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Diffstat (limited to 'sysdeps/x86_64/dl-tls.c')
-rw-r--r--sysdeps/x86_64/dl-tls.c53
1 files changed, 53 insertions, 0 deletions
diff --git a/sysdeps/x86_64/dl-tls.c b/sysdeps/x86_64/dl-tls.c
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+++ b/sysdeps/x86_64/dl-tls.c
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+/* Thread-local storage handling in the ELF dynamic linker. x86-64 version.
+ Copyright (C) 2017-2018 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/>. */
+
+#ifdef SHARED
+/* Work around GCC PR58066, due to which __tls_get_addr may be called
+ with an unaligned stack. The compat implementation is in
+ tls_get_addr-compat.S. */
+
+# include <dl-tls.h>
+
+/* Define __tls_get_addr within elf/dl-tls.c under a different
+ name. */
+extern __typeof__ (__tls_get_addr) ___tls_get_addr;
+
+# define __tls_get_addr ___tls_get_addr
+# include <elf/dl-tls.c>
+# undef __tls_get_addr
+
+hidden_ver (___tls_get_addr, __tls_get_addr)
+
+/* Only handle slow paths for __tls_get_addr. */
+attribute_hidden
+void *
+__tls_get_addr_slow (GET_ADDR_ARGS)
+{
+ dtv_t *dtv = THREAD_DTV ();
+
+ if (__glibc_unlikely (dtv[0].counter != GL(dl_tls_generation)))
+ return update_get_addr (GET_ADDR_PARAM);
+
+ return tls_get_addr_tail (GET_ADDR_PARAM, dtv, NULL);
+}
+#else
+
+/* No compatibility symbol needed. */
+# include <elf/dl-tls.c>
+
+#endif