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[v8,1/3] String: Add support for __memcmpeq() ABI on all targets

Message ID 20211021223850.415607-1-goldstein.w.n@gmail.com
State Superseded
Headers show
Series [v8,1/3] String: Add support for __memcmpeq() ABI on all targets | expand

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Context Check Description
dj/TryBot-apply_patch success Patch applied to master at the time it was sent

Commit Message

Noah Goldstein Oct. 21, 2021, 10:38 p.m. UTC
No bug.

This commit adds support for __memcmpeq() as a new ABI for all
targets. In this commit __memcmpeq() is implemented only as an alias
to the corresponding targets memcmp() implementation. __memcmpeq() is
added as a new symbol starting with GLIBC_2.35 and defined in string.h
with comments explaining its behavior. Basic tests that it is callable
and works where added in string/tester.c

As discussed in the proposal "Add new ABI '__memcmpeq()' to libc"
__memcmpeq() is essentially a reserved namespace for bcmp(). The means
is shares the same specifications as memcmp() except the return value
for non-equal byte sequences is any non-zero value. This is less
strict than memcmp()'s return value specification and can be better
optimized when a boolean return is all that is needed.

__memcmpeq() is meant to only be called by compilers if they can prove
that the return value of a memcmp() call is only used for its boolean
value.

All tests in string/tester.c passed. As well build succeeds on
x86_64-linux-gnu target.
---
 string/Versions                                  |  3 +++
 string/memcmp.c                                  |  2 ++
 string/string.h                                  | 16 ++++++++++++++++
 string/tester.c                                  | 16 ++++++++++++++++
 sysdeps/aarch64/memcmp.S                         |  2 ++
 sysdeps/csky/abiv2/memcmp.S                      |  1 +
 sysdeps/i386/i686/memcmp.S                       |  2 ++
 sysdeps/i386/i686/multiarch/memcmp.c             |  1 +
 sysdeps/i386/memcmp.S                            |  2 ++
 sysdeps/ia64/memcmp.S                            |  1 +
 sysdeps/mach/hurd/i386/libc.abilist              |  1 +
 sysdeps/powerpc/powerpc32/405/memcmp.S           |  1 +
 sysdeps/powerpc/powerpc32/power4/memcmp.S        |  1 +
 sysdeps/powerpc/powerpc32/power7/memcmp.S        |  1 +
 sysdeps/powerpc/powerpc64/le/power10/memcmp.S    |  1 +
 sysdeps/powerpc/powerpc64/power4/memcmp.S        |  1 +
 sysdeps/powerpc/powerpc64/power7/memcmp.S        |  1 +
 sysdeps/powerpc/powerpc64/power8/memcmp.S        |  1 +
 sysdeps/s390/memcmp-z900.S                       |  1 +
 sysdeps/s390/memcmp.c                            |  1 +
 sysdeps/sparc/sparc64/memcmp.S                   |  2 ++
 sysdeps/unix/sysv/linux/aarch64/libc.abilist     |  1 +
 sysdeps/unix/sysv/linux/alpha/libc.abilist       |  1 +
 sysdeps/unix/sysv/linux/arc/libc.abilist         |  1 +
 sysdeps/unix/sysv/linux/arm/be/libc.abilist      |  1 +
 sysdeps/unix/sysv/linux/arm/le/libc.abilist      |  1 +
 sysdeps/unix/sysv/linux/csky/libc.abilist        |  1 +
 sysdeps/unix/sysv/linux/hppa/libc.abilist        |  1 +
 sysdeps/unix/sysv/linux/i386/libc.abilist        |  1 +
 sysdeps/unix/sysv/linux/ia64/libc.abilist        |  1 +
 .../unix/sysv/linux/m68k/coldfire/libc.abilist   |  1 +
 sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist |  1 +
 .../unix/sysv/linux/microblaze/be/libc.abilist   |  1 +
 .../unix/sysv/linux/microblaze/le/libc.abilist   |  1 +
 .../unix/sysv/linux/mips/mips32/fpu/libc.abilist |  1 +
 .../sysv/linux/mips/mips32/nofpu/libc.abilist    |  1 +
 .../unix/sysv/linux/mips/mips64/n32/libc.abilist |  1 +
 .../unix/sysv/linux/mips/mips64/n64/libc.abilist |  1 +
 sysdeps/unix/sysv/linux/nios2/libc.abilist       |  1 +
 .../linux/powerpc/powerpc32/fpu/libc.abilist     |  1 +
 .../linux/powerpc/powerpc32/nofpu/libc.abilist   |  1 +
 .../sysv/linux/powerpc/powerpc64/be/libc.abilist |  1 +
 .../sysv/linux/powerpc/powerpc64/le/libc.abilist |  1 +
 sysdeps/unix/sysv/linux/riscv/rv32/libc.abilist  |  1 +
 sysdeps/unix/sysv/linux/riscv/rv64/libc.abilist  |  1 +
 .../unix/sysv/linux/s390/s390-32/libc.abilist    |  1 +
 .../unix/sysv/linux/s390/s390-64/libc.abilist    |  1 +
 sysdeps/unix/sysv/linux/sh/be/libc.abilist       |  1 +
 sysdeps/unix/sysv/linux/sh/le/libc.abilist       |  1 +
 .../unix/sysv/linux/sparc/sparc32/libc.abilist   |  1 +
 .../unix/sysv/linux/sparc/sparc64/libc.abilist   |  1 +
 sysdeps/unix/sysv/linux/x86_64/64/libc.abilist   |  1 +
 sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist  |  1 +
 sysdeps/x86_64/memcmp.S                          |  2 ++
 sysdeps/x86_64/multiarch/memcmp.c                |  2 ++
 55 files changed, 94 insertions(+)

Comments

H.J. Lu Oct. 21, 2021, 10:50 p.m. UTC | #1
On Thu, Oct 21, 2021 at 3:38 PM Noah Goldstein <goldstein.w.n@gmail.com> wrote:
>
> No bug.
>
> This commit adds support for __memcmpeq() as a new ABI for all
> targets. In this commit __memcmpeq() is implemented only as an alias
> to the corresponding targets memcmp() implementation. __memcmpeq() is
> added as a new symbol starting with GLIBC_2.35 and defined in string.h
> with comments explaining its behavior. Basic tests that it is callable
> and works where added in string/tester.c
>
> As discussed in the proposal "Add new ABI '__memcmpeq()' to libc"
> __memcmpeq() is essentially a reserved namespace for bcmp(). The means
> is shares the same specifications as memcmp() except the return value
> for non-equal byte sequences is any non-zero value. This is less
> strict than memcmp()'s return value specification and can be better
> optimized when a boolean return is all that is needed.
>
> __memcmpeq() is meant to only be called by compilers if they can prove
> that the return value of a memcmp() call is only used for its boolean
> value.
>
> All tests in string/tester.c passed. As well build succeeds on
> x86_64-linux-gnu target.
> ---
>  string/Versions                                  |  3 +++
>  string/memcmp.c                                  |  2 ++
>  string/string.h                                  | 16 ++++++++++++++++
>  string/tester.c                                  | 16 ++++++++++++++++
>  sysdeps/aarch64/memcmp.S                         |  2 ++
>  sysdeps/csky/abiv2/memcmp.S                      |  1 +
>  sysdeps/i386/i686/memcmp.S                       |  2 ++
>  sysdeps/i386/i686/multiarch/memcmp.c             |  1 +
>  sysdeps/i386/memcmp.S                            |  2 ++
>  sysdeps/ia64/memcmp.S                            |  1 +
>  sysdeps/mach/hurd/i386/libc.abilist              |  1 +
>  sysdeps/powerpc/powerpc32/405/memcmp.S           |  1 +
>  sysdeps/powerpc/powerpc32/power4/memcmp.S        |  1 +
>  sysdeps/powerpc/powerpc32/power7/memcmp.S        |  1 +
>  sysdeps/powerpc/powerpc64/le/power10/memcmp.S    |  1 +
>  sysdeps/powerpc/powerpc64/power4/memcmp.S        |  1 +
>  sysdeps/powerpc/powerpc64/power7/memcmp.S        |  1 +
>  sysdeps/powerpc/powerpc64/power8/memcmp.S        |  1 +
>  sysdeps/s390/memcmp-z900.S                       |  1 +
>  sysdeps/s390/memcmp.c                            |  1 +
>  sysdeps/sparc/sparc64/memcmp.S                   |  2 ++
>  sysdeps/unix/sysv/linux/aarch64/libc.abilist     |  1 +
>  sysdeps/unix/sysv/linux/alpha/libc.abilist       |  1 +
>  sysdeps/unix/sysv/linux/arc/libc.abilist         |  1 +
>  sysdeps/unix/sysv/linux/arm/be/libc.abilist      |  1 +
>  sysdeps/unix/sysv/linux/arm/le/libc.abilist      |  1 +
>  sysdeps/unix/sysv/linux/csky/libc.abilist        |  1 +
>  sysdeps/unix/sysv/linux/hppa/libc.abilist        |  1 +
>  sysdeps/unix/sysv/linux/i386/libc.abilist        |  1 +
>  sysdeps/unix/sysv/linux/ia64/libc.abilist        |  1 +
>  .../unix/sysv/linux/m68k/coldfire/libc.abilist   |  1 +
>  sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist |  1 +
>  .../unix/sysv/linux/microblaze/be/libc.abilist   |  1 +
>  .../unix/sysv/linux/microblaze/le/libc.abilist   |  1 +
>  .../unix/sysv/linux/mips/mips32/fpu/libc.abilist |  1 +
>  .../sysv/linux/mips/mips32/nofpu/libc.abilist    |  1 +
>  .../unix/sysv/linux/mips/mips64/n32/libc.abilist |  1 +
>  .../unix/sysv/linux/mips/mips64/n64/libc.abilist |  1 +
>  sysdeps/unix/sysv/linux/nios2/libc.abilist       |  1 +
>  .../linux/powerpc/powerpc32/fpu/libc.abilist     |  1 +
>  .../linux/powerpc/powerpc32/nofpu/libc.abilist   |  1 +
>  .../sysv/linux/powerpc/powerpc64/be/libc.abilist |  1 +
>  .../sysv/linux/powerpc/powerpc64/le/libc.abilist |  1 +
>  sysdeps/unix/sysv/linux/riscv/rv32/libc.abilist  |  1 +
>  sysdeps/unix/sysv/linux/riscv/rv64/libc.abilist  |  1 +
>  .../unix/sysv/linux/s390/s390-32/libc.abilist    |  1 +
>  .../unix/sysv/linux/s390/s390-64/libc.abilist    |  1 +
>  sysdeps/unix/sysv/linux/sh/be/libc.abilist       |  1 +
>  sysdeps/unix/sysv/linux/sh/le/libc.abilist       |  1 +
>  .../unix/sysv/linux/sparc/sparc32/libc.abilist   |  1 +
>  .../unix/sysv/linux/sparc/sparc64/libc.abilist   |  1 +
>  sysdeps/unix/sysv/linux/x86_64/64/libc.abilist   |  1 +
>  sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist  |  1 +
>  sysdeps/x86_64/memcmp.S                          |  2 ++
>  sysdeps/x86_64/multiarch/memcmp.c                |  2 ++
>  55 files changed, 94 insertions(+)
>
> diff --git a/string/Versions b/string/Versions
> index 298ecd401a..864c4cf7a4 100644
> --- a/string/Versions
> +++ b/string/Versions
> @@ -89,4 +89,7 @@ libc {
>      sigdescr_np; sigabbrev_np;
>      strerrordesc_np; strerrorname_np;
>    }
> +  GLIBC_2.35 {
> +    __memcmpeq;
> +  }
>  }
> diff --git a/string/memcmp.c b/string/memcmp.c
> index 9b46d7a905..5020be00e0 100644
> --- a/string/memcmp.c
> +++ b/string/memcmp.c
> @@ -358,4 +358,6 @@ libc_hidden_builtin_def(memcmp)
>  #ifdef weak_alias
>  # undef bcmp
>  weak_alias (memcmp, bcmp)
> +# undef __memcmpeq
> +weak_alias (memcmp, __memcmpeq)
>  #endif
> diff --git a/string/string.h b/string/string.h
> index b1b083edce..e70feeaeea 100644
> --- a/string/string.h
> +++ b/string/string.h
> @@ -64,6 +64,22 @@ extern void *memset (void *__s, int __c, size_t __n) __THROW __nonnull ((1));
>  extern int memcmp (const void *__s1, const void *__s2, size_t __n)
>       __THROW __attribute_pure__ __nonnull ((1, 2));
>
> +/* Compare N bytes of S1 and S2.  Return zero if S1 and S2 are equal.
> +   Return some non-zero value otherwise.
> +
> +   Essentially __memcmpeq has the exact same semantics as memcmp
> +   except the return value is less constrained.  memcmp is always a
> +   correct implementation of __memcmpeq.  As well !!memcmp, -memcmp,
> +   or bcmp are correct implementations.
> +
> +   __memcmpeq is meant to be used by compilers when memcmp return is
> +   only used for its bolean value.
> +
> +   __memcmpeq is declared only for use by compilers.  Programs should
> +   continue to use memcmp.  */
> +extern int __memcmpeq (const void *__s1, const void *__s2, size_t __n)
> +     __THROW __attribute_pure__ __nonnull ((1, 2));
> +
>  /* Search N bytes of S for C.  */
>  #ifdef __CORRECT_ISO_CPP_STRING_H_PROTO
>  extern "C++"
> diff --git a/string/tester.c b/string/tester.c
> index 778160ae6e..605b3f00f9 100644
> --- a/string/tester.c
> +++ b/string/tester.c
> @@ -1449,6 +1449,19 @@ test_bcmp (void)
>    check(bcmp("abc", "def", 0) == 0, 8);        /* Zero count. */
>  }
>
> +static void
> +test_memcmpeq (void)
> +{
> +  it = "__memcmpeq";
> +  check (__memcmpeq ("a", "a", 1) == 0, 1); /* Identity.  */
> +  check (__memcmpeq ("abc", "abc", 3) == 0, 2); /* Multicharacter.  */
> +  check (__memcmpeq ("abcd", "abce", 4) != 0, 3); /* Honestly unequal.  */
> +  check (__memcmpeq ("abce", "abcd", 4) != 0, 4);
> +  check (__memcmpeq ("alph", "beta", 4) != 0, 5);
> +  check (__memcmpeq ("abce", "abcd", 3) == 0, 6); /* Count limited.  */
> +  check (__memcmpeq ("abc", "def", 0) == 0, 8); /* Zero count.  */
> +}
> +
>  static void
>  test_strerror (void)
>  {
> @@ -1611,6 +1624,9 @@ main (void)
>    /* bcmp - somewhat like memcmp.  */
>    test_bcmp ();
>
> +  /* __memcmpeq - somewhat like memcmp.  */
> +  test_memcmpeq ();
> +
>    /* strndup.  */
>    test_strndup ();
>
> diff --git a/sysdeps/aarch64/memcmp.S b/sysdeps/aarch64/memcmp.S
> index c1937f6f5c..bc932eff2a 100644
> --- a/sysdeps/aarch64/memcmp.S
> +++ b/sysdeps/aarch64/memcmp.S
> @@ -177,4 +177,6 @@ L(ret_0):
>  END (memcmp)
>  #undef bcmp
>  weak_alias (memcmp, bcmp)
> +#undef __memcmpeq
> +weak_alias (memcmp, __memcmpeq)

Can we use strong_alias for __memcmpeq?

