[v1] String: Add support for __memcmpeq() ABI on all targets

Message ID 20210927203827.2852935-1-goldstein.w.n@gmail.com
State Superseded
Headers
Series [v1] String: Add support for __memcmpeq() ABI on all targets |

Checks

Context Check Description
dj/TryBot-32bit success Build for i686
dj/TryBot-apply_patch success Patch applied to master at the time it was sent

Commit Message

Noah Goldstein Sept. 27, 2021, 8:38 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.
---
Note: I did not test with build-many-glibcs.py. So far I have not been
able to get it working. The only ABI I tested was x86_64-linux-gnu.
    
Essentially what I did was go through all reference to bcmp() and add
the corresponding logic for __memcmpeq(). If bcmp() was missing for
any arch then this patch will have missed an alias.

There are two places I did not mirror the existing logic for bcmp()
I didn't include anything in 'conform/data/strings.h-data'. I also
defined __memcmpeq() in 'string/string.h' as opposed to
'string/strings.h'.

One thing I am concerned about is some arch having an optimized
version of memcmp() but no alias for __memcmpeq(). If this happens
replacing the optimized memcmp() will the fallback __memcmpeq() will
likely be an anti-optimization.

This is a list of all memcmp implementations:

'$' means it contains an alias to __memcmpeq()
'*' means it includes a file with an alias
'^' means its just making declarations
'%' means its an implementation without an alias

$ sysdeps/sparc/sparc64/memcmp.S
$ sysdeps/sparc/sparc32/sparcv9/memcmp.S
$ sysdeps/s390/memcmp-z900.S
$ sysdeps/s390/memcmp.c
$ sysdeps/powerpc/powerpc32/405/memcmp.S
$ sysdeps/powerpc/powerpc32/power4/memcmp.S
* sysdeps/powerpc/powerpc32/power4/multiarch/memcmp-power7.S
* sysdeps/powerpc/powerpc32/power4/multiarch/memcmp-ppc32.S
^ sysdeps/powerpc/powerpc32/power4/multiarch/memcmp.c
* sysdeps/powerpc/powerpc32/power4/multiarch/rtld-memcmp.S
$ sysdeps/powerpc/powerpc32/power7/memcmp.S
$ sysdeps/powerpc/powerpc64/power8/memcmp.S
$ sysdeps/powerpc/powerpc64/power4/memcmp.S
* sysdeps/powerpc/powerpc64/multiarch/memcmp-power7.S 
* sysdeps/powerpc/powerpc64/multiarch/memcmp-power8.S
* sysdeps/powerpc/powerpc64/multiarch/memcmp-power4.S
* sysdeps/powerpc/powerpc64/multiarch/memcmp-power10.S
^ sysdeps/powerpc/powerpc64/multiarch/memcmp.c
^ sysdeps/powerpc/powerpc64/multiarch/memcmp-ppc64.c
$ sysdeps/powerpc/powerpc64/le/power10/memcmp.S
$ sysdeps/powerpc/powerpc64/power7/memcmp.S
$ sysdeps/aarch64/memcmp.S
$ sysdeps/ia64/memcmp.S
$ sysdeps/i386/i686/memcmp.S
% sysdeps/i386/i686/multiarch/memcmp-sse4.S
% sysdeps/i386/i686/multiarch/memcmp-ssse3.S
% sysdeps/i386/i686/multiarch/memcmp-ia32.S
$ sysdeps/i386/i686/multiarch/memcmp.c
$ sysdeps/i386/memcmp.S
$ sysdeps/x86_64/memcmp.S
% sysdeps/x86_64/multiarch/memcmp-sse4.S
% sysdeps/x86_64/multiarch/memcmp-ssse3.S
% sysdeps/x86_64/multiarch/memcmp-avx2-movbe.S
% sysdeps/x86_64/multiarch/memcmp-sse2.S
% sysdeps/x86_64/multiarch/memcmp-avx2-movbe-rtm.S
% sysdeps/x86_64/multiarch/memcmp-evex-movbe.S
$ sysdeps/x86_64/multiarch/memcmp.c
$ sysdeps/csky/abiv2/memcmp.S
$ string/memcmp.c

As far as I can tell everything is covered. I tested on x86_64 that
the '%' implements will redirect bcmp() to the correct ifunc
selection.

