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commit 627f5ede70d70c77bdaf857db07404e8bf7f60af
Author: Florian Weimer <fweimer@redhat.com>
Date: Thu Dec 9 17:57:11 2021 +0100
Remove TLS_TCB_ALIGN and TLS_INIT_TCB_ALIGN
TLS_INIT_TCB_ALIGN is not actually used. TLS_TCB_ALIGN was likely
introduced to support a configuration where the thread pointer
has not the same alignment as THREAD_SELF. Only ia64 seems to use
that, but for the stack/pointer guard, not for storing tcbhead_t.
Some ports use TLS_TCB_OFFSET and TLS_PRE_TCB_SIZE to shift
the thread pointer, potentially landing in a different residue class
modulo the alignment, but the changes should not impact that.
In general, given that TLS variables have their own alignment
requirements, having different alignment for the (unshifted) thread
pointer and struct pthread would potentially result in dynamic
offsets, leading to more complexity.
hppa had different values before: __alignof__ (tcbhead_t), which
seems to be 4, and __alignof__ (struct pthread), which was 8
(old default) and is now 32. However, it defines THREAD_SELF as:
/* Return the thread descriptor for the current thread. */
# define THREAD_SELF \
({ struct pthread *__self; \
__self = __get_cr27(); \
__self - 1; \
})
So the thread pointer points after struct pthread (hence __self - 1),
and they have to have the same alignment on hppa as well.
Similarly, on ia64, the definitions were different. We have:
# define TLS_PRE_TCB_SIZE \
(sizeof (struct pthread) \
+ (PTHREAD_STRUCT_END_PADDING < 2 * sizeof (uintptr_t) \
? ((2 * sizeof (uintptr_t) + __alignof__ (struct pthread) - 1) \
& ~(__alignof__ (struct pthread) - 1)) \
: 0))
# define THREAD_SELF \
((struct pthread *) ((char *) __thread_self - TLS_PRE_TCB_SIZE))
And TLS_PRE_TCB_SIZE is a multiple of the struct pthread alignment
(confirmed by the new _Static_assert in sysdeps/ia64/libc-tls.c).
On m68k, we have a larger gap between tcbhead_t and struct pthread.
But as far as I can tell, the port is fine with that. The definition
of TCB_OFFSET is sufficient to handle the shifted TCB scenario.
This fixes commit 23c77f60181eb549f11ec2f913b4270af29eee38
("nptl: Increase default TCB alignment to 32").
Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
diff --git a/csu/libc-tls.c b/csu/libc-tls.c
index 5515204863218163..d83e69f6257ae981 100644
--- a/csu/libc-tls.c
+++ b/csu/libc-tls.c
@@ -24,6 +24,7 @@
#include <stdio.h>
#include <sys/param.h>
#include <array_length.h>
+#include <pthreadP.h>
#ifdef SHARED
#error makefile bug, this file is for static only
@@ -89,7 +90,7 @@ init_static_tls (size_t memsz, size_t align)
{
/* That is the size of the TLS memory for this object. */
GL(dl_tls_static_size) = roundup (memsz + GLRO(dl_tls_static_surplus),
- TLS_TCB_ALIGN);
+ TCB_ALIGNMENT);
#if TLS_TCB_AT_TP
GL(dl_tls_static_size) += TLS_TCB_SIZE;
#endif
@@ -214,5 +215,5 @@ __libc_setup_tls (void)
memsz += tcb_offset;
#endif