>  libc_hidden_builtin_def (memcmp)
> diff --git a/sysdeps/csky/abiv2/memcmp.S b/sysdeps/csky/abiv2/memcmp.S
> index 1560387618..d61fca0f29 100644
> --- a/sysdeps/csky/abiv2/memcmp.S
> +++ b/sysdeps/csky/abiv2/memcmp.S
> @@ -138,5 +138,6 @@ ENTRY (memcmp)
>         br      .L_s1_aligned
>  END (memcmp)
>  weak_alias (memcmp, bcmp)
> +weak_alias (memcmp, __memcmpeq)
>  libc_hidden_def (memcmp)
>  .weak memcmp
> diff --git a/sysdeps/i386/i686/memcmp.S b/sysdeps/i386/i686/memcmp.S
> index b26b124fad..0194f8deab 100644
> --- a/sysdeps/i386/i686/memcmp.S
> +++ b/sysdeps/i386/i686/memcmp.S
> @@ -405,4 +405,6 @@ L(table_32bytes) :
>
>  #undef bcmp
>  weak_alias (memcmp, bcmp)
> +#undef __memcmpeq
> +weak_alias (memcmp, __memcmpeq)
>  libc_hidden_builtin_def (memcmp)
> diff --git a/sysdeps/i386/i686/multiarch/memcmp.c b/sysdeps/i386/i686/multiarch/memcmp.c
> index 6e058a8857..956fc8e601 100644
> --- a/sysdeps/i386/i686/multiarch/memcmp.c
> +++ b/sysdeps/i386/i686/multiarch/memcmp.c
> @@ -29,4 +29,5 @@
>  libc_ifunc_redirected (__redirect_memcmp, memcmp, IFUNC_SELECTOR ());
>
>  weak_alias (memcmp, bcmp)
> +weak_alias (memcmp, __memcmpeq)
>  #endif
> diff --git a/sysdeps/i386/memcmp.S b/sysdeps/i386/memcmp.S
> index 1f212b0f6d..18e225f963 100644
> --- a/sysdeps/i386/memcmp.S
> +++ b/sysdeps/i386/memcmp.S
> @@ -70,4 +70,6 @@ END (memcmp)
>
>  #undef bcmp
>  weak_alias (memcmp, bcmp)
> +#undef __memcmpeq
> +weak_alias (memcmp, __memcmpeq)
>  libc_hidden_builtin_def (memcmp)
> diff --git a/sysdeps/ia64/memcmp.S b/sysdeps/ia64/memcmp.S
> index 97539c23fd..4488e0eba4 100644
> --- a/sysdeps/ia64/memcmp.S
> +++ b/sysdeps/ia64/memcmp.S
> @@ -160,4 +160,5 @@ ENTRY(memcmp)
>  END(memcmp)
>
>  weak_alias (memcmp, bcmp)
> +weak_alias (memcmp, __memcmpeq)
>  libc_hidden_builtin_def (memcmp)
> diff --git a/sysdeps/mach/hurd/i386/libc.abilist b/sysdeps/mach/hurd/i386/libc.abilist
> index c5da10a0cd..e849d6fa35 100644
> --- a/sysdeps/mach/hurd/i386/libc.abilist
> +++ b/sysdeps/mach/hurd/i386/libc.abilist
> @@ -2285,6 +2285,7 @@ GLIBC_2.34 res_send F
>  GLIBC_2.34 shm_open F
>  GLIBC_2.34 shm_unlink F
>  GLIBC_2.34 timespec_getres F
> +GLIBC_2.35 __memcmpeq F
>  GLIBC_2.4 __confstr_chk F
>  GLIBC_2.4 __fgets_chk F
>  GLIBC_2.4 __fgets_unlocked_chk F
> diff --git a/sysdeps/powerpc/powerpc32/405/memcmp.S b/sysdeps/powerpc/powerpc32/405/memcmp.S
> index 6a6a54d90f..e8b1b6c9bd 100644
> --- a/sysdeps/powerpc/powerpc32/405/memcmp.S
> +++ b/sysdeps/powerpc/powerpc32/405/memcmp.S
> @@ -126,3 +126,4 @@ L(st2):
>  END (memcmp)
>  libc_hidden_builtin_def (memcmp)
>  weak_alias (memcmp,bcmp)
> +weak_alias (memcmp, __memcmpeq)
> diff --git a/sysdeps/powerpc/powerpc32/power4/memcmp.S b/sysdeps/powerpc/powerpc32/power4/memcmp.S
> index 814d2f211d..e4dde875bb 100644
> --- a/sysdeps/powerpc/powerpc32/power4/memcmp.S
> +++ b/sysdeps/powerpc/powerpc32/power4/memcmp.S
> @@ -1373,3 +1373,4 @@ END (memcmp)
>
>  libc_hidden_builtin_def (memcmp)
>  weak_alias (memcmp, bcmp)
> +weak_alias (memcmp, __memcmpeq)
> diff --git a/sysdeps/powerpc/powerpc32/power7/memcmp.S b/sysdeps/powerpc/powerpc32/power7/memcmp.S
> index 8a19953e2d..e60a62fc86 100644
> --- a/sysdeps/powerpc/powerpc32/power7/memcmp.S
> +++ b/sysdeps/powerpc/powerpc32/power7/memcmp.S
> @@ -1373,3 +1373,4 @@ END (memcmp)
>
>  libc_hidden_builtin_def (memcmp)
>  weak_alias (memcmp, bcmp)
> +weak_alias (memcmp, __memcmpeq)
> diff --git a/sysdeps/powerpc/powerpc64/le/power10/memcmp.S b/sysdeps/powerpc/powerpc64/le/power10/memcmp.S
> index 52f244e7e7..c7fe8047ca 100644
> --- a/sysdeps/powerpc/powerpc64/le/power10/memcmp.S
> +++ b/sysdeps/powerpc/powerpc64/le/power10/memcmp.S
> @@ -177,3 +177,4 @@ L(tail8):
>  END (MEMCMP)
>  libc_hidden_builtin_def (memcmp)
>  weak_alias (memcmp, bcmp)
> +weak_alias (memcmp, __memcmpeq)
> diff --git a/sysdeps/powerpc/powerpc64/power4/memcmp.S b/sysdeps/powerpc/powerpc64/power4/memcmp.S
> index dc1be3a0d8..4ab4a90496 100644
> --- a/sysdeps/powerpc/powerpc64/power4/memcmp.S
> +++ b/sysdeps/powerpc/powerpc64/power4/memcmp.S
> @@ -1374,3 +1374,4 @@ L(duzeroLength):
>  END (MEMCMP)
>  libc_hidden_builtin_def (memcmp)
>  weak_alias (memcmp, bcmp)
> +weak_alias (memcmp, __memcmpeq)
> diff --git a/sysdeps/powerpc/powerpc64/power7/memcmp.S b/sysdeps/powerpc/powerpc64/power7/memcmp.S
> index bc034a55bc..b541978b5f 100644
> --- a/sysdeps/powerpc/powerpc64/power7/memcmp.S
> +++ b/sysdeps/powerpc/powerpc64/power7/memcmp.S
> @@ -1059,3 +1059,4 @@ L(duzeroLength):
>  END (MEMCMP)
>  libc_hidden_builtin_def (memcmp)
>  weak_alias (memcmp, bcmp)
> +weak_alias (memcmp, __memcmpeq)
> diff --git a/sysdeps/powerpc/powerpc64/power8/memcmp.S b/sysdeps/powerpc/powerpc64/power8/memcmp.S
> index b676b09a9b..d4f84a5b6f 100644
> --- a/sysdeps/powerpc/powerpc64/power8/memcmp.S
> +++ b/sysdeps/powerpc/powerpc64/power8/memcmp.S
> @@ -1442,3 +1442,4 @@ L(duzeroLength):
>  END (MEMCMP)
>  libc_hidden_builtin_def (memcmp)
>  weak_alias (memcmp, bcmp)
> +weak_alias (memcmp, __memcmpeq)
> diff --git a/sysdeps/s390/memcmp-z900.S b/sysdeps/s390/memcmp-z900.S
> index 995d52e47d..0942d32814 100644
> --- a/sysdeps/s390/memcmp-z900.S
> +++ b/sysdeps/s390/memcmp-z900.S
> @@ -164,6 +164,7 @@ END(MEMCMP_Z196)
>     Otherwise see sysdeps/s390/memcmp.c.  */
>  strong_alias (MEMCMP_DEFAULT, memcmp)
>  weak_alias (memcmp, bcmp)
> +weak_alias (memcmp, __memcmpeq)
>  #endif
>
>  #if defined SHARED && IS_IN (libc)
> diff --git a/sysdeps/s390/memcmp.c b/sysdeps/s390/memcmp.c
> index 0b4e9da717..475fc45d3a 100644
> --- a/sysdeps/s390/memcmp.c
> +++ b/sysdeps/s390/memcmp.c
> @@ -46,4 +46,5 @@ s390_libc_ifunc_expr (__redirect_memcmp, memcmp,
>                       })
>                       )
>  weak_alias (memcmp, bcmp);
> +weak_alias (memcmp, __memcmpeq)
>  #endif
> diff --git a/sysdeps/sparc/sparc64/memcmp.S b/sysdeps/sparc/sparc64/memcmp.S
> index d8d9ff9b24..edcc19915a 100644
> --- a/sysdeps/sparc/sparc64/memcmp.S
> +++ b/sysdeps/sparc/sparc64/memcmp.S
> @@ -137,4 +137,6 @@ END(memcmp)
>
>  #undef bcmp
>  weak_alias (memcmp, bcmp)
> +#undef __memcmpeq
> +weak_alias (memcmp, __memcmpeq)
>  libc_hidden_builtin_def (memcmp)
> diff --git a/sysdeps/unix/sysv/linux/aarch64/libc.abilist b/sysdeps/unix/sysv/linux/aarch64/libc.abilist
> index 21a2e50a88..f227ae6cee 100644
> --- a/sysdeps/unix/sysv/linux/aarch64/libc.abilist
> +++ b/sysdeps/unix/sysv/linux/aarch64/libc.abilist
> @@ -2612,3 +2612,4 @@ GLIBC_2.34 tss_create F
>  GLIBC_2.34 tss_delete F
>  GLIBC_2.34 tss_get F
>  GLIBC_2.34 tss_set F
> +GLIBC_2.35 __memcmpeq F
> diff --git a/sysdeps/unix/sysv/linux/alpha/libc.abilist b/sysdeps/unix/sysv/linux/alpha/libc.abilist
> index a201fd69ba..0ccc3fc73e 100644
> --- a/sysdeps/unix/sysv/linux/alpha/libc.abilist
> +++ b/sysdeps/unix/sysv/linux/alpha/libc.abilist
> @@ -2709,6 +2709,7 @@ GLIBC_2.34 tss_create F
>  GLIBC_2.34 tss_delete F
>  GLIBC_2.34 tss_get F
>  GLIBC_2.34 tss_set F
> +GLIBC_2.35 __memcmpeq F
>  GLIBC_2.4 _IO_fprintf F
>  GLIBC_2.4 _IO_printf F
>  GLIBC_2.4 _IO_sprintf F
> diff --git a/sysdeps/unix/sysv/linux/arc/libc.abilist b/sysdeps/unix/sysv/linux/arc/libc.abilist
> index 2611436937..fd80704787 100644
> --- a/sysdeps/unix/sysv/linux/arc/libc.abilist
> +++ b/sysdeps/unix/sysv/linux/arc/libc.abilist
> @@ -2373,3 +2373,4 @@ GLIBC_2.34 tss_create F
>  GLIBC_2.34 tss_delete F
>  GLIBC_2.34 tss_get F
>  GLIBC_2.34 tss_set F
> +GLIBC_2.35 __memcmpeq F
> diff --git a/sysdeps/unix/sysv/linux/arm/be/libc.abilist b/sysdeps/unix/sysv/linux/arm/be/libc.abilist
> index a426241965..2ae6c58b8a 100644
> --- a/sysdeps/unix/sysv/linux/arm/be/libc.abilist
> +++ b/sysdeps/unix/sysv/linux/arm/be/libc.abilist
> @@ -491,6 +491,7 @@ GLIBC_2.34 tss_create F
>  GLIBC_2.34 tss_delete F
>  GLIBC_2.34 tss_get F
>  GLIBC_2.34 tss_set F
> +GLIBC_2.35 __memcmpeq F
>  GLIBC_2.4 _Exit F
>  GLIBC_2.4 _IO_2_1_stderr_ D 0xa0
>  GLIBC_2.4 _IO_2_1_stdin_ D 0xa0
> diff --git a/sysdeps/unix/sysv/linux/arm/le/libc.abilist b/sysdeps/unix/sysv/linux/arm/le/libc.abilist
> index 02f80418cc..fcfd1e8594 100644
> --- a/sysdeps/unix/sysv/linux/arm/le/libc.abilist
> +++ b/sysdeps/unix/sysv/linux/arm/le/libc.abilist
> @@ -488,6 +488,7 @@ GLIBC_2.34 tss_create F
>  GLIBC_2.34 tss_delete F
>  GLIBC_2.34 tss_get F
>  GLIBC_2.34 tss_set F
> +GLIBC_2.35 __memcmpeq F
>  GLIBC_2.4 _Exit F
>  GLIBC_2.4 _IO_2_1_stderr_ D 0xa0
>  GLIBC_2.4 _IO_2_1_stdin_ D 0xa0
> diff --git a/sysdeps/unix/sysv/linux/csky/libc.abilist b/sysdeps/unix/sysv/linux/csky/libc.abilist
> index b7676eb372..ba034b8541 100644
> --- a/sysdeps/unix/sysv/linux/csky/libc.abilist
> +++ b/sysdeps/unix/sysv/linux/csky/libc.abilist
> @@ -2647,3 +2647,4 @@ GLIBC_2.34 tss_create F
>  GLIBC_2.34 tss_delete F
>  GLIBC_2.34 tss_get F
>  GLIBC_2.34 tss_set F
> +GLIBC_2.35 __memcmpeq F
> diff --git a/sysdeps/unix/sysv/linux/hppa/libc.abilist b/sysdeps/unix/sysv/linux/hppa/libc.abilist
> index f6965c9d95..b7460bec8a 100644
> --- a/sysdeps/unix/sysv/linux/hppa/libc.abilist
> +++ b/sysdeps/unix/sysv/linux/hppa/libc.abilist
> @@ -2596,6 +2596,7 @@ GLIBC_2.34 tss_create F
>  GLIBC_2.34 tss_delete F
>  GLIBC_2.34 tss_get F
>  GLIBC_2.34 tss_set F
> +GLIBC_2.35 __memcmpeq F
>  GLIBC_2.4 __confstr_chk F
>  GLIBC_2.4 __fgets_chk F
>  GLIBC_2.4 __fgets_unlocked_chk F
> diff --git a/sysdeps/unix/sysv/linux/i386/libc.abilist b/sysdeps/unix/sysv/linux/i386/libc.abilist
> index 2e7603d9ed..a4dc341ded 100644
> --- a/sysdeps/unix/sysv/linux/i386/libc.abilist
> +++ b/sysdeps/unix/sysv/linux/i386/libc.abilist
> @@ -2780,6 +2780,7 @@ GLIBC_2.34 tss_create F
>  GLIBC_2.34 tss_delete F
>  GLIBC_2.34 tss_get F
>  GLIBC_2.34 tss_set F
> +GLIBC_2.35 __memcmpeq F
>  GLIBC_2.4 __confstr_chk F
>  GLIBC_2.4 __fgets_chk F
>  GLIBC_2.4 __fgets_unlocked_chk F
> diff --git a/sysdeps/unix/sysv/linux/ia64/libc.abilist b/sysdeps/unix/sysv/linux/ia64/libc.abilist
> index dd3a56d3fe..94b222dbc7 100644
> --- a/sysdeps/unix/sysv/linux/ia64/libc.abilist
> +++ b/sysdeps/unix/sysv/linux/ia64/libc.abilist
> @@ -2547,6 +2547,7 @@ GLIBC_2.34 tss_create F
>  GLIBC_2.34 tss_delete F
>  GLIBC_2.34 tss_get F
>  GLIBC_2.34 tss_set F
> +GLIBC_2.35 __memcmpeq F
>  GLIBC_2.4 __confstr_chk F
>  GLIBC_2.4 __fgets_chk F
>  GLIBC_2.4 __fgets_unlocked_chk F
> diff --git a/sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist b/sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist
> index c1e0ea9c10..12fd3b6310 100644
> --- a/sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist
> +++ b/sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist
> @@ -492,6 +492,7 @@ GLIBC_2.34 tss_create F
>  GLIBC_2.34 tss_delete F
>  GLIBC_2.34 tss_get F
>  GLIBC_2.34 tss_set F
> +GLIBC_2.35 __memcmpeq F
>  GLIBC_2.4 _Exit F
>  GLIBC_2.4 _IO_2_1_stderr_ D 0x98
>  GLIBC_2.4 _IO_2_1_stdin_ D 0x98
> diff --git a/sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist b/sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist
> index 93161048ca..4d2296007a 100644
> --- a/sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist
> +++ b/sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist
> @@ -2723,6 +2723,7 @@ GLIBC_2.34 tss_create F
>  GLIBC_2.34 tss_delete F
>  GLIBC_2.34 tss_get F
>  GLIBC_2.34 tss_set F
> +GLIBC_2.35 __memcmpeq F
>  GLIBC_2.4 __confstr_chk F
>  GLIBC_2.4 __fgets_chk F
>  GLIBC_2.4 __fgets_unlocked_chk F
> diff --git a/sysdeps/unix/sysv/linux/microblaze/be/libc.abilist b/sysdeps/unix/sysv/linux/microblaze/be/libc.abilist
> index 0aaeec8a27..a223278a3d 100644
> --- a/sysdeps/unix/sysv/linux/microblaze/be/libc.abilist
> +++ b/sysdeps/unix/sysv/linux/microblaze/be/libc.abilist
> @@ -2696,3 +2696,4 @@ GLIBC_2.34 tss_create F
>  GLIBC_2.34 tss_delete F
>  GLIBC_2.34 tss_get F
>  GLIBC_2.34 tss_set F
> +GLIBC_2.35 __memcmpeq F
> diff --git a/sysdeps/unix/sysv/linux/microblaze/le/libc.abilist b/sysdeps/unix/sysv/linux/microblaze/le/libc.abilist
> index bec5f456c9..780a4f5b0b 100644
> --- a/sysdeps/unix/sysv/linux/microblaze/le/libc.abilist
> +++ b/sysdeps/unix/sysv/linux/microblaze/le/libc.abilist
> @@ -2693,3 +2693,4 @@ GLIBC_2.34 tss_create F
>  GLIBC_2.34 tss_delete F
>  GLIBC_2.34 tss_get F
>  GLIBC_2.34 tss_set F
> +GLIBC_2.35 __memcmpeq F
> diff --git a/sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist b/sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist
> index 97d2127f78..cd65136062 100644
> --- a/sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist
> +++ b/sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist
> @@ -2688,6 +2688,7 @@ GLIBC_2.34 tss_create F
>  GLIBC_2.34 tss_delete F
>  GLIBC_2.34 tss_get F
>  GLIBC_2.34 tss_set F
> +GLIBC_2.35 __memcmpeq F
>  GLIBC_2.4 __confstr_chk F
>  GLIBC_2.4 __fgets_chk F
>  GLIBC_2.4 __fgets_unlocked_chk F
> diff --git a/sysdeps/unix/sysv/linux/mips/mips32/nofpu/libc.abilist b/sysdeps/unix/sysv/linux/mips/mips32/nofpu/libc.abilist
> index acb0756c11..b5b9902db5 100644
> --- a/sysdeps/unix/sysv/linux/mips/mips32/nofpu/libc.abilist
> +++ b/sysdeps/unix/sysv/linux/mips/mips32/nofpu/libc.abilist
> @@ -2686,6 +2686,7 @@ GLIBC_2.34 tss_create F
>  GLIBC_2.34 tss_delete F
>  GLIBC_2.34 tss_get F
>  GLIBC_2.34 tss_set F
> +GLIBC_2.35 __memcmpeq F
>  GLIBC_2.4 __confstr_chk F
>  GLIBC_2.4 __fgets_chk F
>  GLIBC_2.4 __fgets_unlocked_chk F
> diff --git a/sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist b/sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist
> index ebc21dde1e..57593d5f94 100644
> --- a/sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist
> +++ b/sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist
> @@ -2694,6 +2694,7 @@ GLIBC_2.34 tss_create F
>  GLIBC_2.34 tss_delete F
>  GLIBC_2.34 tss_get F
>  GLIBC_2.34 tss_set F
> +GLIBC_2.35 __memcmpeq F
>  GLIBC_2.4 __confstr_chk F
>  GLIBC_2.4 __fgets_chk F
>  GLIBC_2.4 __fgets_unlocked_chk F
> diff --git a/sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist b/sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist
> index c68f7e3c6c..e944d76bed 100644
> --- a/sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist
> +++ b/sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist
> @@ -2598,6 +2598,7 @@ GLIBC_2.34 tss_create F
>  GLIBC_2.34 tss_delete F
>  GLIBC_2.34 tss_get F
>  GLIBC_2.34 tss_set F
> +GLIBC_2.35 __memcmpeq F
>  GLIBC_2.4 __confstr_chk F
>  GLIBC_2.4 __fgets_chk F
>  GLIBC_2.4 __fgets_unlocked_chk F
> diff --git a/sysdeps/unix/sysv/linux/nios2/libc.abilist b/sysdeps/unix/sysv/linux/nios2/libc.abilist
> index e5b6834f14..8af5a3a90d 100644
> --- a/sysdeps/unix/sysv/linux/nios2/libc.abilist
> +++ b/sysdeps/unix/sysv/linux/nios2/libc.abilist
> @@ -2735,3 +2735,4 @@ GLIBC_2.34 tss_create F
>  GLIBC_2.34 tss_delete F
>  GLIBC_2.34 tss_get F
>  GLIBC_2.34 tss_set F
> +GLIBC_2.35 __memcmpeq F
> diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist b/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist
> index 132707c8ad..3a0213b39f 100644
> --- a/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist
> +++ b/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist
> @@ -2750,6 +2750,7 @@ GLIBC_2.34 tss_create F
>  GLIBC_2.34 tss_delete F
>  GLIBC_2.34 tss_get F
>  GLIBC_2.34 tss_set F
> +GLIBC_2.35 __memcmpeq F
>  GLIBC_2.4 _IO_fprintf F
>  GLIBC_2.4 _IO_printf F
>  GLIBC_2.4 _IO_sprintf F
> diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist b/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist
> index 0af2be31a0..f57df0234b 100644
> --- a/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist
> +++ b/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist
> @@ -2783,6 +2783,7 @@ GLIBC_2.34 tss_create F
>  GLIBC_2.34 tss_delete F
>  GLIBC_2.34 tss_get F
>  GLIBC_2.34 tss_set F
> +GLIBC_2.35 __memcmpeq F
>  GLIBC_2.4 _IO_fprintf F
>  GLIBC_2.4 _IO_printf F
>  GLIBC_2.4 _IO_sprintf F
> diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc64/be/libc.abilist b/sysdeps/unix/sysv/linux/powerpc/powerpc64/be/libc.abilist
> index cf864632d0..259a0cfc51 100644
> --- a/sysdeps/unix/sysv/linux/powerpc/powerpc64/be/libc.abilist
> +++ b/sysdeps/unix/sysv/linux/powerpc/powerpc64/be/libc.abilist
> @@ -2506,6 +2506,7 @@ GLIBC_2.34 tss_create F
>  GLIBC_2.34 tss_delete F
>  GLIBC_2.34 tss_get F
>  GLIBC_2.34 tss_set F
> +GLIBC_2.35 __memcmpeq F
>  GLIBC_2.4 _IO_fprintf F
>  GLIBC_2.4 _IO_printf F
>  GLIBC_2.4 _IO_sprintf F
> diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc64/le/libc.abilist b/sysdeps/unix/sysv/linux/powerpc/powerpc64/le/libc.abilist
> index d566d675d0..126541daf1 100644
> --- a/sysdeps/unix/sysv/linux/powerpc/powerpc64/le/libc.abilist
> +++ b/sysdeps/unix/sysv/linux/powerpc/powerpc64/le/libc.abilist
> @@ -2808,3 +2808,4 @@ GLIBC_2.34 tss_create F
>  GLIBC_2.34 tss_delete F
>  GLIBC_2.34 tss_get F
>  GLIBC_2.34 tss_set F
> +GLIBC_2.35 __memcmpeq F
> diff --git a/sysdeps/unix/sysv/linux/riscv/rv32/libc.abilist b/sysdeps/unix/sysv/linux/riscv/rv32/libc.abilist
> index c9a7eacb32..05df4d13d2 100644
> --- a/sysdeps/unix/sysv/linux/riscv/rv32/libc.abilist
> +++ b/sysdeps/unix/sysv/linux/riscv/rv32/libc.abilist
> @@ -2375,3 +2375,4 @@ GLIBC_2.34 tss_create F
>  GLIBC_2.34 tss_delete F
>  GLIBC_2.34 tss_get F
>  GLIBC_2.34 tss_set F
> +GLIBC_2.35 __memcmpeq F
> diff --git a/sysdeps/unix/sysv/linux/riscv/rv64/libc.abilist b/sysdeps/unix/sysv/linux/riscv/rv64/libc.abilist
> index 8299131cb2..8e349cbff8 100644
> --- a/sysdeps/unix/sysv/linux/riscv/rv64/libc.abilist
> +++ b/sysdeps/unix/sysv/linux/riscv/rv64/libc.abilist
> @@ -2575,3 +2575,4 @@ GLIBC_2.34 tss_create F
>  GLIBC_2.34 tss_delete F
>  GLIBC_2.34 tss_get F
>  GLIBC_2.34 tss_set F
> +GLIBC_2.35 __memcmpeq F
> diff --git a/sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist b/sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist
> index c3fe78f77f..e9de402766 100644
> --- a/sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist
> +++ b/sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist
> @@ -2748,6 +2748,7 @@ GLIBC_2.34 tss_create F
>  GLIBC_2.34 tss_delete F
>  GLIBC_2.34 tss_get F
>  GLIBC_2.34 tss_set F
> +GLIBC_2.35 __memcmpeq F
>  GLIBC_2.4 _IO_fprintf F
>  GLIBC_2.4 _IO_printf F
>  GLIBC_2.4 _IO_sprintf F
> diff --git a/sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist b/sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist
> index 83e542aa8c..1a010c745d 100644
> --- a/sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist
> +++ b/sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist
> @@ -2543,6 +2543,7 @@ GLIBC_2.34 tss_create F
>  GLIBC_2.34 tss_delete F
>  GLIBC_2.34 tss_get F
>  GLIBC_2.34 tss_set F
> +GLIBC_2.35 __memcmpeq F
>  GLIBC_2.4 _IO_fprintf F
>  GLIBC_2.4 _IO_printf F
>  GLIBC_2.4 _IO_sprintf F
> diff --git a/sysdeps/unix/sysv/linux/sh/be/libc.abilist b/sysdeps/unix/sysv/linux/sh/be/libc.abilist
> index dc502f6833..22ce530975 100644
> --- a/sysdeps/unix/sysv/linux/sh/be/libc.abilist
> +++ b/sysdeps/unix/sysv/linux/sh/be/libc.abilist
> @@ -2603,6 +2603,7 @@ GLIBC_2.34 tss_create F
>  GLIBC_2.34 tss_delete F
>  GLIBC_2.34 tss_get F
>  GLIBC_2.34 tss_set F
> +GLIBC_2.35 __memcmpeq F
>  GLIBC_2.4 __confstr_chk F
>  GLIBC_2.4 __fgets_chk F
>  GLIBC_2.4 __fgets_unlocked_chk F
> diff --git a/sysdeps/unix/sysv/linux/sh/le/libc.abilist b/sysdeps/unix/sysv/linux/sh/le/libc.abilist
> index cba1abb556..960df07b83 100644
> --- a/sysdeps/unix/sysv/linux/sh/le/libc.abilist
> +++ b/sysdeps/unix/sysv/linux/sh/le/libc.abilist
> @@ -2600,6 +2600,7 @@ GLIBC_2.34 tss_create F
>  GLIBC_2.34 tss_delete F
>  GLIBC_2.34 tss_get F
>  GLIBC_2.34 tss_set F
> +GLIBC_2.35 __memcmpeq F
>  GLIBC_2.4 __confstr_chk F
>  GLIBC_2.4 __fgets_chk F
>  GLIBC_2.4 __fgets_unlocked_chk F
> diff --git a/sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist b/sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist
> index d4a516fb47..eedb376f3d 100644
> --- a/sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist
> +++ b/sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist
> @@ -2743,6 +2743,7 @@ GLIBC_2.34 tss_create F
>  GLIBC_2.34 tss_delete F
>  GLIBC_2.34 tss_get F
>  GLIBC_2.34 tss_set F
> +GLIBC_2.35 __memcmpeq F
>  GLIBC_2.4 _IO_fprintf F
>  GLIBC_2.4 _IO_printf F
>  GLIBC_2.4 _IO_sprintf F
> diff --git a/sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist b/sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist
> index 6268875ba3..86e0c92bef 100644
> --- a/sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist
> +++ b/sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist
> @@ -2570,6 +2570,7 @@ GLIBC_2.34 tss_create F
>  GLIBC_2.34 tss_delete F
>  GLIBC_2.34 tss_get F
>  GLIBC_2.34 tss_set F
> +GLIBC_2.35 __memcmpeq F
>  GLIBC_2.4 __confstr_chk F
>  GLIBC_2.4 __fgets_chk F
>  GLIBC_2.4 __fgets_unlocked_chk F
> diff --git a/sysdeps/unix/sysv/linux/x86_64/64/libc.abilist b/sysdeps/unix/sysv/linux/x86_64/64/libc.abilist
> index 095e914b73..5e59d90623 100644
> --- a/sysdeps/unix/sysv/linux/x86_64/64/libc.abilist
> +++ b/sysdeps/unix/sysv/linux/x86_64/64/libc.abilist
> @@ -2521,6 +2521,7 @@ GLIBC_2.34 tss_create F
>  GLIBC_2.34 tss_delete F
>  GLIBC_2.34 tss_get F
>  GLIBC_2.34 tss_set F
> +GLIBC_2.35 __memcmpeq F
>  GLIBC_2.4 __confstr_chk F
>  GLIBC_2.4 __fgets_chk F
>  GLIBC_2.4 __fgets_unlocked_chk F
> diff --git a/sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist b/sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist
> index dd910f7fe9..94412dc134 100644
> --- a/sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist
> +++ b/sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist
> @@ -2627,3 +2627,4 @@ GLIBC_2.34 tss_create F
>  GLIBC_2.34 tss_delete F
>  GLIBC_2.34 tss_get F
>  GLIBC_2.34 tss_set F
> +GLIBC_2.35 __memcmpeq F
> diff --git a/sysdeps/x86_64/memcmp.S b/sysdeps/x86_64/memcmp.S
> index 870e15c5a0..f41ae48006 100644
> --- a/sysdeps/x86_64/memcmp.S
> +++ b/sysdeps/x86_64/memcmp.S
> @@ -358,4 +358,6 @@ END(memcmp)
>
>  #undef bcmp
>  weak_alias (memcmp, bcmp)
> +#undef __memcmpeq
> +weak_alias (memcmp, __memcmpeq)
>  libc_hidden_builtin_def (memcmp)
> diff --git a/sysdeps/x86_64/multiarch/memcmp.c b/sysdeps/x86_64/multiarch/memcmp.c
> index fe725f3563..fe125e0904 100644
> --- a/sysdeps/x86_64/multiarch/memcmp.c
> +++ b/sysdeps/x86_64/multiarch/memcmp.c
> @@ -29,6 +29,8 @@
>  libc_ifunc_redirected (__redirect_memcmp, memcmp, IFUNC_SELECTOR ());
>  # undef bcmp
>  weak_alias (memcmp, bcmp)
> +# undef __memcmpeq
> +weak_alias (memcmp, __memcmpeq)
>
>  # ifdef SHARED
>  __hidden_ver1 (memcmp, __GI_memcmp, __redirect_memcmp)
> --
> 2.25.1
>
Noah Goldstein Oct. 21, 2021, 11:42 p.m. UTC | #2
On Thu, Oct 21, 2021 at 5:50 PM H.J. Lu <hjl.tools@gmail.com> wrote:
>
> On Thu, Oct 21, 2021 at 3:38 PM Noah Goldstein <goldstein.w.n@gmail.com> wrote:
> >
> > No bug.
> >
> > This commit adds support for __memcmpeq() as a new ABI for all
> > targets. In this commit __memcmpeq() is implemented only as an alias
> > to the corresponding targets memcmp() implementation. __memcmpeq() is
> > added as a new symbol starting with GLIBC_2.35 and defined in string.h
> > with comments explaining its behavior. Basic tests that it is callable
> > and works where added in string/tester.c
> >
> > As discussed in the proposal "Add new ABI '__memcmpeq()' to libc"
> > __memcmpeq() is essentially a reserved namespace for bcmp(). The means
> > is shares the same specifications as memcmp() except the return value
> > for non-equal byte sequences is any non-zero value. This is less
> > strict than memcmp()'s return value specification and can be better
> > optimized when a boolean return is all that is needed.
> >
> > __memcmpeq() is meant to only be called by compilers if they can prove
> > that the return value of a memcmp() call is only used for its boolean
> > value.
> >
> > All tests in string/tester.c passed. As well build succeeds on
> > x86_64-linux-gnu target.
> > ---
> >  string/Versions                                  |  3 +++
> >  string/memcmp.c                                  |  2 ++
> >  string/string.h                                  | 16 ++++++++++++++++
> >  string/tester.c                                  | 16 ++++++++++++++++
> >  sysdeps/aarch64/memcmp.S                         |  2 ++
> >  sysdeps/csky/abiv2/memcmp.S                      |  1 +
> >  sysdeps/i386/i686/memcmp.S                       |  2 ++
> >  sysdeps/i386/i686/multiarch/memcmp.c             |  1 +
> >  sysdeps/i386/memcmp.S                            |  2 ++
> >  sysdeps/ia64/memcmp.S                            |  1 +
> >  sysdeps/mach/hurd/i386/libc.abilist              |  1 +
> >  sysdeps/powerpc/powerpc32/405/memcmp.S           |  1 +
> >  sysdeps/powerpc/powerpc32/power4/memcmp.S        |  1 +
> >  sysdeps/powerpc/powerpc32/power7/memcmp.S        |  1 +
> >  sysdeps/powerpc/powerpc64/le/power10/memcmp.S    |  1 +
> >  sysdeps/powerpc/powerpc64/power4/memcmp.S        |  1 +
> >  sysdeps/powerpc/powerpc64/power7/memcmp.S        |  1 +
> >  sysdeps/powerpc/powerpc64/power8/memcmp.S        |  1 +
> >  sysdeps/s390/memcmp-z900.S                       |  1 +
> >  sysdeps/s390/memcmp.c                            |  1 +
> >  sysdeps/sparc/sparc64/memcmp.S                   |  2 ++
> >  sysdeps/unix/sysv/linux/aarch64/libc.abilist     |  1 +
> >  sysdeps/unix/sysv/linux/alpha/libc.abilist       |  1 +
> >  sysdeps/unix/sysv/linux/arc/libc.abilist         |  1 +
> >  sysdeps/unix/sysv/linux/arm/be/libc.abilist      |  1 +
> >  sysdeps/unix/sysv/linux/arm/le/libc.abilist      |  1 +
> >  sysdeps/unix/sysv/linux/csky/libc.abilist        |  1 +
> >  sysdeps/unix/sysv/linux/hppa/libc.abilist        |  1 +
> >  sysdeps/unix/sysv/linux/i386/libc.abilist        |  1 +
> >  sysdeps/unix/sysv/linux/ia64/libc.abilist        |  1 +
> >  .../unix/sysv/linux/m68k/coldfire/libc.abilist   |  1 +
> >  sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist |  1 +
> >  .../unix/sysv/linux/microblaze/be/libc.abilist   |  1 +
> >  .../unix/sysv/linux/microblaze/le/libc.abilist   |  1 +
> >  .../unix/sysv/linux/mips/mips32/fpu/libc.abilist |  1 +
> >  .../sysv/linux/mips/mips32/nofpu/libc.abilist    |  1 +
> >  .../unix/sysv/linux/mips/mips64/n32/libc.abilist |  1 +
> >  .../unix/sysv/linux/mips/mips64/n64/libc.abilist |  1 +
> >  sysdeps/unix/sysv/linux/nios2/libc.abilist       |  1 +
> >  .../linux/powerpc/powerpc32/fpu/libc.abilist     |  1 +
> >  .../linux/powerpc/powerpc32/nofpu/libc.abilist   |  1 +
> >  .../sysv/linux/powerpc/powerpc64/be/libc.abilist |  1 +
> >  .../sysv/linux/powerpc/powerpc64/le/libc.abilist |  1 +
> >  sysdeps/unix/sysv/linux/riscv/rv32/libc.abilist  |  1 +
> >  sysdeps/unix/sysv/linux/riscv/rv64/libc.abilist  |  1 +
> >  .../unix/sysv/linux/s390/s390-32/libc.abilist    |  1 +
> >  .../unix/sysv/linux/s390/s390-64/libc.abilist    |  1 +
> >  sysdeps/unix/sysv/linux/sh/be/libc.abilist       |  1 +
> >  sysdeps/unix/sysv/linux/sh/le/libc.abilist       |  1 +
> >  .../unix/sysv/linux/sparc/sparc32/libc.abilist   |  1 +
> >  .../unix/sysv/linux/sparc/sparc64/libc.abilist   |  1 +
> >  sysdeps/unix/sysv/linux/x86_64/64/libc.abilist   |  1 +
> >  sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist  |  1 +
> >  sysdeps/x86_64/memcmp.S                          |  2 ++
> >  sysdeps/x86_64/multiarch/memcmp.c                |  2 ++
> >  55 files changed, 94 insertions(+)
> >
> > diff --git a/string/Versions b/string/Versions
> > index 298ecd401a..864c4cf7a4 100644
> > --- a/string/Versions
> > +++ b/string/Versions
> > @@ -89,4 +89,7 @@ libc {
> >      sigdescr_np; sigabbrev_np;
> >      strerrordesc_np; strerrorname_np;
> >    }
> > +  GLIBC_2.35 {
> > +    __memcmpeq;
> > +  }
> >  }
> > diff --git a/string/memcmp.c b/string/memcmp.c
> > index 9b46d7a905..5020be00e0 100644
> > --- a/string/memcmp.c
> > +++ b/string/memcmp.c
> > @@ -358,4 +358,6 @@ libc_hidden_builtin_def(memcmp)
> >  #ifdef weak_alias
> >  # undef bcmp
> >  weak_alias (memcmp, bcmp)
> > +# undef __memcmpeq
> > +weak_alias (memcmp, __memcmpeq)
> >  #endif
> > diff --git a/string/string.h b/string/string.h
> > index b1b083edce..e70feeaeea 100644
> > --- a/string/string.h
> > +++ b/string/string.h
> > @@ -64,6 +64,22 @@ extern void *memset (void *__s, int __c, size_t __n) __THROW __nonnull ((1));
> >  extern int memcmp (const void *__s1, const void *__s2, size_t __n)
> >       __THROW __attribute_pure__ __nonnull ((1, 2));
> >
> > +/* Compare N bytes of S1 and S2.  Return zero if S1 and S2 are equal.
> > +   Return some non-zero value otherwise.
> > +
> > +   Essentially __memcmpeq has the exact same semantics as memcmp
> > +   except the return value is less constrained.  memcmp is always a
> > +   correct implementation of __memcmpeq.  As well !!memcmp, -memcmp,
> > +   or bcmp are correct implementations.
> > +
> > +   __memcmpeq is meant to be used by compilers when memcmp return is
> > +   only used for its bolean value.
> > +
> > +   __memcmpeq is declared only for use by compilers.  Programs should
> > +   continue to use memcmp.  */
> > +extern int __memcmpeq (const void *__s1, const void *__s2, size_t __n)
> > +     __THROW __attribute_pure__ __nonnull ((1, 2));
> > +
> >  /* Search N bytes of S for C.  */
> >  #ifdef __CORRECT_ISO_CPP_STRING_H_PROTO
> >  extern "C++"
> > diff --git a/string/tester.c b/string/tester.c
> > index 778160ae6e..605b3f00f9 100644
> > --- a/string/tester.c
> > +++ b/string/tester.c
> > @@ -1449,6 +1449,19 @@ test_bcmp (void)
> >    check(bcmp("abc", "def", 0) == 0, 8);        /* Zero count. */
> >  }
> >
> > +static void
> > +test_memcmpeq (void)
> > +{
> > +  it = "__memcmpeq";
> > +  check (__memcmpeq ("a", "a", 1) == 0, 1); /* Identity.  */
> > +  check (__memcmpeq ("abc", "abc", 3) == 0, 2); /* Multicharacter.  */
> > +  check (__memcmpeq ("abcd", "abce", 4) != 0, 3); /* Honestly unequal.  */
> > +  check (__memcmpeq ("abce", "abcd", 4) != 0, 4);
> > +  check (__memcmpeq ("alph", "beta", 4) != 0, 5);
> > +  check (__memcmpeq ("abce", "abcd", 3) == 0, 6); /* Count limited.  */
> > +  check (__memcmpeq ("abc", "def", 0) == 0, 8); /* Zero count.  */
> > +}
> > +
> >  static void
> >  test_strerror (void)
> >  {
> > @@ -1611,6 +1624,9 @@ main (void)
> >    /* bcmp - somewhat like memcmp.  */
> >    test_bcmp ();
> >
> > +  /* __memcmpeq - somewhat like memcmp.  */
> > +  test_memcmpeq ();
> > +
> >    /* strndup.  */
> >    test_strndup ();
> >
> > diff --git a/sysdeps/aarch64/memcmp.S b/sysdeps/aarch64/memcmp.S
> > index c1937f6f5c..bc932eff2a 100644
> > --- a/sysdeps/aarch64/memcmp.S
> > +++ b/sysdeps/aarch64/memcmp.S
> > @@ -177,4 +177,6 @@ L(ret_0):
> >  END (memcmp)
> >  #undef bcmp
> >  weak_alias (memcmp, bcmp)
> > +#undef __memcmpeq
> > +weak_alias (memcmp, __memcmpeq)
>
> Can we use strong_alias for __memcmpeq?