 string/Versions                                  |  3 +++
 string/memcmp.c                                  |  2 ++
 string/string.h                                  | 13 +++++++++++++
 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, 91 insertions(+)
  

Comments

Joseph Myers Sept. 27, 2021, 8:43 p.m. UTC | #1
On Mon, 27 Sep 2021, Noah Goldstein via Libc-alpha wrote:

> +/* Compare N bytes of S1 and S2. Return zero if S1 and S2 are equals. Return
> +   some non-zero value otherwise.
> +
> +   Essentially 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.
> +
> +   Used by compilers when memcmp() return is only used for its bolean
> +   value.  */

GNU standards say not to use () after a function name to indicate that 
it's a function, only when you actually want a function call with no 
arguments.  Also, two spaces after '.' at end of sentence.

> +GLIBC_3.5 __memcmpeq F

That's the wrong version.

> +GLIBC_3.5 __memcmpeq F
> \ No newline at end of file

Likewise, and these files should all end with a newline.
  
Noah Goldstein Sept. 27, 2021, 9:06 p.m. UTC | #2
On Mon, Sep 27, 2021 at 3:43 PM Joseph Myers <joseph@codesourcery.com> wrote:
>
> On Mon, 27 Sep 2021, Noah Goldstein via Libc-alpha wrote:
>
> > +/* Compare N bytes of S1 and S2. Return zero if S1 and S2 are equals. Return
> > +   some non-zero value otherwise.
> > +
> > +   Essentially 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.
> > +
> > +   Used by compilers when memcmp() return is only used for its bolean
> > +   value.  */
>
> GNU standards say not to use () after a function name to indicate that
> it's a function, only when you actually want a function call with no
> arguments.  Also, two spaces after '.' at end of sentence.

Fixed.

>
> > +GLIBC_3.5 __memcmpeq F
>
> That's the wrong version.
>
> > +GLIBC_3.5 __memcmpeq F
> > \ No newline at end of file
>
> Likewise, and these files should all end with a newline.

Fixed.

>
> --
> Joseph S. Myers
> joseph@codesourcery.com
  
Noah Goldstein Sept. 28, 2021, 4:57 p.m. UTC | #3
On Mon, Sep 27, 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.
> ---
> Note: I did not test with build-many-glibcs.py. So far I have not been
> able to get it working. The only ABI I tested was x86_64-linux-gnu.

Started build-many-glibcs.py tests. Last night all builds passed
From:
compilers-aarch64-linux-gnu check-host-libraries
To:
compilers-mips64-linux-gnu-soft glibc mips64-linux-gnu-n32-soft build

As well as x86_64 and x86_32.

