->next;
+
+ cur->func (cur->obj);
+
+ __rtld_lock_lock_recursive (GL(dl_load_lock));
+
+ /* Allow DSO unload if count drops to zero. */
+ cur->map->l_tls_dtor_count--;
+ if (cur->map->l_tls_dtor_count == 0 && cur->map->l_type == lt_loaded)
+ cur->map->l_flags_1 &= ~DF_1_NODELETE;
+
+ __rtld_lock_unlock_recursive (GL(dl_load_lock));
+
+ free (cur);
+ }
+}
diff --git a/stdlib/exit.c b/stdlib/exit.c
index 1ad548f..78cb9f5 100644
--- a/stdlib/exit.c
+++ b/stdlib/exit.c
@@ -25,7 +25,6 @@
#include "set-hooks.h"
DEFINE_HOOK (__libc_atexit, (void))
-
/* Call all functions registered with `atexit' and `on_exit',
in the reverse of the order in which they were registered
perform stdio cleanup, and terminate program execution with STATUS. */
@@ -34,6 +33,9 @@ attribute_hidden
__run_exit_handlers (int status, struct exit_function_list **listp,
bool run_list_atexit)
{
+ /* First, call the TLS destructors. */
+ __call_tls_dtors ();
+
/* We do it this way to handle recursive calls to exit () made by
the functions registered with `atexit' and `on_exit'. We call
everyone on the list and use the status value in the last
diff --git a/stdlib/tst-tls-atexit-lib.c b/stdlib/tst-tls-atexit-lib.c
new file mode 100644
index 0000000..45ce54d
--- /dev/null
+++ b/stdlib/tst-tls-atexit-lib.c
@@ -0,0 +1,37 @@
+/* Verify that DSO is unloaded only if its TLS objects are destroyed - the DSO.
+ Copyright (C) 2012 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
+ <http://www.gnu.org/licenses/>. */
+
+extern void *__dso_handle;
+
+typedef struct
+{
+ void *val;
+} A;
+
+/* We only care about the destructor. */
+void A_dtor (void *obj)
+{
+ ((A *)obj)->val = obj;
+}
+
+void do_foo (void)
+{
+ static __thread A b;
+ __cxa_thread_atexit_impl (A_dtor, &b, __dso_handle);
+}
+
diff --git a/stdlib/tst-tls-atexit.c b/stdlib/tst-tls-atexit.c
new file mode 100644
index 0000000..b7312cb
--- /dev/null
+++ b/stdlib/tst-tls-atexit.c
@@ -0,0 +1,111 @@
+/* Verify that DSO is unloaded only if its TLS objects are destroyed.
+ Copyright (C) 2012 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
+ <http://www.gnu.org/licenses/>. */
+
+/* There are two tests in this test case. The first is implicit where it is
+ assumed that the destructor call on exit of the LOAD function does not
+ segfault. The other is a verification that after the thread has exited, a
+ dlclose will unload the DSO. */
+
+#include <dlfcn.h>
+#include <pthread.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <string.h>
+#include <errno.h>
+
+void *handle;
+pthread_mutex_t m = PTHREAD_MUTEX_INITIALIZER;
+
+void *
+load (void *u)
+{
+ pthread_mutex_lock (&m);
+ handle = dlopen ("$ORIGIN/tst-tls-atexit-lib.so", RTLD_LAZY);
+ if (!handle)
+ {
+ printf ("Unable to load DSO: %s\n", dlerror ());
+ return (void *) (uintptr_t) 1;
+ }
+
+ void (*foo) (void) = (void (*) (void)) dlsym(handle, "do_foo");