- init_static_tls (memsz, MAX (TLS_TCB_ALIGN, max_align));
+ init_static_tls (memsz, MAX (TCB_ALIGNMENT, max_align));
}
diff --git a/elf/dl-tls.c b/elf/dl-tls.c
index 40263cf586e74c64..e2012d0cd515103b 100644
--- a/elf/dl-tls.c
+++ b/elf/dl-tls.c
@@ -219,7 +219,7 @@ _dl_count_modids (void)
void
_dl_determine_tlsoffset (void)
{
- size_t max_align = TLS_TCB_ALIGN;
+ size_t max_align = TCB_ALIGNMENT;
size_t freetop = 0;
size_t freebottom = 0;
@@ -350,7 +350,7 @@ _dl_determine_tlsoffset (void)
GL(dl_tls_static_used) = offset;
GLRO (dl_tls_static_size) = roundup (offset + GLRO(dl_tls_static_surplus),
- TLS_TCB_ALIGN);
+ TCB_ALIGNMENT);
#else
# error "Either TLS_TCB_AT_TP or TLS_DTV_AT_TP must be defined"
#endif
diff --git a/sysdeps/aarch64/nptl/tls.h b/sysdeps/aarch64/nptl/tls.h
index cd9abb5d1d073593..75c469d51b532a89 100644
--- a/sysdeps/aarch64/nptl/tls.h
+++ b/sysdeps/aarch64/nptl/tls.h
@@ -52,18 +52,12 @@ typedef struct
/* This is the size of the initial TCB. */
# define TLS_INIT_TCB_SIZE sizeof (tcbhead_t)
-/* Alignment requirements for the initial TCB. */
-# define TLS_INIT_TCB_ALIGN __alignof__ (struct pthread)
-
/* This is the size of the TCB. */
# define TLS_TCB_SIZE sizeof (tcbhead_t)
/* This is the size we need before TCB. */
# define TLS_PRE_TCB_SIZE sizeof (struct pthread)
-/* Alignment requirements for the TCB. */
-# define TLS_TCB_ALIGN __alignof__ (struct pthread)
-
/* Install the dtv pointer. The pointer passed is to the element with
index -1 which contain the length. */
# define INSTALL_DTV(tcbp, dtvp) \
diff --git a/sysdeps/alpha/nptl/tls.h b/sysdeps/alpha/nptl/tls.h
index 5f4843b28e7f1ad1..c0b6c93891546480 100644
--- a/sysdeps/alpha/nptl/tls.h
+++ b/sysdeps/alpha/nptl/tls.h
@@ -46,18 +46,12 @@ typedef struct
/* This is the size of the initial TCB. */
# define TLS_INIT_TCB_SIZE sizeof (tcbhead_t)
-/* Alignment requirements for the initial TCB. */
-# define TLS_INIT_TCB_ALIGN 16
-
/* This is the size of the TCB. */
# define TLS_TCB_SIZE sizeof (tcbhead_t)
/* This is the size we need before TCB. */
# define TLS_PRE_TCB_SIZE sizeof (struct pthread)
-/* Alignment requirements for the TCB. */
-# define TLS_TCB_ALIGN 16
-
/* Install the dtv pointer. The pointer passed is to the element with
index -1 which contain the length. */
# define INSTALL_DTV(tcbp, dtvp) \
diff --git a/sysdeps/arc/nptl/tls.h b/sysdeps/arc/nptl/tls.h
index d9ada2f38089e6cd..d5d282297d12ec98 100644
--- a/sysdeps/arc/nptl/tls.h
+++ b/sysdeps/arc/nptl/tls.h
@@ -48,17 +48,11 @@ typedef struct
/* This is the size of the initial TCB. */
# define TLS_INIT_TCB_SIZE sizeof (tcbhead_t)
-/* Alignment requirements for the initial TCB. */
-# define TLS_INIT_TCB_ALIGN __alignof__ (struct pthread)
-
/* This is the size of the TCB. */
#ifndef TLS_TCB_SIZE
# define TLS_TCB_SIZE sizeof (tcbhead_t)
#endif
-/* Alignment requirements for the TCB. */
-# define TLS_TCB_ALIGN __alignof__ (struct pthread)
-