>
> Essentially what I did was go through all reference to bcmp() and add
> the corresponding logic for __memcmpeq(). If bcmp() was missing for
> any arch then this patch will have missed an alias.
>
> There are two places I did not mirror the existing logic for bcmp()
> I didn't include anything in 'conform/data/strings.h-data'. I also
> defined __memcmpeq() in 'string/string.h' as opposed to
> 'string/strings.h'.
>
> One thing I am concerned about is some arch having an optimized
> version of memcmp() but no alias for __memcmpeq(). If this happens
> replacing the optimized memcmp() will the fallback __memcmpeq() will
> likely be an anti-optimization.
>
> This is a list of all memcmp implementations:
>
> '$' means it contains an alias to __memcmpeq()
> '*' means it includes a file with an alias
> '^' means its just making declarations
> '%' means its an implementation without an alias
>
> $ sysdeps/sparc/sparc64/memcmp.S
> $ sysdeps/sparc/sparc32/sparcv9/memcmp.S
> $ sysdeps/s390/memcmp-z900.S
> $ sysdeps/s390/memcmp.c
> $ sysdeps/powerpc/powerpc32/405/memcmp.S
> $ sysdeps/powerpc/powerpc32/power4/memcmp.S
> * sysdeps/powerpc/powerpc32/power4/multiarch/memcmp-power7.S
> * sysdeps/powerpc/powerpc32/power4/multiarch/memcmp-ppc32.S
> ^ sysdeps/powerpc/powerpc32/power4/multiarch/memcmp.c
> * sysdeps/powerpc/powerpc32/power4/multiarch/rtld-memcmp.S
> $ sysdeps/powerpc/powerpc32/power7/memcmp.S
> $ sysdeps/powerpc/powerpc64/power8/memcmp.S
> $ sysdeps/powerpc/powerpc64/power4/memcmp.S
> * sysdeps/powerpc/powerpc64/multiarch/memcmp-power7.S
> * sysdeps/powerpc/powerpc64/multiarch/memcmp-power8.S
> * sysdeps/powerpc/powerpc64/multiarch/memcmp-power4.S
> * sysdeps/powerpc/powerpc64/multiarch/memcmp-power10.S
> ^ sysdeps/powerpc/powerpc64/multiarch/memcmp.c
> ^ sysdeps/powerpc/powerpc64/multiarch/memcmp-ppc64.c
> $ sysdeps/powerpc/powerpc64/le/power10/memcmp.S
> $ sysdeps/powerpc/powerpc64/power7/memcmp.S
> $ sysdeps/aarch64/memcmp.S
> $ sysdeps/ia64/memcmp.S
> $ sysdeps/i386/i686/memcmp.S
> % sysdeps/i386/i686/multiarch/memcmp-sse4.S
> % sysdeps/i386/i686/multiarch/memcmp-ssse3.S
> % sysdeps/i386/i686/multiarch/memcmp-ia32.S
> $ sysdeps/i386/i686/multiarch/memcmp.c
> $ sysdeps/i386/memcmp.S
> $ sysdeps/x86_64/memcmp.S
> % sysdeps/x86_64/multiarch/memcmp-sse4.S
> % sysdeps/x86_64/multiarch/memcmp-ssse3.S
> % sysdeps/x86_64/multiarch/memcmp-avx2-movbe.S
> % sysdeps/x86_64/multiarch/memcmp-sse2.S
> % sysdeps/x86_64/multiarch/memcmp-avx2-movbe-rtm.S
> % sysdeps/x86_64/multiarch/memcmp-evex-movbe.S
> $ sysdeps/x86_64/multiarch/memcmp.c
> $ sysdeps/csky/abiv2/memcmp.S
> $ string/memcmp.c
>
> As far as I can tell everything is covered. I tested on x86_64 that
> the '%' implements will redirect bcmp() to the correct ifunc
> selection.
>
>  string/Versions                                  |  3 +++
>  string/memcmp.c                                  |  2 ++
>  string/string.h                                  | 13 +++++++++++++
>  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, 91 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..550b7bb69b 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 04e1b7067d..e953599525 100644
> --- a/string/string.h
> +++ b/string/string.h
> @@ -64,6 +64,19 @@ 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 equals. Return
> +   some non-zero value otherwise.
> +