+
+ if (!foo)
+ {
+ printf ("Unable to find symbol: %s\n", dlerror ());
+ exit (1);
+ }
+
+ foo ();
+
+ /* This should not unload the DSO. If it does, then the thread exit will
+ result in a segfault. */
+ dlclose (handle);
+ pthread_mutex_unlock (&m);
+
+ return NULL;
+}
+
+int
+main (void)
+{
+ pthread_t t;
+ int ret;
+ void *thr_ret;
+
+ if ((ret = pthread_create (&t, NULL, load, NULL)) != 0)
+ {
+ printf ("pthread_create failed: %s\n", strerror (ret));
+ return 1;
+ }
+
+ if ((ret = pthread_join (t, &thr_ret)) != 0)
+ {
+ printf ("pthread_create failed: %s\n", strerror (ret));
+ return 1;
+ }
+
+ if (thr_ret != NULL)
+ return 1;
+
+ /* Now this should unload the DSO. */
+ dlclose (handle);
+
+ /* Run through our maps and ensure that the DSO is unloaded. */
+ FILE *f = fopen ("/proc/self/maps", "r");
+
+ if (f == NULL)
+ {
+ perror ("Failed to open /proc/self/maps");
+ fprintf (stderr, "Skipping verification of DSO unload\n");
+ return 0;
+ }
+
+ char *line = NULL;
+ size_t s = 0;
+ while (getline (&line, &s, f) > 0)
+ {
+ if (strstr (line, "tst-tls-atexit-lib.so"))
+ {
+ printf ("DSO not unloaded yet:\n%s", line);
+ return 1;
+ }
+ }
+ free (line);
+
+ return 0;
+}
diff --git a/sysdeps/unix/sysv/linux/i386/nptl/libc.abilist b/sysdeps/unix/sysv/linux/i386/nptl/libc.abilist
index 67d5929..3cb314d 100644
--- a/sysdeps/unix/sysv/linux/i386/nptl/libc.abilist
+++ b/sysdeps/unix/sysv/linux/i386/nptl/libc.abilist
@@ -1819,6 +1819,9 @@ GLIBC_2.17
clock_nanosleep F
clock_settime F
secure_getenv F
+GLIBC_2.18
+ GLIBC_2.18 A
+ __cxa_thread_atexit_impl F
GLIBC_2.2
GLIBC_2.2 A
_IO_adjust_wcolumn F
diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/nptl/libc.abilist b/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/nptl/libc.abilist
index 8e45958..f27b48b 100644
--- a/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/nptl/libc.abilist
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/nptl/libc.abilist
@@ -1781,6 +1781,9 @@ GLIBC_2.17
clock_nanosleep F
clock_settime F
secure_getenv F
+GLIBC_2.18
+ GLIBC_2.18 A
+ __cxa_thread_atexit_impl F
GLIBC_2.2
GLIBC_2.2 A
_IO_adjust_wcolumn F
diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc64/nptl/libc.abilist b/sysdeps/unix/sysv/linux/powerpc/powerpc64/nptl/libc.abilist
index 8eaaccd..195b587 100644
--- a/sysdeps/unix/sysv/linux/powerpc/powerpc64/nptl/libc.abilist
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc64/nptl/libc.abilist
@@ -87,6 +87,9 @@ GLIBC_2.17
clock_nanosleep F
clock_settime F
secure_getenv F
+GLIBC_2.18
+ GLIBC_2.18 A
+ __cxa_thread_atexit_impl F
GLIBC_2.3
GLIBC_2.3 A
_Exit F
diff --git a/sysdeps/unix/sysv/linux/s390/s390-32/nptl/libc.abilist b/sysdeps/unix/sysv/linux/s390/s390-32/nptl/libc.abilist
index d9914ff..b6256d5 100644
--- a/sysdeps/unix/sysv/linux/s390/s390-32/nptl/libc.abilist