/* This is the size we need before TCB. */
# define TLS_PRE_TCB_SIZE sizeof (struct pthread)
diff --git a/sysdeps/arm/nptl/tls.h b/sysdeps/arm/nptl/tls.h
index 354aae3318291395..8475c66588f99cae 100644
--- a/sysdeps/arm/nptl/tls.h
+++ b/sysdeps/arm/nptl/tls.h
@@ -50,18 +50,12 @@ typedef struct
/* This is the size of the initial TCB. */
# define TLS_INIT_TCB_SIZE sizeof (tcbhead_t)
-/* Alignment requirements for the initial TCB. */
-# define TLS_INIT_TCB_ALIGN 16
-
/* This is the size of the TCB. */
# define TLS_TCB_SIZE sizeof (tcbhead_t)
/* This is the size we need before TCB. */
# define TLS_PRE_TCB_SIZE sizeof (struct pthread)
-/* Alignment requirements for the TCB. */
-# define TLS_TCB_ALIGN 16
-
/* Install the dtv pointer. The pointer passed is to the element with
index -1 which contain the length. */
# define INSTALL_DTV(tcbp, dtvp) \
diff --git a/sysdeps/csky/nptl/tls.h b/sysdeps/csky/nptl/tls.h
index f3fa3fcb02748776..e81d4552d27e0378 100644
--- a/sysdeps/csky/nptl/tls.h
+++ b/sysdeps/csky/nptl/tls.h
@@ -61,15 +61,9 @@ typedef struct
/* This is the size of the initial TCB. */
# define TLS_INIT_TCB_SIZE sizeof (tcbhead_t)
-/* Alignment requirements for the initial TCB. */
-# define TLS_INIT_TCB_ALIGN 8
-
/* This is the size of the TCB. */
# define TLS_TCB_SIZE sizeof (tcbhead_t)
-/* Alignment requirements for the TCB. */
-# define TLS_TCB_ALIGN 8
-
/* This is the size we need before TCB. */
# define TLS_PRE_TCB_SIZE sizeof (struct pthread)
diff --git a/sysdeps/generic/tls.h b/sysdeps/generic/tls.h
index e86d70e6cebba5c8..9214ed39b6383e8c 100644
--- a/sysdeps/generic/tls.h
+++ b/sysdeps/generic/tls.h
@@ -19,6 +19,11 @@
/* An architecture-specific version of this file has to defined a
number of symbols:
+ TCB_ALIGNMENT
+
+ Alignment of THREAD_SELF (struct pthread *) and the thread
+ pointer.
+
TLS_TCB_AT_TP or TLS_DTV_AT_TP
The presence of one of these symbols signals which variant of
@@ -43,15 +48,6 @@
dynamic linker itself. There are no threads in use at that time.
- TLS_TCB_ALIGN
-
- Alignment requirements for the TCB structure.
-
- TLS_INIT_TCB_ALIGN
-
- Similarly, but for the structure used at startup time.
-
-
INSTALL_DTV(tcb, init_dtv)
This macro must install the given initial DTV into the thread control
diff --git a/sysdeps/hppa/nptl/tls.h b/sysdeps/hppa/nptl/tls.h
index f0e274c45fb5e91e..88a6b902c0b7e2fd 100644
--- a/sysdeps/hppa/nptl/tls.h
+++ b/sysdeps/hppa/nptl/tls.h
@@ -52,15 +52,9 @@ typedef struct
/* This is the size of the initial TCB. */
# define TLS_INIT_TCB_SIZE sizeof (tcbhead_t)
-/* Alignment requirements for the initial TCB. */
-# define TLS_INIT_TCB_ALIGN __alignof__ (tcbhead_t)
-
/* This is the size of the TCB. */
# define TLS_TCB_SIZE sizeof (tcbhead_t)
-/* Alignment requirements for the TCB. */
-# define TLS_TCB_ALIGN __alignof__ (struct pthread)
-
/* This is the size we need before TCB */
# define TLS_PRE_TCB_SIZE sizeof (struct pthread)
diff --git a/sysdeps/i386/nptl/tls.h b/sysdeps/i386/nptl/tls.h