> +   Essentially 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.
> +
> +   Used by compilers when memcmp() return is only used for its bolean
> +   value.  */
> +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..7d8e1b7c1e 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..dcd1fadd88 100644
> --- a/sysdeps/mach/hurd/i386/libc.abilist
> +++ b/sysdeps/mach/hurd/i386/libc.abilist
> @@ -2409,6 +2409,7 @@ GLIBC_2.9 ns_name_skip F
>  GLIBC_2.9 ns_name_uncompress F
>  GLIBC_2.9 ns_name_unpack F
>  GLIBC_2.9 pipe2 F
> +GLIBC_3.5 __memcmpeq F
>  HURD_CTHREADS_0.3 __cthread_getspecific F
>  HURD_CTHREADS_0.3 __cthread_keycreate F
>  HURD_CTHREADS_0.3 __cthread_setspecific 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..8f49b255dd 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_3.5 __memcmpeq F
> \ No newline at end of file
> diff --git a/sysdeps/unix/sysv/linux/alpha/libc.abilist b/sysdeps/unix/sysv/linux/alpha/libc.abilist
> index a201fd69ba..b655fab937 100644
> --- a/sysdeps/unix/sysv/linux/alpha/libc.abilist
> +++ b/sysdeps/unix/sysv/linux/alpha/libc.abilist
> @@ -3037,3 +3037,4 @@ GLIBC_2.9 ns_name_skip F
>  GLIBC_2.9 ns_name_uncompress F
>  GLIBC_2.9 ns_name_unpack F
>  GLIBC_2.9 pipe2 F
> +GLIBC_3.5 __memcmpeq F
> \ No newline at end of file
> diff --git a/sysdeps/unix/sysv/linux/arc/libc.abilist b/sysdeps/unix/sysv/linux/arc/libc.abilist
> index 2611436937..9090fec640 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_3.5 __memcmpeq F
> \ No newline at end of file
> diff --git a/sysdeps/unix/sysv/linux/arm/be/libc.abilist b/sysdeps/unix/sysv/linux/arm/be/libc.abilist
> index a426241965..3e532f3a6e 100644
> --- a/sysdeps/unix/sysv/linux/arm/be/libc.abilist
> +++ b/sysdeps/unix/sysv/linux/arm/be/libc.abilist
> @@ -2736,3 +2736,4 @@ GLIBC_2.9 ns_name_skip F
>  GLIBC_2.9 ns_name_uncompress F
>  GLIBC_2.9 ns_name_unpack F
>  GLIBC_2.9 pipe2 F
> +GLIBC_3.5 __memcmpeq F
> \ No newline at end of file
> diff --git a/sysdeps/unix/sysv/linux/arm/le/libc.abilist b/sysdeps/unix/sysv/linux/arm/le/libc.abilist
> index 02f80418cc..2376520077 100644
> --- a/sysdeps/unix/sysv/linux/arm/le/libc.abilist
> +++ b/sysdeps/unix/sysv/linux/arm/le/libc.abilist
> @@ -2733,3 +2733,4 @@ GLIBC_2.9 ns_name_skip F
>  GLIBC_2.9 ns_name_uncompress F
>  GLIBC_2.9 ns_name_unpack F
>  GLIBC_2.9 pipe2 F
> +GLIBC_3.5 __memcmpeq F
> \ No newline at end of file
> diff --git a/sysdeps/unix/sysv/linux/csky/libc.abilist b/sysdeps/unix/sysv/linux/csky/libc.abilist
> index b7676eb372..70cd0ff05e 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_3.5 __memcmpeq F
> \ No newline at end of file
> diff --git a/sysdeps/unix/sysv/linux/hppa/libc.abilist b/sysdeps/unix/sysv/linux/hppa/libc.abilist
> index f6965c9d95..7056d3e4d6 100644
> --- a/sysdeps/unix/sysv/linux/hppa/libc.abilist
> +++ b/sysdeps/unix/sysv/linux/hppa/libc.abilist
> @@ -2755,3 +2755,4 @@ GLIBC_2.9 ns_name_skip F
>  GLIBC_2.9 ns_name_uncompress F
>  GLIBC_2.9 ns_name_unpack F
>  GLIBC_2.9 pipe2 F
> +GLIBC_3.5 __memcmpeq F
> \ No newline at end of file
> diff --git a/sysdeps/unix/sysv/linux/i386/libc.abilist b/sysdeps/unix/sysv/linux/i386/libc.abilist
> index 2e7603d9ed..8ffd4c2832 100644
> --- a/sysdeps/unix/sysv/linux/i386/libc.abilist
> +++ b/sysdeps/unix/sysv/linux/i386/libc.abilist
> @@ -2939,3 +2939,4 @@ GLIBC_2.9 ns_name_skip F
>  GLIBC_2.9 ns_name_uncompress F