Think we can but not sure if its needed or we should.
>
> >  libc_hidden_builtin_def (memcmp)
> > diff --git a/sysdeps/csky/abiv2/memcmp.S b/sysdeps/csky/abiv2/memcmp.S
> > index 1560387618..d61fca0f29 100644
> > --- a/sysdeps/csky/abiv2/memcmp.S
> > +++ b/sysdeps/csky/abiv2/memcmp.S
> > @@ -138,5 +138,6 @@ ENTRY (memcmp)
> >         br      .L_s1_aligned
> >  END (memcmp)
> >  weak_alias (memcmp, bcmp)
> > +weak_alias (memcmp, __memcmpeq)
> >  libc_hidden_def (memcmp)
> >  .weak memcmp
> > diff --git a/sysdeps/i386/i686/memcmp.S b/sysdeps/i386/i686/memcmp.S
> > index b26b124fad..0194f8deab 100644
> > --- a/sysdeps/i386/i686/memcmp.S
> > +++ b/sysdeps/i386/i686/memcmp.S
> > @@ -405,4 +405,6 @@ L(table_32bytes) :
> >
> >  #undef bcmp
> >  weak_alias (memcmp, bcmp)
> > +#undef __memcmpeq
> > +weak_alias (memcmp, __memcmpeq)
> >  libc_hidden_builtin_def (memcmp)
> > diff --git a/sysdeps/i386/i686/multiarch/memcmp.c b/sysdeps/i386/i686/multiarch/memcmp.c
> > index 6e058a8857..956fc8e601 100644
> > --- a/sysdeps/i386/i686/multiarch/memcmp.c
> > +++ b/sysdeps/i386/i686/multiarch/memcmp.c
> > @@ -29,4 +29,5 @@
> >  libc_ifunc_redirected (__redirect_memcmp, memcmp, IFUNC_SELECTOR ());
> >
> >  weak_alias (memcmp, bcmp)
> > +weak_alias (memcmp, __memcmpeq)
> >  #endif
> > diff --git a/sysdeps/i386/memcmp.S b/sysdeps/i386/memcmp.S
> > index 1f212b0f6d..18e225f963 100644
> > --- a/sysdeps/i386/memcmp.S
> > +++ b/sysdeps/i386/memcmp.S
> > @@ -70,4 +70,6 @@ END (memcmp)
> >
> >  #undef bcmp
> >  weak_alias (memcmp, bcmp)
> > +#undef __memcmpeq
> > +weak_alias (memcmp, __memcmpeq)
> >  libc_hidden_builtin_def (memcmp)
> > diff --git a/sysdeps/ia64/memcmp.S b/sysdeps/ia64/memcmp.S
> > index 97539c23fd..4488e0eba4 100644
> > --- a/sysdeps/ia64/memcmp.S
> > +++ b/sysdeps/ia64/memcmp.S
> > @@ -160,4 +160,5 @@ ENTRY(memcmp)
> >  END(memcmp)
> >
> >  weak_alias (memcmp, bcmp)
> > +weak_alias (memcmp, __memcmpeq)
> >  libc_hidden_builtin_def (memcmp)
> > diff --git a/sysdeps/mach/hurd/i386/libc.abilist b/sysdeps/mach/hurd/i386/libc.abilist
> > index c5da10a0cd..e849d6fa35 100644
> > --- a/sysdeps/mach/hurd/i386/libc.abilist
> > +++ b/sysdeps/mach/hurd/i386/libc.abilist
> > @@ -2285,6 +2285,7 @@ GLIBC_2.34 res_send F
> >  GLIBC_2.34 shm_open F
> >  GLIBC_2.34 shm_unlink F
> >  GLIBC_2.34 timespec_getres F
> > +GLIBC_2.35 __memcmpeq F
> >  GLIBC_2.4 __confstr_chk F
> >  GLIBC_2.4 __fgets_chk F
> >  GLIBC_2.4 __fgets_unlocked_chk F
> > diff --git a/sysdeps/powerpc/powerpc32/405/memcmp.S b/sysdeps/powerpc/powerpc32/405/memcmp.S
> > index 6a6a54d90f..e8b1b6c9bd 100644
> > --- a/sysdeps/powerpc/powerpc32/405/memcmp.S
> > +++ b/sysdeps/powerpc/powerpc32/405/memcmp.S
> > @@ -126,3 +126,4 @@ L(st2):
> >  END (memcmp)
> >  libc_hidden_builtin_def (memcmp)
> >  weak_alias (memcmp,bcmp)
> > +weak_alias (memcmp, __memcmpeq)
> > diff --git a/sysdeps/powerpc/powerpc32/power4/memcmp.S b/sysdeps/powerpc/powerpc32/power4/memcmp.S
> > index 814d2f211d..e4dde875bb 100644
> > --- a/sysdeps/powerpc/powerpc32/power4/memcmp.S
> > +++ b/sysdeps/powerpc/powerpc32/power4/memcmp.S
> > @@ -1373,3 +1373,4 @@ END (memcmp)
> >
> >  libc_hidden_builtin_def (memcmp)
> >  weak_alias (memcmp, bcmp)
> > +weak_alias (memcmp, __memcmpeq)
> > diff --git a/sysdeps/powerpc/powerpc32/power7/memcmp.S b/sysdeps/powerpc/powerpc32/power7/memcmp.S
> > index 8a19953e2d..e60a62fc86 100644
> > --- a/sysdeps/powerpc/powerpc32/power7/memcmp.S
> > +++ b/sysdeps/powerpc/powerpc32/power7/memcmp.S
> > @@ -1373,3 +1373,4 @@ END (memcmp)
> >
> >  libc_hidden_builtin_def (memcmp)
> >  weak_alias (memcmp, bcmp)
> > +weak_alias (memcmp, __memcmpeq)
> > diff --git a/sysdeps/powerpc/powerpc64/le/power10/memcmp.S b/sysdeps/powerpc/powerpc64/le/power10/memcmp.S
> > index 52f244e7e7..c7fe8047ca 100644
> > --- a/sysdeps/powerpc/powerpc64/le/power10/memcmp.S
> > +++ b/sysdeps/powerpc/powerpc64/le/power10/memcmp.S
> > @@ -177,3 +177,4 @@ L(tail8):
> >  END (MEMCMP)
> >  libc_hidden_builtin_def (memcmp)
> >  weak_alias (memcmp, bcmp)
> > +weak_alias (memcmp, __memcmpeq)
> > diff --git a/sysdeps/powerpc/powerpc64/power4/memcmp.S b/sysdeps/powerpc/powerpc64/power4/memcmp.S
> > index dc1be3a0d8..4ab4a90496 100644
> > --- a/sysdeps/powerpc/powerpc64/power4/memcmp.S
> > +++ b/sysdeps/powerpc/powerpc64/power4/memcmp.S
> > @@ -1374,3 +1374,4 @@ L(duzeroLength):
> >  END (MEMCMP)
> >  libc_hidden_builtin_def (memcmp)
> >  weak_alias (memcmp, bcmp)
> > +weak_alias (memcmp, __memcmpeq)
> > diff --git a/sysdeps/powerpc/powerpc64/power7/memcmp.S b/sysdeps/powerpc/powerpc64/power7/memcmp.S
> > index bc034a55bc..b541978b5f 100644
> > --- a/sysdeps/powerpc/powerpc64/power7/memcmp.S
> > +++ b/sysdeps/powerpc/powerpc64/power7/memcmp.S
> > @@ -1059,3 +1059,4 @@ L(duzeroLength):
> >  END (MEMCMP)
> >  libc_hidden_builtin_def (memcmp)
> >  weak_alias (memcmp, bcmp)
> > +weak_alias (memcmp, __memcmpeq)
> > diff --git a/sysdeps/powerpc/powerpc64/power8/memcmp.S b/sysdeps/powerpc/powerpc64/power8/memcmp.S
> > index b676b09a9b..d4f84a5b6f 100644
> > --- a/sysdeps/powerpc/powerpc64/power8/memcmp.S
> > +++ b/sysdeps/powerpc/powerpc64/power8/memcmp.S
> > @@ -1442,3 +1442,4 @@ L(duzeroLength):
> >  END (MEMCMP)
> >  libc_hidden_builtin_def (memcmp)
> >  weak_alias (memcmp, bcmp)
> > +weak_alias (memcmp, __memcmpeq)
> > diff --git a/sysdeps/s390/memcmp-z900.S b/sysdeps/s390/memcmp-z900.S
> > index 995d52e47d..0942d32814 100644
> > --- a/sysdeps/s390/memcmp-z900.S
> > +++ b/sysdeps/s390/memcmp-z900.S
> > @@ -164,6 +164,7 @@ END(MEMCMP_Z196)
> >     Otherwise see sysdeps/s390/memcmp.c.  */
> >  strong_alias (MEMCMP_DEFAULT, memcmp)
> >  weak_alias (memcmp, bcmp)
> > +weak_alias (memcmp, __memcmpeq)
> >  #endif
> >
> >  #if defined SHARED && IS_IN (libc)
> > diff --git a/sysdeps/s390/memcmp.c b/sysdeps/s390/memcmp.c
> > index 0b4e9da717..475fc45d3a 100644
> > --- a/sysdeps/s390/memcmp.c
> > +++ b/sysdeps/s390/memcmp.c
> > @@ -46,4 +46,5 @@ s390_libc_ifunc_expr (__redirect_memcmp, memcmp,
> >                       })
> >                       )
> >  weak_alias (memcmp, bcmp);
> > +weak_alias (memcmp, __memcmpeq)
> >  #endif
> > diff --git a/sysdeps/sparc/sparc64/memcmp.S b/sysdeps/sparc/sparc64/memcmp.S
> > index d8d9ff9b24..edcc19915a 100644
> > --- a/sysdeps/sparc/sparc64/memcmp.S
> > +++ b/sysdeps/sparc/sparc64/memcmp.S
> > @@ -137,4 +137,6 @@ END(memcmp)
> >
> >  #undef bcmp
> >  weak_alias (memcmp, bcmp)
> > +#undef __memcmpeq
> > +weak_alias (memcmp, __memcmpeq)
> >  libc_hidden_builtin_def (memcmp)
> > diff --git a/sysdeps/unix/sysv/linux/aarch64/libc.abilist b/sysdeps/unix/sysv/linux/aarch64/libc.abilist
> > index 21a2e50a88..f227ae6cee 100644
> > --- a/sysdeps/unix/sysv/linux/aarch64/libc.abilist
> > +++ b/sysdeps/unix/sysv/linux/aarch64/libc.abilist
> > @@ -2612,3 +2612,4 @@ GLIBC_2.34 tss_create F
> >  GLIBC_2.34 tss_delete F
> >  GLIBC_2.34 tss_get F
> >  GLIBC_2.34 tss_set F
> > +GLIBC_2.35 __memcmpeq F
> > diff --git a/sysdeps/unix/sysv/linux/alpha/libc.abilist b/sysdeps/unix/sysv/linux/alpha/libc.abilist
> > index a201fd69ba..0ccc3fc73e 100644
> > --- a/sysdeps/unix/sysv/linux/alpha/libc.abilist
> > +++ b/sysdeps/unix/sysv/linux/alpha/libc.abilist
> > @@ -2709,6 +2709,7 @@ GLIBC_2.34 tss_create F
> >  GLIBC_2.34 tss_delete F
> >  GLIBC_2.34 tss_get F
> >  GLIBC_2.34 tss_set F
> > +GLIBC_2.35 __memcmpeq F
> >  GLIBC_2.4 _IO_fprintf F
> >  GLIBC_2.4 _IO_printf F
> >  GLIBC_2.4 _IO_sprintf F
> > diff --git a/sysdeps/unix/sysv/linux/arc/libc.abilist b/sysdeps/unix/sysv/linux/arc/libc.abilist
> > index 2611436937..fd80704787 100644
> > --- a/sysdeps/unix/sysv/linux/arc/libc.abilist
> > +++ b/sysdeps/unix/sysv/linux/arc/libc.abilist
> > @@ -2373,3 +2373,4 @@ GLIBC_2.34 tss_create F
> >  GLIBC_2.34 tss_delete F
> >  GLIBC_2.34 tss_get F
> >  GLIBC_2.34 tss_set F
> > +GLIBC_2.35 __memcmpeq F
> > diff --git a/sysdeps/unix/sysv/linux/arm/be/libc.abilist b/sysdeps/unix/sysv/linux/arm/be/libc.abilist
> > index a426241965..2ae6c58b8a 100644
> > --- a/sysdeps/unix/sysv/linux/arm/be/libc.abilist
> > +++ b/sysdeps/unix/sysv/linux/arm/be/libc.abilist
> > @@ -491,6 +491,7 @@ GLIBC_2.34 tss_create F
> >  GLIBC_2.34 tss_delete F
> >  GLIBC_2.34 tss_get F
> >  GLIBC_2.34 tss_set F
> > +GLIBC_2.35 __memcmpeq F
> >  GLIBC_2.4 _Exit F
> >  GLIBC_2.4 _IO_2_1_stderr_ D 0xa0
> >  GLIBC_2.4 _IO_2_1_stdin_ D 0xa0
> > diff --git a/sysdeps/unix/sysv/linux/arm/le/libc.abilist b/sysdeps/unix/sysv/linux/arm/le/libc.abilist
> > index 02f80418cc..fcfd1e8594 100644
> > --- a/sysdeps/unix/sysv/linux/arm/le/libc.abilist
> > +++ b/sysdeps/unix/sysv/linux/arm/le/libc.abilist
> > @@ -488,6 +488,7 @@ GLIBC_2.34 tss_create F
> >  GLIBC_2.34 tss_delete F
> >  GLIBC_2.34 tss_get F
> >  GLIBC_2.34 tss_set F
> > +GLIBC_2.35 __memcmpeq F
> >  GLIBC_2.4 _Exit F
> >  GLIBC_2.4 _IO_2_1_stderr_ D 0xa0
> >  GLIBC_2.4 _IO_2_1_stdin_ D 0xa0
> > diff --git a/sysdeps/unix/sysv/linux/csky/libc.abilist b/sysdeps/unix/sysv/linux/csky/libc.abilist
> > index b7676eb372..ba034b8541 100644
> > --- a/sysdeps/unix/sysv/linux/csky/libc.abilist
> > +++ b/sysdeps/unix/sysv/linux/csky/libc.abilist
> > @@ -2647,3 +2647,4 @@ GLIBC_2.34 tss_create F
> >  GLIBC_2.34 tss_delete F
> >  GLIBC_2.34 tss_get F
> >  GLIBC_2.34 tss_set F
> > +GLIBC_2.35 __memcmpeq F
> > diff --git a/sysdeps/unix/sysv/linux/hppa/libc.abilist b/sysdeps/unix/sysv/linux/hppa/libc.abilist
> > index f6965c9d95..b7460bec8a 100644
> > --- a/sysdeps/unix/sysv/linux/hppa/libc.abilist
> > +++ b/sysdeps/unix/sysv/linux/hppa/libc.abilist
> > @@ -2596,6 +2596,7 @@ GLIBC_2.34 tss_create F
> >  GLIBC_2.34 tss_delete F
> >  GLIBC_2.34 tss_get F
> >  GLIBC_2.34 tss_set F
> > +GLIBC_2.35 __memcmpeq F
> >  GLIBC_2.4 __confstr_chk F
> >  GLIBC_2.4 __fgets_chk F
> >  GLIBC_2.4 __fgets_unlocked_chk F
> > diff --git a/sysdeps/unix/sysv/linux/i386/libc.abilist b/sysdeps/unix/sysv/linux/i386/libc.abilist
> > index 2e7603d9ed..a4dc341ded 100644
> > --- a/sysdeps/unix/sysv/linux/i386/libc.abilist
> > +++ b/sysdeps/unix/sysv/linux/i386/libc.abilist
> > @@ -2780,6 +2780,7 @@ GLIBC_2.34 tss_create F
> >  GLIBC_2.34 tss_delete F
> >  GLIBC_2.34 tss_get F
> >  GLIBC_2.34 tss_set F
> > +GLIBC_2.35 __memcmpeq F
> >  GLIBC_2.4 __confstr_chk F
> >  GLIBC_2.4 __fgets_chk F
> >  GLIBC_2.4 __fgets_unlocked_chk F
> > diff --git a/sysdeps/unix/sysv/linux/ia64/libc.abilist b/sysdeps/unix/sysv/linux/ia64/libc.abilist
> > index dd3a56d3fe..94b222dbc7 100644
> > --- a/sysdeps/unix/sysv/linux/ia64/libc.abilist
> > +++ b/sysdeps/unix/sysv/linux/ia64/libc.abilist
> > @@ -2547,6 +2547,7 @@ GLIBC_2.34 tss_create F
> >  GLIBC_2.34 tss_delete F
> >  GLIBC_2.34 tss_get F
> >  GLIBC_2.34 tss_set F
> > +GLIBC_2.35 __memcmpeq F
> >  GLIBC_2.4 __confstr_chk F
> >  GLIBC_2.4 __fgets_chk F
> >  GLIBC_2.4 __fgets_unlocked_chk F
> > diff --git a/sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist b/sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist
> > index c1e0ea9c10..12fd3b6310 100644
> > --- a/sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist
> > +++ b/sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist
> > @@ -492,6 +492,7 @@ GLIBC_2.34 tss_create F
> >  GLIBC_2.34 tss_delete F
> >  GLIBC_2.34 tss_get F
> >  GLIBC_2.34 tss_set F
> > +GLIBC_2.35 __memcmpeq F
> >  GLIBC_2.4 _Exit F
> >  GLIBC_2.4 _IO_2_1_stderr_ D 0x98
> >  GLIBC_2.4 _IO_2_1_stdin_ D 0x98
> > diff --git a/sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist b/sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist
> > index 93161048ca..4d2296007a 100644
> > --- a/sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist
> > +++ b/sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist
> > @@ -2723,6 +2723,7 @@ GLIBC_2.34 tss_create F
> >  GLIBC_2.34 tss_delete F
> >  GLIBC_2.34 tss_get F
> >  GLIBC_2.34 tss_set F
> > +GLIBC_2.35 __memcmpeq F
> >  GLIBC_2.4 __confstr_chk F
> >  GLIBC_2.4 __fgets_chk F
> >  GLIBC_2.4 __fgets_unlocked_chk F
> > diff --git a/sysdeps/unix/sysv/linux/microblaze/be/libc.abilist b/sysdeps/unix/sysv/linux/microblaze/be/libc.abilist
> > index 0aaeec8a27..a223278a3d 100644
> > --- a/sysdeps/unix/sysv/linux/microblaze/be/libc.abilist
> > +++ b/sysdeps/unix/sysv/linux/microblaze/be/libc.abilist
> > @@ -2696,3 +2696,4 @@ GLIBC_2.34 tss_create F
> >  GLIBC_2.34 tss_delete F
> >  GLIBC_2.34 tss_get F
> >  GLIBC_2.34 tss_set F
> > +GLIBC_2.35 __memcmpeq F
> > diff --git a/sysdeps/unix/sysv/linux/microblaze/le/libc.abilist b/sysdeps/unix/sysv/linux/microblaze/le/libc.abilist
> > index bec5f456c9..780a4f5b0b 100644
> > --- a/sysdeps/unix/sysv/linux/microblaze/le/libc.abilist
> > +++ b/sysdeps/unix/sysv/linux/microblaze/le/libc.abilist
> > @@ -2693,3 +2693,4 @@ GLIBC_2.34 tss_create F
> >  GLIBC_2.34 tss_delete F
> >  GLIBC_2.34 tss_get F
> >  GLIBC_2.34 tss_set F
> > +GLIBC_2.35 __memcmpeq F
> > diff --git a/sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist b/sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist
> > index 97d2127f78..cd65136062 100644
> > --- a/sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist
> > +++ b/sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist
> > @@ -2688,6 +2688,7 @@ GLIBC_2.34 tss_create F
> >  GLIBC_2.34 tss_delete F
> >  GLIBC_2.34 tss_get F
> >  GLIBC_2.34 tss_set F
> > +GLIBC_2.35 __memcmpeq F
> >  GLIBC_2.4 __confstr_chk F
> >  GLIBC_2.4 __fgets_chk F
> >  GLIBC_2.4 __fgets_unlocked_chk F
> > diff --git a/sysdeps/unix/sysv/linux/mips/mips32/nofpu/libc.abilist b/sysdeps/unix/sysv/linux/mips/mips32/nofpu/libc.abilist
> > index acb0756c11..b5b9902db5 100644
> > --- a/sysdeps/unix/sysv/linux/mips/mips32/nofpu/libc.abilist
> > +++ b/sysdeps/unix/sysv/linux/mips/mips32/nofpu/libc.abilist
> > @@ -2686,6 +2686,7 @@ GLIBC_2.34 tss_create F
> >  GLIBC_2.34 tss_delete F
> >  GLIBC_2.34 tss_get F
> >  GLIBC_2.34 tss_set F
> > +GLIBC_2.35 __memcmpeq F
> >  GLIBC_2.4 __confstr_chk F
> >  GLIBC_2.4 __fgets_chk F
> >  GLIBC_2.4 __fgets_unlocked_chk F
> > diff --git a/sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist b/sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist
> > index ebc21dde1e..57593d5f94 100644
> > --- a/sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist
> > +++ b/sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist
> > @@ -2694,6 +2694,7 @@ GLIBC_2.34 tss_create F
> >  GLIBC_2.34 tss_delete F
> >  GLIBC_2.34 tss_get F
> >  GLIBC_2.34 tss_set F
> > +GLIBC_2.35 __memcmpeq F
> >  GLIBC_2.4 __confstr_chk F
> >  GLIBC_2.4 __fgets_chk F
> >  GLIBC_2.4 __fgets_unlocked_chk F
> > diff --git a/sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist b/sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist
> > index c68f7e3c6c..e944d76bed 100644
> > --- a/sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist
> > +++ b/sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist
> > @@ -2598,6 +2598,7 @@ GLIBC_2.34 tss_create F
> >  GLIBC_2.34 tss_delete F
> >  GLIBC_2.34 tss_get F
> >  GLIBC_2.34 tss_set F
> > +GLIBC_2.35 __memcmpeq F
> >  GLIBC_2.4 __confstr_chk F
> >  GLIBC_2.4 __fgets_chk F
> >  GLIBC_2.4 __fgets_unlocked_chk F
> > diff --git a/sysdeps/unix/sysv/linux/nios2/libc.abilist b/sysdeps/unix/sysv/linux/nios2/libc.abilist
> > index e5b6834f14..8af5a3a90d 100644
> > --- a/sysdeps/unix/sysv/linux/nios2/libc.abilist
> > +++ b/sysdeps/unix/sysv/linux/nios2/libc.abilist
> > @@ -2735,3 +2735,4 @@ GLIBC_2.34 tss_create F
> >  GLIBC_2.34 tss_delete F
> >  GLIBC_2.34 tss_get F
> >  GLIBC_2.34 tss_set F
> > +GLIBC_2.35 __memcmpeq F
> > diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist b/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist
> > index 132707c8ad..3a0213b39f 100644
> > --- a/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist
> > +++ b/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist
> > @@ -2750,6 +2750,7 @@ GLIBC_2.34 tss_create F
> >  GLIBC_2.34 tss_delete F
> >  GLIBC_2.34 tss_get F
> >  GLIBC_2.34 tss_set F
> > +GLIBC_2.35 __memcmpeq F
> >  GLIBC_2.4 _IO_fprintf F
> >  GLIBC_2.4 _IO_printf F
> >  GLIBC_2.4 _IO_sprintf F
> > diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist b/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist
> > index 0af2be31a0..f57df0234b 100644
> > --- a/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist
> > +++ b/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist
> > @@ -2783,6 +2783,7 @@ GLIBC_2.34 tss_create F
> >  GLIBC_2.34 tss_delete F
> >  GLIBC_2.34 tss_get F
> >  GLIBC_2.34 tss_set F
> > +GLIBC_2.35 __memcmpeq F
> >  GLIBC_2.4 _IO_fprintf F
> >  GLIBC_2.4 _IO_printf F
> >  GLIBC_2.4 _IO_sprintf F
> > diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc64/be/libc.abilist b/sysdeps/unix/sysv/linux/powerpc/powerpc64/be/libc.abilist
> > index cf864632d0..259a0cfc51 100644
> > --- a/sysdeps/unix/sysv/linux/powerpc/powerpc64/be/libc.abilist
> > +++ b/sysdeps/unix/sysv/linux/powerpc/powerpc64/be/libc.abilist
> > @@ -2506,6 +2506,7 @@ GLIBC_2.34 tss_create F
> >  GLIBC_2.34 tss_delete F
> >  GLIBC_2.34 tss_get F
> >  GLIBC_2.34 tss_set F
> > +GLIBC_2.35 __memcmpeq F
> >  GLIBC_2.4 _IO_fprintf F
> >  GLIBC_2.4 _IO_printf F
> >  GLIBC_2.4 _IO_sprintf F
> > diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc64/le/libc.abilist b/sysdeps/unix/sysv/linux/powerpc/powerpc64/le/libc.abilist
> > index d566d675d0..126541daf1 100644
> > --- a/sysdeps/unix/sysv/linux/powerpc/powerpc64/le/libc.abilist
> > +++ b/sysdeps/unix/sysv/linux/powerpc/powerpc64/le/libc.abilist
> > @@ -2808,3 +2808,4 @@ GLIBC_2.34 tss_create F
> >  GLIBC_2.34 tss_delete F
> >  GLIBC_2.34 tss_get F
> >  GLIBC_2.34 tss_set F
> > +GLIBC_2.35 __memcmpeq F
> > diff --git a/sysdeps/unix/sysv/linux/riscv/rv32/libc.abilist b/sysdeps/unix/sysv/linux/riscv/rv32/libc.abilist
> > index c9a7eacb32..05df4d13d2 100644
> > --- a/sysdeps/unix/sysv/linux/riscv/rv32/libc.abilist
> > +++ b/sysdeps/unix/sysv/linux/riscv/rv32/libc.abilist
> > @@ -2375,3 +2375,4 @@ GLIBC_2.34 tss_create F
> >  GLIBC_2.34 tss_delete F
> >  GLIBC_2.34 tss_get F
> >  GLIBC_2.34 tss_set F
> > +GLIBC_2.35 __memcmpeq F
> > diff --git a/sysdeps/unix/sysv/linux/riscv/rv64/libc.abilist b/sysdeps/unix/sysv/linux/riscv/rv64/libc.abilist
> > index 8299131cb2..8e349cbff8 100644
> > --- a/sysdeps/unix/sysv/linux/riscv/rv64/libc.abilist
> > +++ b/sysdeps/unix/sysv/linux/riscv/rv64/libc.abilist
> > @@ -2575,3 +2575,4 @@ GLIBC_2.34 tss_create F
> >  GLIBC_2.34 tss_delete F
> >  GLIBC_2.34 tss_get F
> >  GLIBC_2.34 tss_set F
> > +GLIBC_2.35 __memcmpeq F
> > diff --git a/sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist b/sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist
> > index c3fe78f77f..e9de402766 100644
> > --- a/sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist
> > +++ b/sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist
> > @@ -2748,6 +2748,7 @@ GLIBC_2.34 tss_create F
> >  GLIBC_2.34 tss_delete F
> >  GLIBC_2.34 tss_get F
> >  GLIBC_2.34 tss_set F
> > +GLIBC_2.35 __memcmpeq F
> >  GLIBC_2.4 _IO_fprintf F
> >  GLIBC_2.4 _IO_printf F
> >  GLIBC_2.4 _IO_sprintf F
> > diff --git a/sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist b/sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist
> > index 83e542aa8c..1a010c745d 100644
> > --- a/sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist
> > +++ b/sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist
> > @@ -2543,6 +2543,7 @@ GLIBC_2.34 tss_create F
> >  GLIBC_2.34 tss_delete F
> >  GLIBC_2.34 tss_get F
> >  GLIBC_2.34 tss_set F
> > +GLIBC_2.35 __memcmpeq F
> >  GLIBC_2.4 _IO_fprintf F
> >  GLIBC_2.4 _IO_printf F
> >  GLIBC_2.4 _IO_sprintf F
> > diff --git a/sysdeps/unix/sysv/linux/sh/be/libc.abilist b/sysdeps/unix/sysv/linux/sh/be/libc.abilist
> > index dc502f6833..22ce530975 100644
> > --- a/sysdeps/unix/sysv/linux/sh/be/libc.abilist
> > +++ b/sysdeps/unix/sysv/linux/sh/be/libc.abilist
> > @@ -2603,6 +2603,7 @@ GLIBC_2.34 tss_create F
> >  GLIBC_2.34 tss_delete F
> >  GLIBC_2.34 tss_get F
> >  GLIBC_2.34 tss_set F
> > +GLIBC_2.35 __memcmpeq F
> >  GLIBC_2.4 __confstr_chk F
> >  GLIBC_2.4 __fgets_chk F
> >  GLIBC_2.4 __fgets_unlocked_chk F
> > diff --git a/sysdeps/unix/sysv/linux/sh/le/libc.abilist b/sysdeps/unix/sysv/linux/sh/le/libc.abilist
> > index cba1abb556..960df07b83 100644
> > --- a/sysdeps/unix/sysv/linux/sh/le/libc.abilist
> > +++ b/sysdeps/unix/sysv/linux/sh/le/libc.abilist
> > @@ -2600,6 +2600,7 @@ GLIBC_2.34 tss_create F
> >  GLIBC_2.34 tss_delete F
> >  GLIBC_2.34 tss_get F
> >  GLIBC_2.34 tss_set F
> > +GLIBC_2.35 __memcmpeq F
> >  GLIBC_2.4 __confstr_chk F
> >  GLIBC_2.4 __fgets_chk F
> >  GLIBC_2.4 __fgets_unlocked_chk F
> > diff --git a/sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist b/sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist
> > index d4a516fb47..eedb376f3d 100644
> > --- a/sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist
> > +++ b/sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist
> > @@ -2743,6 +2743,7 @@ GLIBC_2.34 tss_create F
> >  GLIBC_2.34 tss_delete F
> >  GLIBC_2.34 tss_get F
> >  GLIBC_2.34 tss_set F
> > +GLIBC_2.35 __memcmpeq F
> >  GLIBC_2.4 _IO_fprintf F
> >  GLIBC_2.4 _IO_printf F
> >  GLIBC_2.4 _IO_sprintf F
> > diff --git a/sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist b/sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist
> > index 6268875ba3..86e0c92bef 100644
> > --- a/sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist
> > +++ b/sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist
> > @@ -2570,6 +2570,7 @@ GLIBC_2.34 tss_create F
> >  GLIBC_2.34 tss_delete F
> >  GLIBC_2.34 tss_get F
> >  GLIBC_2.34 tss_set F
> > +GLIBC_2.35 __memcmpeq F
> >  GLIBC_2.4 __confstr_chk F
> >  GLIBC_2.4 __fgets_chk F
> >  GLIBC_2.4 __fgets_unlocked_chk F
> > diff --git a/sysdeps/unix/sysv/linux/x86_64/64/libc.abilist b/sysdeps/unix/sysv/linux/x86_64/64/libc.abilist
> > index 095e914b73..5e59d90623 100644
> > --- a/sysdeps/unix/sysv/linux/x86_64/64/libc.abilist
> > +++ b/sysdeps/unix/sysv/linux/x86_64/64/libc.abilist
> > @@ -2521,6 +2521,7 @@ GLIBC_2.34 tss_create F
> >  GLIBC_2.34 tss_delete F
> >  GLIBC_2.34 tss_get F
> >  GLIBC_2.34 tss_set F
> > +GLIBC_2.35 __memcmpeq F
> >  GLIBC_2.4 __confstr_chk F
> >  GLIBC_2.4 __fgets_chk F
> >  GLIBC_2.4 __fgets_unlocked_chk F
> > diff --git a/sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist b/sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist
> > index dd910f7fe9..94412dc134 100644
> > --- a/sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist
> > +++ b/sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist
> > @@ -2627,3 +2627,4 @@ GLIBC_2.34 tss_create F
> >  GLIBC_2.34 tss_delete F
> >  GLIBC_2.34 tss_get F
> >  GLIBC_2.34 tss_set F
> > +GLIBC_2.35 __memcmpeq F
> > diff --git a/sysdeps/x86_64/memcmp.S b/sysdeps/x86_64/memcmp.S
> > index 870e15c5a0..f41ae48006 100644
> > --- a/sysdeps/x86_64/memcmp.S
> > +++ b/sysdeps/x86_64/memcmp.S
> > @@ -358,4 +358,6 @@ END(memcmp)
> >
> >  #undef bcmp
> >  weak_alias (memcmp, bcmp)
> > +#undef __memcmpeq
> > +weak_alias (memcmp, __memcmpeq)
> >  libc_hidden_builtin_def (memcmp)
> > diff --git a/sysdeps/x86_64/multiarch/memcmp.c b/sysdeps/x86_64/multiarch/memcmp.c
> > index fe725f3563..fe125e0904 100644
> > --- a/sysdeps/x86_64/multiarch/memcmp.c
> > +++ b/sysdeps/x86_64/multiarch/memcmp.c
> > @@ -29,6 +29,8 @@
> >  libc_ifunc_redirected (__redirect_memcmp, memcmp, IFUNC_SELECTOR ());
> >  # undef bcmp
> >  weak_alias (memcmp, bcmp)
> > +# undef __memcmpeq
> > +weak_alias (memcmp, __memcmpeq)
> >
> >  # ifdef SHARED
> >  __hidden_ver1 (memcmp, __GI_memcmp, __redirect_memcmp)
> > --
> > 2.25.1
> >
>
>
> --
> H.J.
H.J. Lu Oct. 22, 2021, 2:38 a.m. UTC | #3
On Thu, Oct 21, 2021 at 4:42 PM Noah Goldstein <goldstein.w.n@gmail.com> wrote:
>
> On Thu, Oct 21, 2021 at 5:50 PM H.J. Lu <hjl.tools@gmail.com> wrote:
> >
> > On Thu, Oct 21, 2021 at 3:38 PM Noah Goldstein <goldstein.w.n@gmail.com> wrote:
> > >
> > > No bug.
> > >
> > > This commit adds support for __memcmpeq() as a new ABI for all
> > > targets. In this commit __memcmpeq() is implemented only as an alias
> > > to the corresponding targets memcmp() implementation. __memcmpeq() is
> > > added as a new symbol starting with GLIBC_2.35 and defined in string.h
> > > with comments explaining its behavior. Basic tests that it is callable
> > > and works where added in string/tester.c
> > >
> > > As discussed in the proposal "Add new ABI '__memcmpeq()' to libc"
> > > __memcmpeq() is essentially a reserved namespace for bcmp(). The means
> > > is shares the same specifications as memcmp() except the return value
> > > for non-equal byte sequences is any non-zero value. This is less
> > > strict than memcmp()'s return value specification and can be better
> > > optimized when a boolean return is all that is needed.
> > >
> > > __memcmpeq() is meant to only be called by compilers if they can prove
> > > that the return value of a memcmp() call is only used for its boolean
> > > value.
> > >
> > > All tests in string/tester.c passed. As well build succeeds on
> > > x86_64-linux-gnu target.
> > > ---
> > >  string/Versions                                  |  3 +++
> > >  string/memcmp.c                                  |  2 ++
> > >  string/string.h                                  | 16 ++++++++++++++++
> > >  string/tester.c                                  | 16 ++++++++++++++++
> > >  sysdeps/aarch64/memcmp.S                         |  2 ++
> > >  sysdeps/csky/abiv2/memcmp.S                      |  1 +
> > >  sysdeps/i386/i686/memcmp.S                       |  2 ++
> > >  sysdeps/i386/i686/multiarch/memcmp.c             |  1 +
> > >  sysdeps/i386/memcmp.S                            |  2 ++
> > >  sysdeps/ia64/memcmp.S                            |  1 +
> > >  sysdeps/mach/hurd/i386/libc.abilist              |  1 +
> > >  sysdeps/powerpc/powerpc32/405/memcmp.S           |  1 +
> > >  sysdeps/powerpc/powerpc32/power4/memcmp.S        |  1 +
> > >  sysdeps/powerpc/powerpc32/power7/memcmp.S        |  1 +
> > >  sysdeps/powerpc/powerpc64/le/power10/memcmp.S    |  1 +
> > >  sysdeps/powerpc/powerpc64/power4/memcmp.S        |  1 +
> > >  sysdeps/powerpc/powerpc64/power7/memcmp.S        |  1 +
> > >  sysdeps/powerpc/powerpc64/power8/memcmp.S        |  1 +
> > >  sysdeps/s390/memcmp-z900.S                       |  1 +
> > >  sysdeps/s390/memcmp.c                            |  1 +
> > >  sysdeps/sparc/sparc64/memcmp.S                   |  2 ++
> > >  sysdeps/unix/sysv/linux/aarch64/libc.abilist     |  1 +
> > >  sysdeps/unix/sysv/linux/alpha/libc.abilist       |  1 +
> > >  sysdeps/unix/sysv/linux/arc/libc.abilist         |  1 +
> > >  sysdeps/unix/sysv/linux/arm/be/libc.abilist      |  1 +
> > >  sysdeps/unix/sysv/linux/arm/le/libc.abilist      |  1 +
> > >  sysdeps/unix/sysv/linux/csky/libc.abilist        |  1 +
> > >  sysdeps/unix/sysv/linux/hppa/libc.abilist        |  1 +
> > >  sysdeps/unix/sysv/linux/i386/libc.abilist        |  1 +
> > >  sysdeps/unix/sysv/linux/ia64/libc.abilist        |  1 +
> > >  .../unix/sysv/linux/m68k/coldfire/libc.abilist   |  1 +
> > >  sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist |  1 +
> > >  .../unix/sysv/linux/microblaze/be/libc.abilist   |  1 +
> > >  .../unix/sysv/linux/microblaze/le/libc.abilist   |  1 +
> > >  .../unix/sysv/linux/mips/mips32/fpu/libc.abilist |  1 +
> > >  .../sysv/linux/mips/mips32/nofpu/libc.abilist    |  1 +
> > >  .../unix/sysv/linux/mips/mips64/n32/libc.abilist |  1 +
> > >  .../unix/sysv/linux/mips/mips64/n64/libc.abilist |  1 +
> > >  sysdeps/unix/sysv/linux/nios2/libc.abilist       |  1 +
> > >  .../linux/powerpc/powerpc32/fpu/libc.abilist     |  1 +
> > >  .../linux/powerpc/powerpc32/nofpu/libc.abilist   |  1 +
> > >  .../sysv/linux/powerpc/powerpc64/be/libc.abilist |  1 +
> > >  .../sysv/linux/powerpc/powerpc64/le/libc.abilist |  1 +
> > >  sysdeps/unix/sysv/linux/riscv/rv32/libc.abilist  |  1 +
> > >  sysdeps/unix/sysv/linux/riscv/rv64/libc.abilist  |  1 +
> > >  .../unix/sysv/linux/s390/s390-32/libc.abilist    |  1 +
> > >  .../unix/sysv/linux/s390/s390-64/libc.abilist    |  1 +
> > >  sysdeps/unix/sysv/linux/sh/be/libc.abilist       |  1 +
> > >  sysdeps/unix/sysv/linux/sh/le/libc.abilist       |  1 +
> > >  .../unix/sysv/linux/sparc/sparc32/libc.abilist   |  1 +
> > >  .../unix/sysv/linux/sparc/sparc64/libc.abilist   |  1 +
> > >  sysdeps/unix/sysv/linux/x86_64/64/libc.abilist   |  1 +
> > >  sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist  |  1 +
> > >  sysdeps/x86_64/memcmp.S                          |  2 ++
> > >  sysdeps/x86_64/multiarch/memcmp.c                |  2 ++
> > >  55 files changed, 94 insertions(+)
> > >
> > > diff --git a/string/Versions b/string/Versions
> > > index 298ecd401a..864c4cf7a4 100644
> > > --- a/string/Versions
> > > +++ b/string/Versions
> > > @@ -89,4 +89,7 @@ libc {
> > >      sigdescr_np; sigabbrev_np;
> > >      strerrordesc_np; strerrorname_np;
> > >    }
> > > +  GLIBC_2.35 {
> > > +    __memcmpeq;
> > > +  }
> > >  }
> > > diff --git a/string/memcmp.c b/string/memcmp.c
> > > index 9b46d7a905..5020be00e0 100644
> > > --- a/string/memcmp.c
> > > +++ b/string/memcmp.c
> > > @@ -358,4 +358,6 @@ libc_hidden_builtin_def(memcmp)
> > >  #ifdef weak_alias
> > >  # undef bcmp
> > >  weak_alias (memcmp, bcmp)
> > > +# undef __memcmpeq
> > > +weak_alias (memcmp, __memcmpeq)
> > >  #endif
> > > diff --git a/string/string.h b/string/string.h
> > > index b1b083edce..e70feeaeea 100644
> > > --- a/string/string.h
> > > +++ b/string/string.h
> > > @@ -64,6 +64,22 @@ extern void *memset (void *__s, int __c, size_t __n) __THROW __nonnull ((1));
> > >  extern int memcmp (const void *__s1, const void *__s2, size_t __n)
> > >       __THROW __attribute_pure__ __nonnull ((1, 2));
> > >
> > > +/* Compare N bytes of S1 and S2.  Return zero if S1 and S2 are equal.
> > > +   Return some non-zero value otherwise.
> > > +
> > > +   Essentially __memcmpeq has the exact same semantics as memcmp
> > > +   except the return value is less constrained.  memcmp is always a
> > > +   correct implementation of __memcmpeq.  As well !!memcmp, -memcmp,
> > > +   or bcmp are correct implementations.
> > > +
> > > +   __memcmpeq is meant to be used by compilers when memcmp return is
> > > +   only used for its bolean value.
> > > +
> > > +   __memcmpeq is declared only for use by compilers.  Programs should
> > > +   continue to use memcmp.  */
> > > +extern int __memcmpeq (const void *__s1, const void *__s2, size_t __n)
> > > +     __THROW __attribute_pure__ __nonnull ((1, 2));
> > > +
> > >  /* Search N bytes of S for C.  */
> > >  #ifdef __CORRECT_ISO_CPP_STRING_H_PROTO
> > >  extern "C++"
> > > diff --git a/string/tester.c b/string/tester.c
> > > index 778160ae6e..605b3f00f9 100644
> > > --- a/string/tester.c
> > > +++ b/string/tester.c
> > > @@ -1449,6 +1449,19 @@ test_bcmp (void)
> > >    check(bcmp("abc", "def", 0) == 0, 8);        /* Zero count. */
> > >  }
> > >
> > > +static void
> > > +test_memcmpeq (void)
> > > +{
> > > +  it = "__memcmpeq";
> > > +  check (__memcmpeq ("a", "a", 1) == 0, 1); /* Identity.  */
> > > +  check (__memcmpeq ("abc", "abc", 3) == 0, 2); /* Multicharacter.  */
> > > +  check (__memcmpeq ("abcd", "abce", 4) != 0, 3); /* Honestly unequal.  */
> > > +  check (__memcmpeq ("abce", "abcd", 4) != 0, 4);
> > > +  check (__memcmpeq ("alph", "beta", 4) != 0, 5);
> > > +  check (__memcmpeq ("abce", "abcd", 3) == 0, 6); /* Count limited.  */
> > > +  check (__memcmpeq ("abc", "def", 0) == 0, 8); /* Zero count.  */
> > > +}
> > > +
> > >  static void
> > >  test_strerror (void)
> > >  {
> > > @@ -1611,6 +1624,9 @@ main (void)
> > >    /* bcmp - somewhat like memcmp.  */
> > >    test_bcmp ();
> > >
> > > +  /* __memcmpeq - somewhat like memcmp.  */
> > > +  test_memcmpeq ();
> > > +
> > >    /* strndup.  */
> > >    test_strndup ();
> > >
> > > diff --git a/sysdeps/aarch64/memcmp.S b/sysdeps/aarch64/memcmp.S
> > > index c1937f6f5c..bc932eff2a 100644
> > > --- a/sysdeps/aarch64/memcmp.S
> > > +++ b/sysdeps/aarch64/memcmp.S
> > > @@ -177,4 +177,6 @@ L(ret_0):
> > >  END (memcmp)
> > >  #undef bcmp
> > >  weak_alias (memcmp, bcmp)
> > > +#undef __memcmpeq
> > > +weak_alias (memcmp, __memcmpeq)
> >
> > Can we use strong_alias for __memcmpeq?
>
> Think we can but not sure if its needed or we should.