index 111c9ee59df30bc3..06ab9784a5358b0b 100644
--- a/sysdeps/i386/nptl/tls.h
+++ b/sysdeps/i386/nptl/tls.h
@@ -102,15 +102,9 @@ union user_desc_init
struct pthread even when not linked with -lpthread. */
# define TLS_INIT_TCB_SIZE sizeof (struct pthread)
-/* Alignment requirements for the initial TCB. */
-# define TLS_INIT_TCB_ALIGN __alignof__ (struct pthread)
-
/* This is the size of the TCB. */
# define TLS_TCB_SIZE sizeof (struct pthread)
-/* Alignment requirements for the TCB. */
-# define TLS_TCB_ALIGN __alignof__ (struct pthread)
-
/* The TCB can have any size and the memory following the address the
thread pointer points to is unspecified. Allocate the TCB there. */
# define TLS_TCB_AT_TP 1
diff --git a/sysdeps/ia64/libc-tls.c b/sysdeps/ia64/libc-tls.c
index a01edceab36d375e..ede1e8f463b135b4 100644
--- a/sysdeps/ia64/libc-tls.c
+++ b/sysdeps/ia64/libc-tls.c
@@ -18,6 +18,9 @@
#include <csu/libc-tls.c>
+_Static_assert (TLS_PRE_TCB_SIZE % __alignof (struct pthread) == 0,
+ "__thread_self and THREAD_SELF have same alignment");
+
/* On IA-64, as it lacks linker optimizations, __tls_get_addr can be
called even in statically linked binaries.
In this case module must be always 1 and PT_TLS segment
diff --git a/sysdeps/ia64/nptl/tls.h b/sysdeps/ia64/nptl/tls.h
index 26fe555cb4b5e164..ca8f1280aeeed3d5 100644
--- a/sysdeps/ia64/nptl/tls.h
+++ b/sysdeps/ia64/nptl/tls.h
@@ -53,9 +53,6 @@ register struct pthread *__thread_self __asm__("r13");
/* This is the size of the initial TCB. */
# define TLS_INIT_TCB_SIZE sizeof (tcbhead_t)
-/* Alignment requirements for the initial TCB. */
-# define TLS_INIT_TCB_ALIGN __alignof__ (tcbhead_t)
-
/* This is the size of the TCB. */
# define TLS_TCB_SIZE sizeof (tcbhead_t)
@@ -70,9 +67,6 @@ register struct pthread *__thread_self __asm__("r13");
& ~(__alignof__ (struct pthread) - 1)) \
: 0))
-/* Alignment requirements for the TCB. */
-# define TLS_TCB_ALIGN __alignof__ (struct pthread)
-
/* The DTV is allocated at the TP; the TCB is placed elsewhere. */
# define TLS_DTV_AT_TP 1
# define TLS_TCB_AT_TP 0
diff --git a/sysdeps/m68k/nptl/tls.h b/sysdeps/m68k/nptl/tls.h
index 9f562c38288df200..b88ef0c9c74ae0b0 100644
--- a/sysdeps/m68k/nptl/tls.h
+++ b/sysdeps/m68k/nptl/tls.h
@@ -54,20 +54,15 @@ typedef struct
pointer, we don't need this. */
# define TLS_INIT_TCB_SIZE 0
-/* Alignment requirements for the initial TCB. */
-# define TLS_INIT_TCB_ALIGN __alignof__ (struct pthread)
-
/* This is the size of the TCB. Because our TCB is before the thread
pointer, we don't need this. */
# define TLS_TCB_SIZE 0
-/* Alignment requirements for the TCB. */
-# define TLS_TCB_ALIGN __alignof__ (struct pthread)
-
/* This is the size we need before TCB - actually, it includes the TCB. */
# define TLS_PRE_TCB_SIZE \
(sizeof (struct pthread) \
- + ((sizeof (tcbhead_t) + TLS_TCB_ALIGN - 1) & ~(TLS_TCB_ALIGN - 1)))