>  GLIBC_2.9 ns_name_unpack F
>  GLIBC_2.9 pipe2 F
> +GLIBC_3.5 __memcmpeq F
> \ No newline at end of file
> diff --git a/sysdeps/unix/sysv/linux/ia64/libc.abilist b/sysdeps/unix/sysv/linux/ia64/libc.abilist
> index dd3a56d3fe..f8c405a3c1 100644
> --- a/sysdeps/unix/sysv/linux/ia64/libc.abilist
> +++ b/sysdeps/unix/sysv/linux/ia64/libc.abilist
> @@ -2706,3 +2706,4 @@ GLIBC_2.9 ns_name_skip F
>  GLIBC_2.9 ns_name_uncompress F
>  GLIBC_2.9 ns_name_unpack F
>  GLIBC_2.9 pipe2 F
> +GLIBC_3.5 __memcmpeq F
> \ No newline at end of file
> diff --git a/sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist b/sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist
> index c1e0ea9c10..c8b7557d26 100644
> --- a/sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist
> +++ b/sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist
> @@ -2715,3 +2715,4 @@ GLIBC_2.9 ns_name_skip F
>  GLIBC_2.9 ns_name_uncompress F
>  GLIBC_2.9 ns_name_unpack F
>  GLIBC_2.9 pipe2 F
> +GLIBC_3.5 __memcmpeq F
> \ No newline at end of file
> diff --git a/sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist b/sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist
> index 93161048ca..94f983248b 100644
> --- a/sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist
> +++ b/sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist
> @@ -2882,3 +2882,4 @@ GLIBC_2.9 ns_name_skip F
>  GLIBC_2.9 ns_name_uncompress F
>  GLIBC_2.9 ns_name_unpack F
>  GLIBC_2.9 pipe2 F
> +GLIBC_3.5 __memcmpeq F
> \ No newline at end of file
> diff --git a/sysdeps/unix/sysv/linux/microblaze/be/libc.abilist b/sysdeps/unix/sysv/linux/microblaze/be/libc.abilist
> index 0aaeec8a27..87f62551fe 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_3.5 __memcmpeq F
> \ No newline at end of file
> diff --git a/sysdeps/unix/sysv/linux/microblaze/le/libc.abilist b/sysdeps/unix/sysv/linux/microblaze/le/libc.abilist
> index bec5f456c9..a30ddf68ef 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_3.5 __memcmpeq F
> \ No newline at end of file
> diff --git a/sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist b/sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist
> index 97d2127f78..e54c14ccd1 100644
> --- a/sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist
> +++ b/sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist
> @@ -2843,3 +2843,4 @@ GLIBC_2.9 ns_name_skip F
>  GLIBC_2.9 ns_name_uncompress F
>  GLIBC_2.9 ns_name_unpack F
>  GLIBC_2.9 pipe2 F
> +GLIBC_3.5 __memcmpeq F
> \ No newline at end of file
> diff --git a/sysdeps/unix/sysv/linux/mips/mips32/nofpu/libc.abilist b/sysdeps/unix/sysv/linux/mips/mips32/nofpu/libc.abilist
> index acb0756c11..38aba84dc5 100644
> --- a/sysdeps/unix/sysv/linux/mips/mips32/nofpu/libc.abilist
> +++ b/sysdeps/unix/sysv/linux/mips/mips32/nofpu/libc.abilist
> @@ -2841,3 +2841,4 @@ GLIBC_2.9 ns_name_skip F
>  GLIBC_2.9 ns_name_uncompress F
>  GLIBC_2.9 ns_name_unpack F
>  GLIBC_2.9 pipe2 F
> +GLIBC_3.5 __memcmpeq F
> \ No newline at end of file
> diff --git a/sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist b/sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist
> index ebc21dde1e..a3605989e3 100644
> --- a/sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist
> +++ b/sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist
> @@ -2849,3 +2849,4 @@ GLIBC_2.9 ns_name_skip F
