[BZ #17075] ARM: Fix immediate calculation of R_ARM_TLS_DESC

This fixes the calculation of R_ARM_TLS_DESC relocations for lazy global
symbol references, i.e. created with `-z lazy' in effect with the static
linker, where immediate resolution is requested with LD_BIND_NOW.

ChangeLog

@@ -1,3 +1,31 @@
+2014-06-20  Maciej W. Rozycki  <macro@codesourcery.com>
+
+	[BZ #17075]
+	* sysdeps/arm/dl-machine.h (elf_machine_rel) <R_ARM_TLS_DESC>:
+	Fix calculation of the symbol's value.
+	* sysdeps/arm/tst-armtlsdescloc.c: New file.
+	* sysdeps/arm/tst-armtlsdesclocmod.c: New file.
+	* sysdeps/arm/tst-armtlsdescextnow.c: New file.
+	* sysdeps/arm/tst-armtlsdescextlazymod.c: New file.
+	* sysdeps/arm/tst-armtlsdescextlazy.c: New file.
+	* sysdeps/arm/tst-armtlsdescextnowmod.c: New file.
+	* sysdeps/arm/Makefile (tests): Add `tst-armtlsdesc',
+	`tst-armtlsdescextnow' and `tst-armtlsdescextlazy'.
+	(modules-names): Add `tst-armtlsdescmod',
+	`tst-armtlsdescextlazymod' and `tst-armtlsdescextnowmod'.
+	(CPPFLAGS-tst-armtlsdescextnowmod.c): New variable.
+	(CPPFLAGS-tst-armtlsdescextlazymod.c): Likewise.
+	(CFLAGS-tst-armtlsdesclocmod.c): Likewise.
+	(CFLAGS-tst-armtlsdescextnowmod.c): Likewise.
+	(CFLAGS-tst-armtlsdescextlazymod.c): Likewise.
+	(LDFLAGS-tst-armtlsdescextnowmod.so): Likewise.
+	($(objpfx)tst-armtlsdescloc): New dependency.
+	($(objpfx)tst-armtlsdescextnow): Likewise.
+	($(objpfx)tst-armtlsdescextlazy): Likewise.
+	* sysdeps/arm/configure.ac: Add a check for tools' GNU descriptor
+	TLS scheme support.
+	* sysdeps/arm/configure: Regenerate.
+
 2014-06-20  Joseph Myers  <joseph@codesourcery.com>
 
 	* include/fcntl.h (__atfct_seterrno): Remove prototype.

NEWS

@@ -20,7 +20,7 @@ Version 2.20
   16854, 16876, 16877, 16878, 16882, 16885, 16888, 16890, 16912, 16915,
   16916, 16917, 16922, 16927, 16928, 16932, 16943, 16958, 16965, 16966,
   16967, 16977, 16978, 16984, 16990, 16996, 17009, 17022, 17031, 17042,
-  17048, 17058, 17062, 17069.
+  17048, 17058, 17062, 17069, 17075.
 
 * Optimized strchr implementation for AArch64.  Contributed by ARM Ltd.
 

sysdeps/arm/Makefile

@@ -11,6 +11,26 @@ $(objpfx)libgcc-stubs.a: $(objpfx)aeabi_unwind_cpp_pr1.os
 	$(build-extra-lib)
 
 lib-noranlib: $(objpfx)libgcc-stubs.a
+
+ifeq ($(build-shared),yes)
+ifeq ($(have-arm-tls-desc),yes)
+tests += tst-armtlsdescloc tst-armtlsdescextnow tst-armtlsdescextlazy
+modules-names += tst-armtlsdesclocmod
+modules-names += tst-armtlsdescextlazymod tst-armtlsdescextnowmod
+CPPFLAGS-tst-armtlsdescextnowmod.c += -Dstatic=
+CPPFLAGS-tst-armtlsdescextlazymod.c += -Dstatic=
+CFLAGS-tst-armtlsdesclocmod.c += -mtls-dialect=gnu2
+CFLAGS-tst-armtlsdescextnowmod.c += -mtls-dialect=gnu2
+CFLAGS-tst-armtlsdescextlazymod.c += -mtls-dialect=gnu2
+LDFLAGS-tst-armtlsdescextnowmod.so += -Wl,-z,now
+tst-armtlsdescloc-ENV = LD_BIND_NOW=1
+tst-armtlsdescextnow-ENV = LD_BIND_NOW=1
+tst-armtlsdescextlazy-ENV = LD_BIND_NOW=1
+$(objpfx)tst-armtlsdescloc: $(objpfx)tst-armtlsdesclocmod.so
+$(objpfx)tst-armtlsdescextnow: $(objpfx)tst-armtlsdescextnowmod.so
+$(objpfx)tst-armtlsdescextlazy: $(objpfx)tst-armtlsdescextlazymod.so
+endif
+endif
 endif
 