+ + ((sizeof (tcbhead_t) + __alignof (struct pthread) - 1) \
+ & ~(__alignof (struct pthread) - 1)))
/* The thread pointer (TP) points to the end of the
TCB + 0x7000, as for PowerPC and MIPS. This implies that TCB address is
diff --git a/sysdeps/mach/hurd/tls.h b/sysdeps/mach/hurd/tls.h
index f83956d3d7ca4f9f..773a2a0c36d5d57d 100644
--- a/sysdeps/mach/hurd/tls.h
+++ b/sysdeps/mach/hurd/tls.h
@@ -29,20 +29,12 @@
# include <mach.h>
# include <atomic.h>
-
/* This is the size of the initial TCB. */
# define TLS_INIT_TCB_SIZE sizeof (tcbhead_t)
-/* Alignment requirements for the initial TCB. */
-# define TLS_INIT_TCB_ALIGN __alignof__ (tcbhead_t)
-
/* This is the size of the TCB. */
# define TLS_TCB_SIZE TLS_INIT_TCB_SIZE /* XXX */
-/* Alignment requirements for the TCB. */
-# define TLS_TCB_ALIGN TLS_INIT_TCB_ALIGN /* XXX */
-
-
/* Install the dtv pointer. The pointer passed is to the element with
index -1 which contain the length. */
# define INSTALL_DTV(descr, dtvp) \
diff --git a/sysdeps/microblaze/nptl/tls.h b/sysdeps/microblaze/nptl/tls.h
index bfa6efa78049bb2d..b69d7b4f28f3b757 100644
--- a/sysdeps/microblaze/nptl/tls.h
+++ b/sysdeps/microblaze/nptl/tls.h
@@ -56,18 +56,12 @@ typedef struct
/* This is the size of the initial TCB. */
# define TLS_INIT_TCB_SIZE sizeof (tcbhead_t)
-/* Alignment requirements for the initial TCB. */
-# define TLS_INIT_TCB_ALIGN __alignof__ (tcbhead_t)
-
/* This is the size of the TCB. */
# define TLS_TCB_SIZE sizeof (tcbhead_t)
/* This is the size we need before TCB. */
# define TLS_PRE_TCB_SIZE sizeof (struct pthread)
-/* Alignment requirements for the TCB. */
-# define TLS_TCB_ALIGN __alignof__ (struct pthread)
-
/* Install the dtv pointer. The pointer passed is to the element with
index -1 which contain the length. */
# define INSTALL_DTV(tcbp, dtvp) \
diff --git a/sysdeps/mips/nptl/tls.h b/sysdeps/mips/nptl/tls.h
index ef99aa646c898e76..6ccaf9804a68634a 100644
--- a/sysdeps/mips/nptl/tls.h
+++ b/sysdeps/mips/nptl/tls.h
@@ -83,20 +83,15 @@ typedef struct
pointer, we don't need this. */
# define TLS_INIT_TCB_SIZE 0
-/* Alignment requirements for the initial TCB. */
-# define TLS_INIT_TCB_ALIGN __alignof__ (struct pthread)
-
/* This is the size of the TCB. Because our TCB is before the thread
pointer, we don't need this. */
# define TLS_TCB_SIZE 0
-/* Alignment requirements for the TCB. */
-# define TLS_TCB_ALIGN __alignof__ (struct pthread)
-
/* This is the size we need before TCB - actually, it includes the TCB. */
# define TLS_PRE_TCB_SIZE \
(sizeof (struct pthread) \
- + ((sizeof (tcbhead_t) + TLS_TCB_ALIGN - 1) & ~(TLS_TCB_ALIGN - 1)))
+ + ((sizeof (tcbhead_t) + __alignof (struct pthread) - 1) \
+ & ~(__alignof (struct pthread) - 1)))
/* The thread pointer (in hardware register $29) points to the end of
the TCB + 0x7000, as for PowerPC. The pthread_descr structure is
diff --git a/sysdeps/nios2/nptl/tls.h b/sysdeps/nios2/nptl/tls.h