>  GLIBC_2.9 ns_name_uncompress F
>  GLIBC_2.9 ns_name_unpack F
>  GLIBC_2.9 pipe2 F
> +GLIBC_3.5 __memcmpeq F
> \ No newline at end of file
> diff --git a/sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist b/sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist
> index c68f7e3c6c..e6ffe45977 100644
> --- a/sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist
> +++ b/sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist
> @@ -2753,3 +2753,4 @@ GLIBC_2.9 ns_name_skip F
>  GLIBC_2.9 ns_name_uncompress F
>  GLIBC_2.9 ns_name_unpack F
>  GLIBC_2.9 pipe2 F
> +GLIBC_3.5 __memcmpeq F
> \ No newline at end of file
> diff --git a/sysdeps/unix/sysv/linux/nios2/libc.abilist b/sysdeps/unix/sysv/linux/nios2/libc.abilist
> index e5b6834f14..16776a5d25 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_3.5 __memcmpeq F
> \ No newline at end of file
> diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist b/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist
> index 132707c8ad..8dd99682a9 100644
> --- a/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist
> +++ b/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist
> @@ -3080,3 +3080,4 @@ GLIBC_2.9 ns_name_skip F
>  GLIBC_2.9 ns_name_uncompress F
>  GLIBC_2.9 ns_name_unpack F
>  GLIBC_2.9 pipe2 F
> +GLIBC_3.5 __memcmpeq F
> \ No newline at end of file
> diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist b/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist
> index 0af2be31a0..306c194aca 100644
> --- a/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist
> +++ b/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist
> @@ -3125,3 +3125,4 @@ GLIBC_2.9 ns_name_skip F
>  GLIBC_2.9 ns_name_uncompress F
>  GLIBC_2.9 ns_name_unpack F
>  GLIBC_2.9 pipe2 F
> +GLIBC_3.5 __memcmpeq F
> \ No newline at end of file
> diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc64/be/libc.abilist b/sysdeps/unix/sysv/linux/powerpc/powerpc64/be/libc.abilist
> index cf864632d0..a8e24f6aae 100644
> --- a/sysdeps/unix/sysv/linux/powerpc/powerpc64/be/libc.abilist
> +++ b/sysdeps/unix/sysv/linux/powerpc/powerpc64/be/libc.abilist
> @@ -2836,3 +2836,4 @@ GLIBC_2.9 ns_name_skip F
>  GLIBC_2.9 ns_name_uncompress F
>  GLIBC_2.9 ns_name_unpack F
>  GLIBC_2.9 pipe2 F
> +GLIBC_3.5 __memcmpeq F
> \ No newline at end of file
> diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc64/le/libc.abilist b/sysdeps/unix/sysv/linux/powerpc/powerpc64/le/libc.abilist
> index d566d675d0..f47d906947 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_3.5 __memcmpeq F
> \ No newline at end of file
> diff --git a/sysdeps/unix/sysv/linux/riscv/rv32/libc.abilist b/sysdeps/unix/sysv/linux/riscv/rv32/libc.abilist
> index c9a7eacb32..87b8554999 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_3.5 __memcmpeq F
> \ No newline at end of file
> diff --git a/sysdeps/unix/sysv/linux/riscv/rv64/libc.abilist b/sysdeps/unix/sysv/linux/riscv/rv64/libc.abilist
> index 8299131cb2..65147c4596 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_3.5 __memcmpeq F
> \ No newline at end of file
> diff --git a/sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist b/sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist
> index c3fe78f77f..d71ddcb6a5 100644
> --- a/sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist
> +++ b/sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist
> @@ -3092,3 +3092,4 @@ GLIBC_2.9 pututline F
>  GLIBC_2.9 pututxline F
>  GLIBC_2.9 updwtmp F
>  GLIBC_2.9 updwtmpx F
> +GLIBC_3.5 __memcmpeq F
> \ No newline at end of file
> diff --git a/sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist b/sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist
> index 83e542aa8c..88ae19acae 100644
> --- a/sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist
> +++ b/sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist
> @@ -2871,3 +2871,4 @@ GLIBC_2.9 ns_name_skip F
>  GLIBC_2.9 ns_name_uncompress F
>  GLIBC_2.9 ns_name_unpack F
>  GLIBC_2.9 pipe2 F
> +GLIBC_3.5 __memcmpeq F
> \ No newline at end of file
> diff --git a/sysdeps/unix/sysv/linux/sh/be/libc.abilist b/sysdeps/unix/sysv/linux/sh/be/libc.abilist
> index dc502f6833..5609329d85 100644
> --- a/sysdeps/unix/sysv/linux/sh/be/libc.abilist
> +++ b/sysdeps/unix/sysv/linux/sh/be/libc.abilist
> @@ -2762,3 +2762,4 @@ GLIBC_2.9 ns_name_skip F
>  GLIBC_2.9 ns_name_uncompress F
>  GLIBC_2.9 ns_name_unpack F
>  GLIBC_2.9 pipe2 F
> +GLIBC_3.5 __memcmpeq F
> \ No newline at end of file
> diff --git a/sysdeps/unix/sysv/linux/sh/le/libc.abilist b/sysdeps/unix/sysv/linux/sh/le/libc.abilist
> index cba1abb556..f3ce30fcc5 100644
> --- a/sysdeps/unix/sysv/linux/sh/le/libc.abilist
> +++ b/sysdeps/unix/sysv/linux/sh/le/libc.abilist
> @@ -2759,3 +2759,4 @@ GLIBC_2.9 ns_name_skip F
>  GLIBC_2.9 ns_name_uncompress F
>  GLIBC_2.9 ns_name_unpack F
>  GLIBC_2.9 pipe2 F
> +GLIBC_3.5 __memcmpeq F
> \ No newline at end of file
> diff --git a/sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist b/sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist
> index d4a516fb47..8d67b75244 100644
> --- a/sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist
> +++ b/sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist
> @@ -3097,3 +3097,4 @@ GLIBC_2.9 ns_name_skip F
>  GLIBC_2.9 ns_name_uncompress F
>  GLIBC_2.9 ns_name_unpack F
>  GLIBC_2.9 pipe2 F
> +GLIBC_3.5 __memcmpeq F
> \ No newline at end of file
> diff --git a/sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist b/sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist
> index 6268875ba3..999e7c1f05 100644
> --- a/sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist
> +++ b/sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist
> @@ -2729,3 +2729,4 @@ GLIBC_2.9 ns_name_skip F
>  GLIBC_2.9 ns_name_uncompress F
>  GLIBC_2.9 ns_name_unpack F
>  GLIBC_2.9 pipe2 F
> +GLIBC_3.5 __memcmpeq F
> \ No newline at end of file
> diff --git a/sysdeps/unix/sysv/linux/x86_64/64/libc.abilist b/sysdeps/unix/sysv/linux/x86_64/64/libc.abilist
> index 095e914b73..c5be6ef43e 100644
> --- a/sysdeps/unix/sysv/linux/x86_64/64/libc.abilist
> +++ b/sysdeps/unix/sysv/linux/x86_64/64/libc.abilist
> @@ -2680,3 +2680,4 @@ GLIBC_2.9 ns_name_skip F
>  GLIBC_2.9 ns_name_uncompress F
>  GLIBC_2.9 ns_name_unpack F
>  GLIBC_2.9 pipe2 F
> +GLIBC_3.5 __memcmpeq F
> \ No newline at end of file
> diff --git a/sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist b/sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist
> index dd910f7fe9..cc16ae6335 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_3.5 __memcmpeq F
> \ No newline at end of file
> 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..9cc4750bbc 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
>
  