__memcmpeq shouldn't have STB_WEAK binding since it
shouldn't be preempted.
Noah Goldstein Oct. 22, 2021, 4:04 a.m. UTC | #4
On Thu, Oct 21, 2021 at 9:38 PM H.J. Lu <hjl.tools@gmail.com> wrote:
>
> On Thu, Oct 21, 2021 at 4:42 PM Noah Goldstein <goldstein.w.n@gmail.com> wrote:
> >
> > On Thu, Oct 21, 2021 at 5:50 PM H.J. Lu <hjl.tools@gmail.com> wrote:
> > >
> > > On Thu, Oct 21, 2021 at 3:38 PM Noah Goldstein <goldstein.w.n@gmail.com> wrote:
> > > >
> > > > No bug.
> > > >
> > > > This commit adds support for __memcmpeq() as a new ABI for all
> > > > targets. In this commit __memcmpeq() is implemented only as an alias
> > > > to the corresponding targets memcmp() implementation. __memcmpeq() is
> > > > added as a new symbol starting with GLIBC_2.35 and defined in string.h
> > > > with comments explaining its behavior. Basic tests that it is callable
> > > > and works where added in string/tester.c
> > > >
> > > > As discussed in the proposal "Add new ABI '__memcmpeq()' to libc"
> > > > __memcmpeq() is essentially a reserved namespace for bcmp(). The means
> > > > is shares the same specifications as memcmp() except the return value
> > > > for non-equal byte sequences is any non-zero value. This is less
> > > > strict than memcmp()'s return value specification and can be better
> > > > optimized when a boolean return is all that is needed.
> > > >
> > > > __memcmpeq() is meant to only be called by compilers if they can prove
> > > > that the return value of a memcmp() call is only used for its boolean
> > > > value.
> > > >
> > > > All tests in string/tester.c passed. As well build succeeds on
> > > > x86_64-linux-gnu target.
> > > > ---
> > > >  string/Versions                                  |  3 +++
> > > >  string/memcmp.c                                  |  2 ++
> > > >  string/string.h                                  | 16 ++++++++++++++++
> > > >  string/tester.c                                  | 16 ++++++++++++++++
> > > >  sysdeps/aarch64/memcmp.S                         |  2 ++
> > > >  sysdeps/csky/abiv2/memcmp.S                      |  1 +
> > > >  sysdeps/i386/i686/memcmp.S                       |  2 ++
> > > >  sysdeps/i386/i686/multiarch/memcmp.c             |  1 +
> > > >  sysdeps/i386/memcmp.S                            |  2 ++
> > > >  sysdeps/ia64/memcmp.S                            |  1 +
> > > >  sysdeps/mach/hurd/i386/libc.abilist              |  1 +
> > > >  sysdeps/powerpc/powerpc32/405/memcmp.S           |  1 +
> > > >  sysdeps/powerpc/powerpc32/power4/memcmp.S        |  1 +
> > > >  sysdeps/powerpc/powerpc32/power7/memcmp.S        |  1 +
> > > >  sysdeps/powerpc/powerpc64/le/power10/memcmp.S    |  1 +
> > > >  sysdeps/powerpc/powerpc64/power4/memcmp.S        |  1 +
> > > >  sysdeps/powerpc/powerpc64/power7/memcmp.S        |  1 +
> > > >  sysdeps/powerpc/powerpc64/power8/memcmp.S        |  1 +
> > > >  sysdeps/s390/memcmp-z900.S                       |  1 +
> > > >  sysdeps/s390/memcmp.c                            |  1 +
> > > >  sysdeps/sparc/sparc64/memcmp.S                   |  2 ++
> > > >  sysdeps/unix/sysv/linux/aarch64/libc.abilist     |  1 +
> > > >  sysdeps/unix/sysv/linux/alpha/libc.abilist       |  1 +
> > > >  sysdeps/unix/sysv/linux/arc/libc.abilist         |  1 +
> > > >  sysdeps/unix/sysv/linux/arm/be/libc.abilist      |  1 +
> > > >  sysdeps/unix/sysv/linux/arm/le/libc.abilist      |  1 +
> > > >  sysdeps/unix/sysv/linux/csky/libc.abilist        |  1 +
> > > >  sysdeps/unix/sysv/linux/hppa/libc.abilist        |  1 +
> > > >  sysdeps/unix/sysv/linux/i386/libc.abilist        |  1 +
> > > >  sysdeps/unix/sysv/linux/ia64/libc.abilist        |  1 +
> > > >  .../unix/sysv/linux/m68k/coldfire/libc.abilist   |  1 +
> > > >  sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist |  1 +
> > > >  .../unix/sysv/linux/microblaze/be/libc.abilist   |  1 +
> > > >  .../unix/sysv/linux/microblaze/le/libc.abilist   |  1 +
> > > >  .../unix/sysv/linux/mips/mips32/fpu/libc.abilist |  1 +
> > > >  .../sysv/linux/mips/mips32/nofpu/libc.abilist    |  1 +
> > > >  .../unix/sysv/linux/mips/mips64/n32/libc.abilist |  1 +
> > > >  .../unix/sysv/linux/mips/mips64/n64/libc.abilist |  1 +
> > > >  sysdeps/unix/sysv/linux/nios2/libc.abilist       |  1 +
> > > >  .../linux/powerpc/powerpc32/fpu/libc.abilist     |  1 +
> > > >  .../linux/powerpc/powerpc32/nofpu/libc.abilist   |  1 +
> > > >  .../sysv/linux/powerpc/powerpc64/be/libc.abilist |  1 +
> > > >  .../sysv/linux/powerpc/powerpc64/le/libc.abilist |  1 +
> > > >  sysdeps/unix/sysv/linux/riscv/rv32/libc.abilist  |  1 +
> > > >  sysdeps/unix/sysv/linux/riscv/rv64/libc.abilist  |  1 +
> > > >  .../unix/sysv/linux/s390/s390-32/libc.abilist    |  1 +
> > > >  .../unix/sysv/linux/s390/s390-64/libc.abilist    |  1 +
> > > >  sysdeps/unix/sysv/linux/sh/be/libc.abilist       |  1 +
> > > >  sysdeps/unix/sysv/linux/sh/le/libc.abilist       |  1 +
> > > >  .../unix/sysv/linux/sparc/sparc32/libc.abilist   |  1 +
> > > >  .../unix/sysv/linux/sparc/sparc64/libc.abilist   |  1 +
> > > >  sysdeps/unix/sysv/linux/x86_64/64/libc.abilist   |  1 +
> > > >  sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist  |  1 +
> > > >  sysdeps/x86_64/memcmp.S                          |  2 ++
> > > >  sysdeps/x86_64/multiarch/memcmp.c                |  2 ++
> > > >  55 files changed, 94 insertions(+)
> > > >
> > > > diff --git a/string/Versions b/string/Versions
> > > > index 298ecd401a..864c4cf7a4 100644
> > > > --- a/string/Versions
> > > > +++ b/string/Versions
> > > > @@ -89,4 +89,7 @@ libc {
> > > >      sigdescr_np; sigabbrev_np;
> > > >      strerrordesc_np; strerrorname_np;
> > > >    }
> > > > +  GLIBC_2.35 {
> > > > +    __memcmpeq;
> > > > +  }
> > > >  }
> > > > diff --git a/string/memcmp.c b/string/memcmp.c
> > > > index 9b46d7a905..5020be00e0 100644
> > > > --- a/string/memcmp.c
> > > > +++ b/string/memcmp.c
> > > > @@ -358,4 +358,6 @@ libc_hidden_builtin_def(memcmp)
> > > >  #ifdef weak_alias
> > > >  # undef bcmp
> > > >  weak_alias (memcmp, bcmp)
> > > > +# undef __memcmpeq
> > > > +weak_alias (memcmp, __memcmpeq)
> > > >  #endif
> > > > diff --git a/string/string.h b/string/string.h
> > > > index b1b083edce..e70feeaeea 100644
> > > > --- a/string/string.h
> > > > +++ b/string/string.h
> > > > @@ -64,6 +64,22 @@ extern void *memset (void *__s, int __c, size_t __n) __THROW __nonnull ((1));
> > > >  extern int memcmp (const void *__s1, const void *__s2, size_t __n)
> > > >       __THROW __attribute_pure__ __nonnull ((1, 2));
> > > >
> > > > +/* Compare N bytes of S1 and S2.  Return zero if S1 and S2 are equal.
> > > > +   Return some non-zero value otherwise.
> > > > +
> > > > +   Essentially __memcmpeq has the exact same semantics as memcmp
> > > > +   except the return value is less constrained.  memcmp is always a
> > > > +   correct implementation of __memcmpeq.  As well !!memcmp, -memcmp,
> > > > +   or bcmp are correct implementations.
> > > > +
> > > > +   __memcmpeq is meant to be used by compilers when memcmp return is
> > > > +   only used for its bolean value.
> > > > +
> > > > +   __memcmpeq is declared only for use by compilers.  Programs should
> > > > +   continue to use memcmp.  */
> > > > +extern int __memcmpeq (const void *__s1, const void *__s2, size_t __n)
> > > > +     __THROW __attribute_pure__ __nonnull ((1, 2));
> > > > +
> > > >  /* Search N bytes of S for C.  */
> > > >  #ifdef __CORRECT_ISO_CPP_STRING_H_PROTO
> > > >  extern "C++"
> > > > diff --git a/string/tester.c b/string/tester.c
> > > > index 778160ae6e..605b3f00f9 100644
> > > > --- a/string/tester.c
> > > > +++ b/string/tester.c
> > > > @@ -1449,6 +1449,19 @@ test_bcmp (void)
> > > >    check(bcmp("abc", "def", 0) == 0, 8);        /* Zero count. */
> > > >  }
> > > >
> > > > +static void
> > > > +test_memcmpeq (void)
> > > > +{
> > > > +  it = "__memcmpeq";
> > > > +  check (__memcmpeq ("a", "a", 1) == 0, 1); /* Identity.  */
> > > > +  check (__memcmpeq ("abc", "abc", 3) == 0, 2); /* Multicharacter.  */
> > > > +  check (__memcmpeq ("abcd", "abce", 4) != 0, 3); /* Honestly unequal.  */
> > > > +  check (__memcmpeq ("abce", "abcd", 4) != 0, 4);
> > > > +  check (__memcmpeq ("alph", "beta", 4) != 0, 5);
> > > > +  check (__memcmpeq ("abce", "abcd", 3) == 0, 6); /* Count limited.  */
> > > > +  check (__memcmpeq ("abc", "def", 0) == 0, 8); /* Zero count.  */
> > > > +}
> > > > +
> > > >  static void
> > > >  test_strerror (void)
> > > >  {
> > > > @@ -1611,6 +1624,9 @@ main (void)
> > > >    /* bcmp - somewhat like memcmp.  */
> > > >    test_bcmp ();
> > > >
> > > > +  /* __memcmpeq - somewhat like memcmp.  */
> > > > +  test_memcmpeq ();
> > > > +
> > > >    /* strndup.  */
> > > >    test_strndup ();
> > > >
> > > > diff --git a/sysdeps/aarch64/memcmp.S b/sysdeps/aarch64/memcmp.S
> > > > index c1937f6f5c..bc932eff2a 100644
> > > > --- a/sysdeps/aarch64/memcmp.S
> > > > +++ b/sysdeps/aarch64/memcmp.S
> > > > @@ -177,4 +177,6 @@ L(ret_0):
> > > >  END (memcmp)
> > > >  #undef bcmp
> > > >  weak_alias (memcmp, bcmp)
> > > > +#undef __memcmpeq
> > > > +weak_alias (memcmp, __memcmpeq)
> > >
> > > Can we use strong_alias for __memcmpeq?
> >
> > Think we can but not sure if its needed or we should.
>
> __memcmpeq shouldn't have STB_WEAK binding since it
> shouldn't be preempted.