 ifeq ($(subdir),csu)

sysdeps/arm/configure

@@ -203,3 +203,39 @@ else
   config_vars="$config_vars
 default-abi = soft"
 fi
+
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking whether the build tools support the GNU descriptor TLS scheme" >&5
+$as_echo_n "checking whether the build tools support the GNU descriptor TLS scheme... " >&6; }
+if ${libc_cv_arm_tls_desc+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+  old_CFLAGS="$CFLAGS"
+  CFLAGS="$CFLAGS -mtls-dialect=gnu2"
+  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+asm (".word\tfoo(tlsdesc)");
+int
+main ()
+{
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+  libc_cv_arm_tls_desc=yes
+else
+  libc_cv_arm_tls_desc=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+  CFLAGS="$old_CFLAGS"
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $libc_cv_arm_tls_desc" >&5
+$as_echo "$libc_cv_arm_tls_desc" >&6; }
+if test $libc_cv_arm_tls_desc = yes; then
+  config_vars="$config_vars
+have-arm-tls-desc = yes"
+else
+  config_vars="$config_vars
+have-arm-tls-desc = no"
+fi

sysdeps/arm/configure.ac

@@ -44,3 +44,16 @@ if test $libc_cv_arm_pcs_vfp = yes; then
 else
   LIBC_CONFIG_VAR([default-abi], [soft])
 fi
+
+AC_CACHE_CHECK([whether the build tools support the GNU descriptor TLS scheme],
+  [libc_cv_arm_tls_desc],
+  [old_CFLAGS="$CFLAGS"
+  CFLAGS="$CFLAGS -mtls-dialect=gnu2"
+  AC_COMPILE_IFELSE([AC_LANG_PROGRAM([asm (".word\tfoo(tlsdesc)");], [])],
+    [libc_cv_arm_tls_desc=yes], [libc_cv_arm_tls_desc=no])
+  CFLAGS="$old_CFLAGS"])
+if test $libc_cv_arm_tls_desc = yes; then
+  LIBC_CONFIG_VAR([have-arm-tls-desc], [yes])
+else
+  LIBC_CONFIG_VAR([have-arm-tls-desc], [no])
+fi

sysdeps/arm/dl-machine.h

@@ -452,7 +452,10 @@ elf_machine_rel (struct link_map *map, const Elf32_Rel *reloc,
 	    else
 # endif
 	      {
-		value = sym->st_value + td->argument.value;
+		if (ELF32_R_SYM (reloc->r_info) == STN_UNDEF)
+		  value = td->argument.value;
+		else
+		  value = sym->st_value;
 
 # ifndef RTLD_BOOTSTRAP
 #  ifndef SHARED

sysdeps/arm/tst-armtlsdescextlazy.c

@@ -0,0 +1 @@
+#include "tst-armtlsdescloc.c"

sysdeps/arm/tst-armtlsdescextlazymod.c

@@ -0,0 +1 @@
+#include "tst-armtlsdesclocmod.c"

sysdeps/arm/tst-armtlsdescextnow.c

@@ -0,0 +1 @@
+#include "tst-armtlsdescloc.c"

sysdeps/arm/tst-armtlsdescextnowmod.c

@@ -0,0 +1 @@
+#include "tst-armtlsdesclocmod.c"

sysdeps/arm/tst-armtlsdescloc.c

@@ -0,0 +1,28 @@
+/* ARM immediate binding GNU TLS descriptor relocation test.
+   Copyright (C) 2014 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/>.  */
+
+int getfoo (void);
+
+int
+do_test (void)
+{
+  return getfoo ();
+}
+
+#define TEST_FUNCTION do_test ()
+#include "../test-skeleton.c"

sysdeps/arm/tst-armtlsdesclocmod.c

@@ -0,0 +1,44 @@
+/* DSO used for ARM immediate binding GNU TLS descriptor relocation test.
+   Copyright (C) 2014 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/>.  */
+
+static int __thread bar = 1;
+static int __thread foo;
+
+int
+getfoo (void)
+{
+  return foo;
+}
+
+void
+setfoo (int i)
+{
+  foo = 1;
+}
+
+int
+getbar (void)
+{
+  return bar;
+}
+
+void
+setbar (int i)
+{
+  bar = 1;
+}