+++ b/sysdeps/unix/sysv/linux/s390/s390-32/nptl/libc.abilist
@@ -1771,6 +1771,9 @@ GLIBC_2.17
clock_nanosleep F
clock_settime F
secure_getenv F
+GLIBC_2.18
+ GLIBC_2.18 A
+ __cxa_thread_atexit_impl F
GLIBC_2.2
GLIBC_2.2 A
_IO_adjust_wcolumn F
diff --git a/sysdeps/unix/sysv/linux/s390/s390-64/nptl/libc.abilist b/sysdeps/unix/sysv/linux/s390/s390-64/nptl/libc.abilist
index ef1ead3..265f66d 100644
--- a/sysdeps/unix/sysv/linux/s390/s390-64/nptl/libc.abilist
+++ b/sysdeps/unix/sysv/linux/s390/s390-64/nptl/libc.abilist
@@ -92,6 +92,9 @@ GLIBC_2.17
clock_nanosleep F
clock_settime F
secure_getenv F
+GLIBC_2.18
+ GLIBC_2.18 A
+ __cxa_thread_atexit_impl F
GLIBC_2.2
GLIBC_2.2 A
_Exit F
diff --git a/sysdeps/unix/sysv/linux/sh/nptl/libc.abilist b/sysdeps/unix/sysv/linux/sh/nptl/libc.abilist
index 733b550..a653292 100644
--- a/sysdeps/unix/sysv/linux/sh/nptl/libc.abilist
+++ b/sysdeps/unix/sysv/linux/sh/nptl/libc.abilist
@@ -92,6 +92,9 @@ GLIBC_2.17
clock_nanosleep F
clock_settime F
secure_getenv F
+GLIBC_2.18
+ GLIBC_2.18 A
+ __cxa_thread_atexit_impl F
GLIBC_2.2
GLIBC_2.2 A
_Exit F
diff --git a/sysdeps/unix/sysv/linux/sparc/sparc32/nptl/libc.abilist b/sysdeps/unix/sysv/linux/sparc/sparc32/nptl/libc.abilist
index 3a96ea8..9defbdf 100644
--- a/sysdeps/unix/sysv/linux/sparc/sparc32/nptl/libc.abilist
+++ b/sysdeps/unix/sysv/linux/sparc/sparc32/nptl/libc.abilist
@@ -1776,6 +1776,9 @@ GLIBC_2.17
clock_nanosleep F
clock_settime F
secure_getenv F
+GLIBC_2.18
+ GLIBC_2.18 A
+ __cxa_thread_atexit_impl F
GLIBC_2.2
GLIBC_2.2 A
_IO_adjust_wcolumn F
diff --git a/sysdeps/unix/sysv/linux/sparc/sparc64/nptl/libc.abilist b/sysdeps/unix/sysv/linux/sparc/sparc64/nptl/libc.abilist
index aa892b8..35987fa 100644
--- a/sysdeps/unix/sysv/linux/sparc/sparc64/nptl/libc.abilist
+++ b/sysdeps/unix/sysv/linux/sparc/sparc64/nptl/libc.abilist
@@ -97,6 +97,9 @@ GLIBC_2.17
clock_nanosleep F
clock_settime F
secure_getenv F
+GLIBC_2.18
+ GLIBC_2.18 A
+ __cxa_thread_atexit_impl F
GLIBC_2.2
GLIBC_2.2 A
_Exit F
diff --git a/sysdeps/unix/sysv/linux/x86_64/64/nptl/libc.abilist b/sysdeps/unix/sysv/linux/x86_64/64/nptl/libc.abilist
index a42d424..914b590 100644
--- a/sysdeps/unix/sysv/linux/x86_64/64/nptl/libc.abilist
+++ b/sysdeps/unix/sysv/linux/x86_64/64/nptl/libc.abilist
@@ -88,6 +88,9 @@ GLIBC_2.17
clock_nanosleep F
clock_settime F
secure_getenv F
+GLIBC_2.18
+ GLIBC_2.18 A
+ __cxa_thread_atexit_impl F
GLIBC_2.2.5
GLIBC_2.2.5 A
_Exit F
diff --git a/sysdeps/unix/sysv/linux/x86_64/x32/nptl/libc.abilist b/sysdeps/unix/sysv/linux/x86_64/x32/nptl/libc.abilist
index 108b80f..0f64c8d 100644
--- a/sysdeps/unix/sysv/linux/x86_64/x32/nptl/libc.abilist
+++ b/sysdeps/unix/sysv/linux/x86_64/x32/nptl/libc.abilist
@@ -2086,3 +2086,6 @@ GLIBC_2.17
clock_nanosleep F
clock_settime F
secure_getenv F
+GLIBC_2.18
+ GLIBC_2.18 A
+ __cxa_thread_atexit_impl F