index 7110cfccad7131f4..6ab6bd27b00a70ee 100644
--- a/sysdeps/nios2/nptl/tls.h
+++ b/sysdeps/nios2/nptl/tls.h
@@ -59,20 +59,15 @@ register struct pthread *__thread_self __asm__("r23");
pointer, we don't need this. */
# define TLS_INIT_TCB_SIZE 0
-/* Alignment requirements for the initial TCB. */
-# define TLS_INIT_TCB_ALIGN __alignof__ (struct pthread)
-
/* This is the size of the TCB. Because our TCB is before the thread
pointer, we don't need this. */
# define TLS_TCB_SIZE 0
-/* Alignment requirements for the TCB. */
-# define TLS_TCB_ALIGN __alignof__ (struct pthread)
-
/* This is the size we need before TCB - actually, it includes the TCB. */
# define TLS_PRE_TCB_SIZE \
(sizeof (struct pthread) \
- + ((sizeof (tcbhead_t) + TLS_TCB_ALIGN - 1) & ~(TLS_TCB_ALIGN - 1)))
+ + ((sizeof (tcbhead_t) + __alignof (struct pthread) - 1) \
+ & ~(__alignof (struct pthread) - 1)))
/* The thread pointer (in hardware register r23) points to the end of
the TCB + 0x7000, as for PowerPC and MIPS. */
diff --git a/sysdeps/powerpc/nptl/tls.h b/sysdeps/powerpc/nptl/tls.h
index 110d085d30c86302..e194b334216eaa02 100644
--- a/sysdeps/powerpc/nptl/tls.h
+++ b/sysdeps/powerpc/nptl/tls.h
@@ -108,19 +108,14 @@ typedef struct
/* This is the size of the initial TCB. */
# define TLS_INIT_TCB_SIZE 0
-/* Alignment requirements for the initial TCB. */
-# define TLS_INIT_TCB_ALIGN __alignof__ (struct pthread)
-
/* This is the size of the TCB. */
# define TLS_TCB_SIZE 0
-/* Alignment requirements for the TCB. */
-# define TLS_TCB_ALIGN __alignof__ (struct pthread)
-
/* This is the size we need before TCB. */
# define TLS_PRE_TCB_SIZE \
(sizeof (struct pthread) \
- + ((sizeof (tcbhead_t) + TLS_TCB_ALIGN - 1) & ~(TLS_TCB_ALIGN - 1)))
+ + ((sizeof (tcbhead_t) + __alignof (struct pthread) - 1) \
+ & ~(__alignof (struct pthread) - 1)))
/* The following assumes that TP (R2 or R13) points to the end of the
TCB + 0x7000 (per the ABI). This implies that TCB address is
diff --git a/sysdeps/riscv/nptl/tls.h b/sysdeps/riscv/nptl/tls.h
index bdc0a3a6f91b51e8..8c12d8f971adeddb 100644
--- a/sysdeps/riscv/nptl/tls.h
+++ b/sysdeps/riscv/nptl/tls.h
@@ -50,20 +50,15 @@ typedef struct
pointer, we don't need this. */
# define TLS_INIT_TCB_SIZE 0
-/* Alignment requirements for the initial TCB. */
-# define TLS_INIT_TCB_ALIGN __alignof__ (struct pthread)
-
/* This is the size of the TCB. Because our TCB is before the thread
pointer, we don't need this. */
# define TLS_TCB_SIZE 0
-/* Alignment requirements for the TCB. */
-# define TLS_TCB_ALIGN __alignof__ (struct pthread)
-
/* This is the size we need before TCB - actually, it includes the TCB. */
# define TLS_PRE_TCB_SIZE \
(sizeof (struct pthread) \
- + ((sizeof (tcbhead_t) + TLS_TCB_ALIGN - 1) & ~(TLS_TCB_ALIGN - 1)))
+ + ((sizeof (tcbhead_t) + __alignof (struct pthread) - 1) \
+ & ~(__alignof (struct pthread) - 1)))
/* The thread pointer tp points to the end of the TCB.