Got it. Note for x86_64 the patch defined an alias from
memcmp -> memcmpeq in two places.

Onces in sysdeps/x86_64/memcmp.S and once
in sysdeps/x86_64/multiarch/memcmp.c. The one in
memcmp.c is the one that will get the IFUNC selection
so I think that's the one we want to keep but will there
be an issue with ld.so usage of __memcmpeq if there
is no alias in memcmp.S? Should the one in memcmp.S
stay weak maybe?
>
>
> --
> H.J.
diff mbox series

Patch

diff --git a/string/Versions b/string/Versions
index 298ecd401a..864c4cf7a4 100644
--- a/string/Versions
+++ b/string/Versions
@@ -89,4 +89,7 @@  libc {
     sigdescr_np; sigabbrev_np;
     strerrordesc_np; strerrorname_np;
   }
+  GLIBC_2.35 {
+    __memcmpeq;
+  }
 }
diff --git a/string/memcmp.c b/string/memcmp.c
index 9b46d7a905..5020be00e0 100644
--- a/string/memcmp.c
+++ b/string/memcmp.c
@@ -358,4 +358,6 @@  libc_hidden_builtin_def(memcmp)
 #ifdef weak_alias
 # undef bcmp
 weak_alias (memcmp, bcmp)
+# undef __memcmpeq
+weak_alias (memcmp, __memcmpeq)
 #endif
diff --git a/string/string.h b/string/string.h
index b1b083edce..e70feeaeea 100644
--- a/string/string.h
+++ b/string/string.h
@@ -64,6 +64,22 @@  extern void *memset (void *__s, int __c, size_t __n) __THROW __nonnull ((1));
 extern int memcmp (const void *__s1, const void *__s2, size_t __n)
      __THROW __attribute_pure__ __nonnull ((1, 2));
 
+/* Compare N bytes of S1 and S2.  Return zero if S1 and S2 are equal.
+   Return some non-zero value otherwise.
+
+   Essentially __memcmpeq has the exact same semantics as memcmp
+   except the return value is less constrained.  memcmp is always a
+   correct implementation of __memcmpeq.  As well !!memcmp, -memcmp,
+   or bcmp are correct implementations.
+
+   __memcmpeq is meant to be used by compilers when memcmp return is
+   only used for its bolean value.
+
+   __memcmpeq is declared only for use by compilers.  Programs should
+   continue to use memcmp.  */
+extern int __memcmpeq (const void *__s1, const void *__s2, size_t __n)
+     __THROW __attribute_pure__ __nonnull ((1, 2));
+
 /* Search N bytes of S for C.  */
 #ifdef __CORRECT_ISO_CPP_STRING_H_PROTO
 extern "C++"
diff --git a/string/tester.c b/string/tester.c
index 778160ae6e..605b3f00f9 100644
--- a/string/tester.c
+++ b/string/tester.c
@@ -1449,6 +1449,19 @@  test_bcmp (void)
   check(bcmp("abc", "def", 0) == 0, 8);	/* Zero count. */
 }
 
+static void
+test_memcmpeq (void)
+{
+  it = "__memcmpeq";
+  check (__memcmpeq ("a", "a", 1) == 0, 1); /* Identity.  */
+  check (__memcmpeq ("abc", "abc", 3) == 0, 2); /* Multicharacter.  */
+  check (__memcmpeq ("abcd", "abce", 4) != 0, 3); /* Honestly unequal.  */
+  check (__memcmpeq ("abce", "abcd", 4) != 0, 4);
+  check (__memcmpeq ("alph", "beta", 4) != 0, 5);
+  check (__memcmpeq ("abce", "abcd", 3) == 0, 6); /* Count limited.  */
+  check (__memcmpeq ("abc", "def", 0) == 0, 8); /* Zero count.  */
+}
+
 static void
 test_strerror (void)
 {
@@ -1611,6 +1624,9 @@  main (void)
   /* bcmp - somewhat like memcmp.  */
   test_bcmp ();
 
+  /* __memcmpeq - somewhat like memcmp.  */
+  test_memcmpeq ();
+
   /* strndup.  */
   test_strndup ();
 
diff --git a/sysdeps/aarch64/memcmp.S b/sysdeps/aarch64/memcmp.S
index c1937f6f5c..bc932eff2a 100644
--- a/sysdeps/aarch64/memcmp.S
+++ b/sysdeps/aarch64/memcmp.S
@@ -177,4 +177,6 @@  L(ret_0):
 END (memcmp)
 #undef bcmp
 weak_alias (memcmp, bcmp)
+#undef __memcmpeq
+weak_alias (memcmp, __memcmpeq)
 libc_hidden_builtin_def (memcmp)
diff --git a/sysdeps/csky/abiv2/memcmp.S b/sysdeps/csky/abiv2/memcmp.S
index 1560387618..d61fca0f29 100644
--- a/sysdeps/csky/abiv2/memcmp.S
+++ b/sysdeps/csky/abiv2/memcmp.S
@@ -138,5 +138,6 @@  ENTRY (memcmp)
 	br	.L_s1_aligned
 END (memcmp)
 weak_alias (memcmp, bcmp)
+weak_alias (memcmp, __memcmpeq)
 libc_hidden_def (memcmp)
 .weak memcmp
diff --git a/sysdeps/i386/i686/memcmp.S b/sysdeps/i386/i686/memcmp.S
index b26b124fad..0194f8deab 100644
--- a/sysdeps/i386/i686/memcmp.S
+++ b/sysdeps/i386/i686/memcmp.S
@@ -405,4 +405,6 @@  L(table_32bytes) :
 
 #undef bcmp
 weak_alias (memcmp, bcmp)
+#undef __memcmpeq
+weak_alias (memcmp, __memcmpeq)
 libc_hidden_builtin_def (memcmp)
diff --git a/sysdeps/i386/i686/multiarch/memcmp.c b/sysdeps/i386/i686/multiarch/memcmp.c
index 6e058a8857..956fc8e601 100644
--- a/sysdeps/i386/i686/multiarch/memcmp.c
+++ b/sysdeps/i386/i686/multiarch/memcmp.c
@@ -29,4 +29,5 @@ 
 libc_ifunc_redirected (__redirect_memcmp, memcmp, IFUNC_SELECTOR ());
 
 weak_alias (memcmp, bcmp)
+weak_alias (memcmp, __memcmpeq)
 #endif
diff --git a/sysdeps/i386/memcmp.S b/sysdeps/i386/memcmp.S
index 1f212b0f6d..18e225f963 100644
--- a/sysdeps/i386/memcmp.S
+++ b/sysdeps/i386/memcmp.S
@@ -70,4 +70,6 @@  END (memcmp)
 
 #undef bcmp
 weak_alias (memcmp, bcmp)
+#undef __memcmpeq
+weak_alias (memcmp, __memcmpeq)
 libc_hidden_builtin_def (memcmp)
diff --git a/sysdeps/ia64/memcmp.S b/sysdeps/ia64/memcmp.S
index 97539c23fd..4488e0eba4 100644
--- a/sysdeps/ia64/memcmp.S
+++ b/sysdeps/ia64/memcmp.S
@@ -160,4 +160,5 @@  ENTRY(memcmp)
 END(memcmp)
 
 weak_alias (memcmp, bcmp)
+weak_alias (memcmp, __memcmpeq)
 libc_hidden_builtin_def (memcmp)
diff --git a/sysdeps/mach/hurd/i386/libc.abilist b/sysdeps/mach/hurd/i386/libc.abilist
index c5da10a0cd..e849d6fa35 100644
--- a/sysdeps/mach/hurd/i386/libc.abilist
+++ b/sysdeps/mach/hurd/i386/libc.abilist
@@ -2285,6 +2285,7 @@  GLIBC_2.34 res_send F
 GLIBC_2.34 shm_open F
 GLIBC_2.34 shm_unlink F
 GLIBC_2.34 timespec_getres F
+GLIBC_2.35 __memcmpeq F
 GLIBC_2.4 __confstr_chk F
 GLIBC_2.4 __fgets_chk F
 GLIBC_2.4 __fgets_unlocked_chk F
diff --git a/sysdeps/powerpc/powerpc32/405/memcmp.S b/sysdeps/powerpc/powerpc32/405/memcmp.S
index 6a6a54d90f..e8b1b6c9bd 100644
--- a/sysdeps/powerpc/powerpc32/405/memcmp.S
+++ b/sysdeps/powerpc/powerpc32/405/memcmp.S
@@ -126,3 +126,4 @@  L(st2):
 END (memcmp)
 libc_hidden_builtin_def (memcmp)
 weak_alias (memcmp,bcmp)
+weak_alias (memcmp, __memcmpeq)
diff --git a/sysdeps/powerpc/powerpc32/power4/memcmp.S b/sysdeps/powerpc/powerpc32/power4/memcmp.S
index 814d2f211d..e4dde875bb 100644
--- a/sysdeps/powerpc/powerpc32/power4/memcmp.S
+++ b/sysdeps/powerpc/powerpc32/power4/memcmp.S
@@ -1373,3 +1373,4 @@  END (memcmp)
 
 libc_hidden_builtin_def (memcmp)
 weak_alias (memcmp, bcmp)
+weak_alias (memcmp, __memcmpeq)
diff --git a/sysdeps/powerpc/powerpc32/power7/memcmp.S b/sysdeps/powerpc/powerpc32/power7/memcmp.S
index 8a19953e2d..e60a62fc86 100644
--- a/sysdeps/powerpc/powerpc32/power7/memcmp.S
+++ b/sysdeps/powerpc/powerpc32/power7/memcmp.S
@@ -1373,3 +1373,4 @@  END (memcmp)
 
 libc_hidden_builtin_def (memcmp)
 weak_alias (memcmp, bcmp)
+weak_alias (memcmp, __memcmpeq)
diff --git a/sysdeps/powerpc/powerpc64/le/power10/memcmp.S b/sysdeps/powerpc/powerpc64/le/power10/memcmp.S
index 52f244e7e7..c7fe8047ca 100644
--- a/sysdeps/powerpc/powerpc64/le/power10/memcmp.S
+++ b/sysdeps/powerpc/powerpc64/le/power10/memcmp.S
@@ -177,3 +177,4 @@  L(tail8):
 END (MEMCMP)
 libc_hidden_builtin_def (memcmp)
 weak_alias (memcmp, bcmp)
+weak_alias (memcmp, __memcmpeq)
diff --git a/sysdeps/powerpc/powerpc64/power4/memcmp.S b/sysdeps/powerpc/powerpc64/power4/memcmp.S
index dc1be3a0d8..4ab4a90496 100644
--- a/sysdeps/powerpc/powerpc64/power4/memcmp.S
+++ b/sysdeps/powerpc/powerpc64/power4/memcmp.S
@@ -1374,3 +1374,4 @@  L(duzeroLength):
 END (MEMCMP)
 libc_hidden_builtin_def (memcmp)
 weak_alias (memcmp, bcmp)
+weak_alias (memcmp, __memcmpeq)
diff --git a/sysdeps/powerpc/powerpc64/power7/memcmp.S b/sysdeps/powerpc/powerpc64/power7/memcmp.S
index bc034a55bc..b541978b5f 100644
--- a/sysdeps/powerpc/powerpc64/power7/memcmp.S
+++ b/sysdeps/powerpc/powerpc64/power7/memcmp.S
@@ -1059,3 +1059,4 @@  L(duzeroLength):
 END (MEMCMP)
 libc_hidden_builtin_def (memcmp)
 weak_alias (memcmp, bcmp)
+weak_alias (memcmp, __memcmpeq)
diff --git a/sysdeps/powerpc/powerpc64/power8/memcmp.S b/sysdeps/powerpc/powerpc64/power8/memcmp.S
index b676b09a9b..d4f84a5b6f 100644
--- a/sysdeps/powerpc/powerpc64/power8/memcmp.S
+++ b/sysdeps/powerpc/powerpc64/power8/memcmp.S
@@ -1442,3 +1442,4 @@  L(duzeroLength):
 END (MEMCMP)
 libc_hidden_builtin_def (memcmp)
 weak_alias (memcmp, bcmp)
+weak_alias (memcmp, __memcmpeq)
diff --git a/sysdeps/s390/memcmp-z900.S b/sysdeps/s390/memcmp-z900.S
index 995d52e47d..0942d32814 100644
--- a/sysdeps/s390/memcmp-z900.S
+++ b/sysdeps/s390/memcmp-z900.S
@@ -164,6 +164,7 @@  END(MEMCMP_Z196)
    Otherwise see sysdeps/s390/memcmp.c.  */
 strong_alias (MEMCMP_DEFAULT, memcmp)
 weak_alias (memcmp, bcmp)
+weak_alias (memcmp, __memcmpeq)
 #endif
 
 #if defined SHARED && IS_IN (libc)
diff --git a/sysdeps/s390/memcmp.c b/sysdeps/s390/memcmp.c
index 0b4e9da717..475fc45d3a 100644
--- a/sysdeps/s390/memcmp.c
+++ b/sysdeps/s390/memcmp.c
@@ -46,4 +46,5 @@  s390_libc_ifunc_expr (__redirect_memcmp, memcmp,
 		      })
 		      )
 weak_alias (memcmp, bcmp);
+weak_alias (memcmp, __memcmpeq)
 #endif
diff --git a/sysdeps/sparc/sparc64/memcmp.S b/sysdeps/sparc/sparc64/memcmp.S
index d8d9ff9b24..edcc19915a 100644
--- a/sysdeps/sparc/sparc64/memcmp.S
+++ b/sysdeps/sparc/sparc64/memcmp.S
@@ -137,4 +137,6 @@  END(memcmp)
 