The pthread_descr structure is immediately in front of the TCB. */
diff --git a/sysdeps/s390/nptl/tls.h b/sysdeps/s390/nptl/tls.h
index 2cdd18eb2907c060..3b4c0ab32a9439a3 100644
--- a/sysdeps/s390/nptl/tls.h
+++ b/sysdeps/s390/nptl/tls.h
@@ -66,15 +66,9 @@ typedef struct
struct pthread even when not linked with -lpthread. */
# define TLS_INIT_TCB_SIZE sizeof (struct pthread)
-/* Alignment requirements for the initial TCB. */
-# define TLS_INIT_TCB_ALIGN __alignof__ (struct pthread)
-
/* This is the size of the TCB. */
# define TLS_TCB_SIZE sizeof (struct pthread)
-/* Alignment requirements for the TCB. */
-# define TLS_TCB_ALIGN __alignof__ (struct pthread)
-
/* The TCB can have any size and the memory following the address the
thread pointer points to is unspecified. Allocate the TCB there. */
# define TLS_TCB_AT_TP 1
diff --git a/sysdeps/sh/nptl/tls.h b/sysdeps/sh/nptl/tls.h
index 390640020e45f716..3e4d480b35951253 100644
--- a/sysdeps/sh/nptl/tls.h
+++ b/sysdeps/sh/nptl/tls.h
@@ -51,18 +51,12 @@ typedef struct
/* This is the size of the initial TCB. */
# define TLS_INIT_TCB_SIZE sizeof (tcbhead_t)
-/* Alignment requirements for the initial TCB. */
-# define TLS_INIT_TCB_ALIGN __alignof__ (tcbhead_t)
-
/* This is the size of the TCB. */
# define TLS_TCB_SIZE sizeof (tcbhead_t)
/* This is the size we need before TCB. */
# define TLS_PRE_TCB_SIZE sizeof (struct pthread)
-/* Alignment requirements for the TCB. */
-# define TLS_TCB_ALIGN __alignof__ (struct pthread)
-
/* The TLS blocks start right after the TCB. */
# define TLS_DTV_AT_TP 1
# define TLS_TCB_AT_TP 0
diff --git a/sysdeps/sparc/nptl/tls.h b/sysdeps/sparc/nptl/tls.h
index 376d729989e35660..3fb4ce6e6dacf28c 100644
--- a/sysdeps/sparc/nptl/tls.h
+++ b/sysdeps/sparc/nptl/tls.h
@@ -63,15 +63,9 @@ register struct pthread *__thread_self __asm__("%g7");
struct pthread even when not linked with -lpthread. */
# define TLS_INIT_TCB_SIZE sizeof (struct pthread)
-/* Alignment requirements for the initial TCB. */
-# define TLS_INIT_TCB_ALIGN __alignof__ (struct pthread)
-
/* This is the size of the TCB. */
# define TLS_TCB_SIZE sizeof (struct pthread)
-/* Alignment requirements for the TCB. */
-# define TLS_TCB_ALIGN __alignof__ (struct pthread)
-
/* The TCB can have any size and the memory following the address the
thread pointer points to is unspecified. Allocate the TCB there. */
# define TLS_TCB_AT_TP 1
diff --git a/sysdeps/x86_64/nptl/tls.h b/sysdeps/x86_64/nptl/tls.h
index 3af1836e28b26fdb..50f7e8b544f9e6fc 100644
--- a/sysdeps/x86_64/nptl/tls.h
+++ b/sysdeps/x86_64/nptl/tls.h
@@ -106,15 +106,9 @@ _Static_assert (offsetof (tcbhead_t, __glibc_unused2) == 0x80,
struct pthread even when not linked with -lpthread. */
# define TLS_INIT_TCB_SIZE sizeof (struct pthread)
-/* Alignment requirements for the initial TCB. */
-# define TLS_INIT_TCB_ALIGN __alignof__ (struct pthread)
-
/* This is the size of the TCB. */
# define TLS_TCB_SIZE sizeof (struct pthread)
-/* Alignment requirements for the TCB. */
-# define TLS_TCB_ALIGN __alignof__ (struct pthread)
-
/* The TCB can have any size and the memory following the address the
thread pointer points to is unspecified. Allocate the TCB there. */
# define TLS_TCB_AT_TP 1