 #undef bcmp
 weak_alias (memcmp, bcmp)
+#undef __memcmpeq
+weak_alias (memcmp, __memcmpeq)
 libc_hidden_builtin_def (memcmp)
diff --git a/sysdeps/unix/sysv/linux/aarch64/libc.abilist b/sysdeps/unix/sysv/linux/aarch64/libc.abilist
index 21a2e50a88..f227ae6cee 100644
--- a/sysdeps/unix/sysv/linux/aarch64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/aarch64/libc.abilist
@@ -2612,3 +2612,4 @@  GLIBC_2.34 tss_create F
 GLIBC_2.34 tss_delete F
 GLIBC_2.34 tss_get F
 GLIBC_2.34 tss_set F
+GLIBC_2.35 __memcmpeq F
diff --git a/sysdeps/unix/sysv/linux/alpha/libc.abilist b/sysdeps/unix/sysv/linux/alpha/libc.abilist
index a201fd69ba..0ccc3fc73e 100644
--- a/sysdeps/unix/sysv/linux/alpha/libc.abilist
+++ b/sysdeps/unix/sysv/linux/alpha/libc.abilist
@@ -2709,6 +2709,7 @@  GLIBC_2.34 tss_create F
 GLIBC_2.34 tss_delete F
 GLIBC_2.34 tss_get F
 GLIBC_2.34 tss_set F
+GLIBC_2.35 __memcmpeq F
 GLIBC_2.4 _IO_fprintf F
 GLIBC_2.4 _IO_printf F
 GLIBC_2.4 _IO_sprintf F
diff --git a/sysdeps/unix/sysv/linux/arc/libc.abilist b/sysdeps/unix/sysv/linux/arc/libc.abilist
index 2611436937..fd80704787 100644
--- a/sysdeps/unix/sysv/linux/arc/libc.abilist
+++ b/sysdeps/unix/sysv/linux/arc/libc.abilist
@@ -2373,3 +2373,4 @@  GLIBC_2.34 tss_create F
 GLIBC_2.34 tss_delete F
 GLIBC_2.34 tss_get F
 GLIBC_2.34 tss_set F
+GLIBC_2.35 __memcmpeq F
diff --git a/sysdeps/unix/sysv/linux/arm/be/libc.abilist b/sysdeps/unix/sysv/linux/arm/be/libc.abilist
index a426241965..2ae6c58b8a 100644
--- a/sysdeps/unix/sysv/linux/arm/be/libc.abilist
+++ b/sysdeps/unix/sysv/linux/arm/be/libc.abilist
@@ -491,6 +491,7 @@  GLIBC_2.34 tss_create F
 GLIBC_2.34 tss_delete F
 GLIBC_2.34 tss_get F
 GLIBC_2.34 tss_set F
+GLIBC_2.35 __memcmpeq F
 GLIBC_2.4 _Exit F
 GLIBC_2.4 _IO_2_1_stderr_ D 0xa0
 GLIBC_2.4 _IO_2_1_stdin_ D 0xa0
diff --git a/sysdeps/unix/sysv/linux/arm/le/libc.abilist b/sysdeps/unix/sysv/linux/arm/le/libc.abilist
index 02f80418cc..fcfd1e8594 100644
--- a/sysdeps/unix/sysv/linux/arm/le/libc.abilist
+++ b/sysdeps/unix/sysv/linux/arm/le/libc.abilist
@@ -488,6 +488,7 @@  GLIBC_2.34 tss_create F
 GLIBC_2.34 tss_delete F
 GLIBC_2.34 tss_get F
 GLIBC_2.34 tss_set F
+GLIBC_2.35 __memcmpeq F
 GLIBC_2.4 _Exit F
 GLIBC_2.4 _IO_2_1_stderr_ D 0xa0
 GLIBC_2.4 _IO_2_1_stdin_ D 0xa0
diff --git a/sysdeps/unix/sysv/linux/csky/libc.abilist b/sysdeps/unix/sysv/linux/csky/libc.abilist
index b7676eb372..ba034b8541 100644
--- a/sysdeps/unix/sysv/linux/csky/libc.abilist
+++ b/sysdeps/unix/sysv/linux/csky/libc.abilist
@@ -2647,3 +2647,4 @@  GLIBC_2.34 tss_create F
 GLIBC_2.34 tss_delete F
 GLIBC_2.34 tss_get F
 GLIBC_2.34 tss_set F
+GLIBC_2.35 __memcmpeq F
diff --git a/sysdeps/unix/sysv/linux/hppa/libc.abilist b/sysdeps/unix/sysv/linux/hppa/libc.abilist
index f6965c9d95..b7460bec8a 100644
--- a/sysdeps/unix/sysv/linux/hppa/libc.abilist
+++ b/sysdeps/unix/sysv/linux/hppa/libc.abilist
@@ -2596,6 +2596,7 @@  GLIBC_2.34 tss_create F
 GLIBC_2.34 tss_delete F
 GLIBC_2.34 tss_get F
 GLIBC_2.34 tss_set F
+GLIBC_2.35 __memcmpeq F
 GLIBC_2.4 __confstr_chk F
 GLIBC_2.4 __fgets_chk F
 GLIBC_2.4 __fgets_unlocked_chk F
diff --git a/sysdeps/unix/sysv/linux/i386/libc.abilist b/sysdeps/unix/sysv/linux/i386/libc.abilist
index 2e7603d9ed..a4dc341ded 100644
--- a/sysdeps/unix/sysv/linux/i386/libc.abilist
+++ b/sysdeps/unix/sysv/linux/i386/libc.abilist
@@ -2780,6 +2780,7 @@  GLIBC_2.34 tss_create F
 GLIBC_2.34 tss_delete F
 GLIBC_2.34 tss_get F
 GLIBC_2.34 tss_set F
+GLIBC_2.35 __memcmpeq F
 GLIBC_2.4 __confstr_chk F
 GLIBC_2.4 __fgets_chk F
 GLIBC_2.4 __fgets_unlocked_chk F
diff --git a/sysdeps/unix/sysv/linux/ia64/libc.abilist b/sysdeps/unix/sysv/linux/ia64/libc.abilist
index dd3a56d3fe..94b222dbc7 100644
--- a/sysdeps/unix/sysv/linux/ia64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/ia64/libc.abilist
@@ -2547,6 +2547,7 @@  GLIBC_2.34 tss_create F
 GLIBC_2.34 tss_delete F
 GLIBC_2.34 tss_get F
 GLIBC_2.34 tss_set F
+GLIBC_2.35 __memcmpeq F
 GLIBC_2.4 __confstr_chk F
 GLIBC_2.4 __fgets_chk F
 GLIBC_2.4 __fgets_unlocked_chk F
diff --git a/sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist b/sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist
index c1e0ea9c10..12fd3b6310 100644
--- a/sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist
+++ b/sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist
@@ -492,6 +492,7 @@  GLIBC_2.34 tss_create F
 GLIBC_2.34 tss_delete F
 GLIBC_2.34 tss_get F
 GLIBC_2.34 tss_set F
+GLIBC_2.35 __memcmpeq F
 GLIBC_2.4 _Exit F
 GLIBC_2.4 _IO_2_1_stderr_ D 0x98
 GLIBC_2.4 _IO_2_1_stdin_ D 0x98
diff --git a/sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist b/sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist
index 93161048ca..4d2296007a 100644
--- a/sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist
+++ b/sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist
@@ -2723,6 +2723,7 @@  GLIBC_2.34 tss_create F
 GLIBC_2.34 tss_delete F
 GLIBC_2.34 tss_get F
 GLIBC_2.34 tss_set F
+GLIBC_2.35 __memcmpeq F
 GLIBC_2.4 __confstr_chk F
 GLIBC_2.4 __fgets_chk F
 GLIBC_2.4 __fgets_unlocked_chk F
diff --git a/sysdeps/unix/sysv/linux/microblaze/be/libc.abilist b/sysdeps/unix/sysv/linux/microblaze/be/libc.abilist
index 0aaeec8a27..a223278a3d 100644
--- a/sysdeps/unix/sysv/linux/microblaze/be/libc.abilist
+++ b/sysdeps/unix/sysv/linux/microblaze/be/libc.abilist
@@ -2696,3 +2696,4 @@  GLIBC_2.34 tss_create F
 GLIBC_2.34 tss_delete F
 GLIBC_2.34 tss_get F
 GLIBC_2.34 tss_set F
+GLIBC_2.35 __memcmpeq F
diff --git a/sysdeps/unix/sysv/linux/microblaze/le/libc.abilist b/sysdeps/unix/sysv/linux/microblaze/le/libc.abilist
index bec5f456c9..780a4f5b0b 100644
--- a/sysdeps/unix/sysv/linux/microblaze/le/libc.abilist
+++ b/sysdeps/unix/sysv/linux/microblaze/le/libc.abilist
@@ -2693,3 +2693,4 @@  GLIBC_2.34 tss_create F
 GLIBC_2.34 tss_delete F
 GLIBC_2.34 tss_get F
 GLIBC_2.34 tss_set F
+GLIBC_2.35 __memcmpeq F
diff --git a/sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist b/sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist
index 97d2127f78..cd65136062 100644
--- a/sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist
+++ b/sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist
@@ -2688,6 +2688,7 @@  GLIBC_2.34 tss_create F
 GLIBC_2.34 tss_delete F
 GLIBC_2.34 tss_get F
 GLIBC_2.34 tss_set F
+GLIBC_2.35 __memcmpeq F
 GLIBC_2.4 __confstr_chk F
 GLIBC_2.4 __fgets_chk F
 GLIBC_2.4 __fgets_unlocked_chk F
diff --git a/sysdeps/unix/sysv/linux/mips/mips32/nofpu/libc.abilist b/sysdeps/unix/sysv/linux/mips/mips32/nofpu/libc.abilist
index acb0756c11..b5b9902db5 100644
--- a/sysdeps/unix/sysv/linux/mips/mips32/nofpu/libc.abilist
+++ b/sysdeps/unix/sysv/linux/mips/mips32/nofpu/libc.abilist
@@ -2686,6 +2686,7 @@  GLIBC_2.34 tss_create F
 GLIBC_2.34 tss_delete F
 GLIBC_2.34 tss_get F
 GLIBC_2.34 tss_set F
+GLIBC_2.35 __memcmpeq F
 GLIBC_2.4 __confstr_chk F
 GLIBC_2.4 __fgets_chk F
 GLIBC_2.4 __fgets_unlocked_chk F
diff --git a/sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist b/sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist
index ebc21dde1e..57593d5f94 100644
--- a/sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist
+++ b/sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist
@@ -2694,6 +2694,7 @@  GLIBC_2.34 tss_create F
 GLIBC_2.34 tss_delete F
 GLIBC_2.34 tss_get F
 GLIBC_2.34 tss_set F
+GLIBC_2.35 __memcmpeq F
 GLIBC_2.4 __confstr_chk F
 GLIBC_2.4 __fgets_chk F
 GLIBC_2.4 __fgets_unlocked_chk F
diff --git a/sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist b/sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist
index c68f7e3c6c..e944d76bed 100644
--- a/sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist
@@ -2598,6 +2598,7 @@  GLIBC_2.34 tss_create F
 GLIBC_2.34 tss_delete F
 GLIBC_2.34 tss_get F
 GLIBC_2.34 tss_set F
+GLIBC_2.35 __memcmpeq F
 GLIBC_2.4 __confstr_chk F
 GLIBC_2.4 __fgets_chk F
 GLIBC_2.4 __fgets_unlocked_chk F
diff --git a/sysdeps/unix/sysv/linux/nios2/libc.abilist b/sysdeps/unix/sysv/linux/nios2/libc.abilist
index e5b6834f14..8af5a3a90d 100644
--- a/sysdeps/unix/sysv/linux/nios2/libc.abilist
+++ b/sysdeps/unix/sysv/linux/nios2/libc.abilist
@@ -2735,3 +2735,4 @@  GLIBC_2.34 tss_create F
 GLIBC_2.34 tss_delete F
 GLIBC_2.34 tss_get F
 GLIBC_2.34 tss_set F
+GLIBC_2.35 __memcmpeq F
diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist b/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist
index 132707c8ad..3a0213b39f 100644
--- a/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist
@@ -2750,6 +2750,7 @@  GLIBC_2.34 tss_create F
 GLIBC_2.34 tss_delete F
 GLIBC_2.34 tss_get F
 GLIBC_2.34 tss_set F
+GLIBC_2.35 __memcmpeq F
 GLIBC_2.4 _IO_fprintf F
 GLIBC_2.4 _IO_printf F
 GLIBC_2.4 _IO_sprintf F
diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist b/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist
index 0af2be31a0..f57df0234b 100644
--- a/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist
@@ -2783,6 +2783,7 @@  GLIBC_2.34 tss_create F
 GLIBC_2.34 tss_delete F
 GLIBC_2.34 tss_get F
 GLIBC_2.34 tss_set F
+GLIBC_2.35 __memcmpeq F
 GLIBC_2.4 _IO_fprintf F
 GLIBC_2.4 _IO_printf F
 GLIBC_2.4 _IO_sprintf F
diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc64/be/libc.abilist b/sysdeps/unix/sysv/linux/powerpc/powerpc64/be/libc.abilist
index cf864632d0..259a0cfc51 100644
--- a/sysdeps/unix/sysv/linux/powerpc/powerpc64/be/libc.abilist
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc64/be/libc.abilist
@@ -2506,6 +2506,7 @@  GLIBC_2.34 tss_create F
 GLIBC_2.34 tss_delete F
 GLIBC_2.34 tss_get F
 GLIBC_2.34 tss_set F
+GLIBC_2.35 __memcmpeq F
 GLIBC_2.4 _IO_fprintf F
 GLIBC_2.4 _IO_printf F
 GLIBC_2.4 _IO_sprintf F
diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc64/le/libc.abilist b/sysdeps/unix/sysv/linux/powerpc/powerpc64/le/libc.abilist
index d566d675d0..126541daf1 100644
--- a/sysdeps/unix/sysv/linux/powerpc/powerpc64/le/libc.abilist
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc64/le/libc.abilist
@@ -2808,3 +2808,4 @@  GLIBC_2.34 tss_create F
 GLIBC_2.34 tss_delete F
 GLIBC_2.34 tss_get F
 GLIBC_2.34 tss_set F
+GLIBC_2.35 __memcmpeq F
diff --git a/sysdeps/unix/sysv/linux/riscv/rv32/libc.abilist b/sysdeps/unix/sysv/linux/riscv/rv32/libc.abilist
index c9a7eacb32..05df4d13d2 100644
--- a/sysdeps/unix/sysv/linux/riscv/rv32/libc.abilist
+++ b/sysdeps/unix/sysv/linux/riscv/rv32/libc.abilist
@@ -2375,3 +2375,4 @@  GLIBC_2.34 tss_create F
 GLIBC_2.34 tss_delete F
 GLIBC_2.34 tss_get F
 GLIBC_2.34 tss_set F
+GLIBC_2.35 __memcmpeq F
diff --git a/sysdeps/unix/sysv/linux/riscv/rv64/libc.abilist b/sysdeps/unix/sysv/linux/riscv/rv64/libc.abilist
index 8299131cb2..8e349cbff8 100644
--- a/sysdeps/unix/sysv/linux/riscv/rv64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/riscv/rv64/libc.abilist
@@ -2575,3 +2575,4 @@  GLIBC_2.34 tss_create F
 GLIBC_2.34 tss_delete F
 GLIBC_2.34 tss_get F
 GLIBC_2.34 tss_set F
+GLIBC_2.35 __memcmpeq F
diff --git a/sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist b/sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist
index c3fe78f77f..e9de402766 100644
--- a/sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist
+++ b/sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist
@@ -2748,6 +2748,7 @@  GLIBC_2.34 tss_create F
 GLIBC_2.34 tss_delete F
 GLIBC_2.34 tss_get F
 GLIBC_2.34 tss_set F
+GLIBC_2.35 __memcmpeq F
 GLIBC_2.4 _IO_fprintf F
 GLIBC_2.4 _IO_printf F
 GLIBC_2.4 _IO_sprintf F
diff --git a/sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist b/sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist
index 83e542aa8c..1a010c745d 100644
--- a/sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist
@@ -2543,6 +2543,7 @@  GLIBC_2.34 tss_create F
 GLIBC_2.34 tss_delete F
 GLIBC_2.34 tss_get F
 GLIBC_2.34 tss_set F
+GLIBC_2.35 __memcmpeq F
 GLIBC_2.4 _IO_fprintf F
 GLIBC_2.4 _IO_printf F
 GLIBC_2.4 _IO_sprintf F
diff --git a/sysdeps/unix/sysv/linux/sh/be/libc.abilist b/sysdeps/unix/sysv/linux/sh/be/libc.abilist
index dc502f6833..22ce530975 100644
--- a/sysdeps/unix/sysv/linux/sh/be/libc.abilist
+++ b/sysdeps/unix/sysv/linux/sh/be/libc.abilist
@@ -2603,6 +2603,7 @@  GLIBC_2.34 tss_create F
 GLIBC_2.34 tss_delete F
 GLIBC_2.34 tss_get F
 GLIBC_2.34 tss_set F
+GLIBC_2.35 __memcmpeq F
 GLIBC_2.4 __confstr_chk F
 GLIBC_2.4 __fgets_chk F
 GLIBC_2.4 __fgets_unlocked_chk F
diff --git a/sysdeps/unix/sysv/linux/sh/le/libc.abilist b/sysdeps/unix/sysv/linux/sh/le/libc.abilist
index cba1abb556..960df07b83 100644
--- a/sysdeps/unix/sysv/linux/sh/le/libc.abilist
+++ b/sysdeps/unix/sysv/linux/sh/le/libc.abilist
@@ -2600,6 +2600,7 @@  GLIBC_2.34 tss_create F
 GLIBC_2.34 tss_delete F
 GLIBC_2.34 tss_get F
 GLIBC_2.34 tss_set F
+GLIBC_2.35 __memcmpeq F
 GLIBC_2.4 __confstr_chk F
 GLIBC_2.4 __fgets_chk F
 GLIBC_2.4 __fgets_unlocked_chk F
diff --git a/sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist b/sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist
index d4a516fb47..eedb376f3d 100644
--- a/sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist
+++ b/sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist
@@ -2743,6 +2743,7 @@  GLIBC_2.34 tss_create F
 GLIBC_2.34 tss_delete F
 GLIBC_2.34 tss_get F
 GLIBC_2.34 tss_set F
+GLIBC_2.35 __memcmpeq F
 GLIBC_2.4 _IO_fprintf F
 GLIBC_2.4 _IO_printf F
 GLIBC_2.4 _IO_sprintf F
diff --git a/sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist b/sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist
index 6268875ba3..86e0c92bef 100644
--- a/sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist
@@ -2570,6 +2570,7 @@  GLIBC_2.34 tss_create F
 GLIBC_2.34 tss_delete F
 GLIBC_2.34 tss_get F
 GLIBC_2.34 tss_set F
+GLIBC_2.35 __memcmpeq F
 GLIBC_2.4 __confstr_chk F
 GLIBC_2.4 __fgets_chk F
 GLIBC_2.4 __fgets_unlocked_chk F
diff --git a/sysdeps/unix/sysv/linux/x86_64/64/libc.abilist b/sysdeps/unix/sysv/linux/x86_64/64/libc.abilist
index 095e914b73..5e59d90623 100644
--- a/sysdeps/unix/sysv/linux/x86_64/64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/x86_64/64/libc.abilist
@@ -2521,6 +2521,7 @@  GLIBC_2.34 tss_create F
 GLIBC_2.34 tss_delete F
 GLIBC_2.34 tss_get F
 GLIBC_2.34 tss_set F
+GLIBC_2.35 __memcmpeq F
 GLIBC_2.4 __confstr_chk F
 GLIBC_2.4 __fgets_chk F
 GLIBC_2.4 __fgets_unlocked_chk F
diff --git a/sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist b/sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist
index dd910f7fe9..94412dc134 100644
--- a/sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist
+++ b/sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist
@@ -2627,3 +2627,4 @@  GLIBC_2.34 tss_create F
 GLIBC_2.34 tss_delete F
 GLIBC_2.34 tss_get F
 GLIBC_2.34 tss_set F
+GLIBC_2.35 __memcmpeq F
diff --git a/sysdeps/x86_64/memcmp.S b/sysdeps/x86_64/memcmp.S
index 870e15c5a0..f41ae48006 100644
--- a/sysdeps/x86_64/memcmp.S
+++ b/sysdeps/x86_64/memcmp.S
@@ -358,4 +358,6 @@  END(memcmp)
 
 #undef bcmp
 weak_alias (memcmp, bcmp)
+#undef __memcmpeq
+weak_alias (memcmp, __memcmpeq)
 libc_hidden_builtin_def (memcmp)
diff --git a/sysdeps/x86_64/multiarch/memcmp.c b/sysdeps/x86_64/multiarch/memcmp.c
index fe725f3563..fe125e0904 100644
--- a/sysdeps/x86_64/multiarch/memcmp.c
+++ b/sysdeps/x86_64/multiarch/memcmp.c
@@ -29,6 +29,8 @@ 
 libc_ifunc_redirected (__redirect_memcmp, memcmp, IFUNC_SELECTOR ());
 # undef bcmp
 weak_alias (memcmp, bcmp)
+# undef __memcmpeq
+weak_alias (memcmp, __memcmpeq)
 
 # ifdef SHARED
 __hidden_ver1 (memcmp, __GI_memcmp, __redirect_memcmp)