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..550b7bb69b 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 04e1b7067d..e953599525 100644
--- a/string/string.h
+++ b/string/string.h
@@ -64,6 +64,19 @@  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 equals. Return
+   some non-zero value otherwise.
+
+   Essentially 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.
+
+   Used by compilers when memcmp() return is only used for its bolean
+   value.  */
+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..7d8e1b7c1e 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..dcd1fadd88 100644
--- a/sysdeps/mach/hurd/i386/libc.abilist
+++ b/sysdeps/mach/hurd/i386/libc.abilist
@@ -2409,6 +2409,7 @@  GLIBC_2.9 ns_name_skip F
 GLIBC_2.9 ns_name_uncompress F
 GLIBC_2.9 ns_name_unpack F
 GLIBC_2.9 pipe2 F
+GLIBC_3.5 __memcmpeq F
 HURD_CTHREADS_0.3 __cthread_getspecific F
 HURD_CTHREADS_0.3 __cthread_keycreate F
 HURD_CTHREADS_0.3 __cthread_setspecific 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..8f49b255dd 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_3.5 __memcmpeq F
\ No newline at end of file
diff --git a/sysdeps/unix/sysv/linux/alpha/libc.abilist b/sysdeps/unix/sysv/linux/alpha/libc.abilist
index a201fd69ba..b655fab937 100644
--- a/sysdeps/unix/sysv/linux/alpha/libc.abilist
+++ b/sysdeps/unix/sysv/linux/alpha/libc.abilist
@@ -3037,3 +3037,4 @@  GLIBC_2.9 ns_name_skip F
 GLIBC_2.9 ns_name_uncompress F
 GLIBC_2.9 ns_name_unpack F
 GLIBC_2.9 pipe2 F
+GLIBC_3.5 __memcmpeq F
\ No newline at end of file
diff --git a/sysdeps/unix/sysv/linux/arc/libc.abilist b/sysdeps/unix/sysv/linux/arc/libc.abilist
index 2611436937..9090fec640 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_3.5 __memcmpeq F
\ No newline at end of file
diff --git a/sysdeps/unix/sysv/linux/arm/be/libc.abilist b/sysdeps/unix/sysv/linux/arm/be/libc.abilist
index a426241965..3e532f3a6e 100644
--- a/sysdeps/unix/sysv/linux/arm/be/libc.abilist
+++ b/sysdeps/unix/sysv/linux/arm/be/libc.abilist
@@ -2736,3 +2736,4 @@  GLIBC_2.9 ns_name_skip F
 GLIBC_2.9 ns_name_uncompress F
 GLIBC_2.9 ns_name_unpack F
 GLIBC_2.9 pipe2 F
+GLIBC_3.5 __memcmpeq F
\ No newline at end of file
diff --git a/sysdeps/unix/sysv/linux/arm/le/libc.abilist b/sysdeps/unix/sysv/linux/arm/le/libc.abilist
index 02f80418cc..2376520077 100644
--- a/sysdeps/unix/sysv/linux/arm/le/libc.abilist
+++ b/sysdeps/unix/sysv/linux/arm/le/libc.abilist
@@ -2733,3 +2733,4 @@  GLIBC_2.9 ns_name_skip F
 GLIBC_2.9 ns_name_uncompress F
 GLIBC_2.9 ns_name_unpack F
 GLIBC_2.9 pipe2 F
+GLIBC_3.5 __memcmpeq F
\ No newline at end of file
diff --git a/sysdeps/unix/sysv/linux/csky/libc.abilist b/sysdeps/unix/sysv/linux/csky/libc.abilist
index b7676eb372..70cd0ff05e 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_3.5 __memcmpeq F
\ No newline at end of file
diff --git a/sysdeps/unix/sysv/linux/hppa/libc.abilist b/sysdeps/unix/sysv/linux/hppa/libc.abilist
index f6965c9d95..7056d3e4d6 100644
--- a/sysdeps/unix/sysv/linux/hppa/libc.abilist
+++ b/sysdeps/unix/sysv/linux/hppa/libc.abilist
@@ -2755,3 +2755,4 @@  GLIBC_2.9 ns_name_skip F
 GLIBC_2.9 ns_name_uncompress F
 GLIBC_2.9 ns_name_unpack F
 GLIBC_2.9 pipe2 F
+GLIBC_3.5 __memcmpeq F
\ No newline at end of file
diff --git a/sysdeps/unix/sysv/linux/i386/libc.abilist b/sysdeps/unix/sysv/linux/i386/libc.abilist
index 2e7603d9ed..8ffd4c2832 100644
--- a/sysdeps/unix/sysv/linux/i386/libc.abilist
+++ b/sysdeps/unix/sysv/linux/i386/libc.abilist
@@ -2939,3 +2939,4 @@  GLIBC_2.9 ns_name_skip F
 GLIBC_2.9 ns_name_uncompress F
 GLIBC_2.9 ns_name_unpack F
 GLIBC_2.9 pipe2 F
+GLIBC_3.5 __memcmpeq F
\ No newline at end of file
diff --git a/sysdeps/unix/sysv/linux/ia64/libc.abilist b/sysdeps/unix/sysv/linux/ia64/libc.abilist
index dd3a56d3fe..f8c405a3c1 100644
--- a/sysdeps/unix/sysv/linux/ia64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/ia64/libc.abilist
@@ -2706,3 +2706,4 @@  GLIBC_2.9 ns_name_skip F
 GLIBC_2.9 ns_name_uncompress F
 GLIBC_2.9 ns_name_unpack F
 GLIBC_2.9 pipe2 F
+GLIBC_3.5 __memcmpeq F
\ No newline at end of file
diff --git a/sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist b/sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist
index c1e0ea9c10..c8b7557d26 100644
--- a/sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist
+++ b/sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist
@@ -2715,3 +2715,4 @@  GLIBC_2.9 ns_name_skip F
 GLIBC_2.9 ns_name_uncompress F
 GLIBC_2.9 ns_name_unpack F
 GLIBC_2.9 pipe2 F
+GLIBC_3.5 __memcmpeq F
\ No newline at end of file
diff --git a/sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist b/sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist
index 93161048ca..94f983248b 100644
--- a/sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist
+++ b/sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist
@@ -2882,3 +2882,4 @@  GLIBC_2.9 ns_name_skip F
 GLIBC_2.9 ns_name_uncompress F
 GLIBC_2.9 ns_name_unpack F
 GLIBC_2.9 pipe2 F
+GLIBC_3.5 __memcmpeq F
\ No newline at end of file
diff --git a/sysdeps/unix/sysv/linux/microblaze/be/libc.abilist b/sysdeps/unix/sysv/linux/microblaze/be/libc.abilist
index 0aaeec8a27..87f62551fe 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_3.5 __memcmpeq F
\ No newline at end of file
diff --git a/sysdeps/unix/sysv/linux/microblaze/le/libc.abilist b/sysdeps/unix/sysv/linux/microblaze/le/libc.abilist
index bec5f456c9..a30ddf68ef 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_3.5 __memcmpeq F
\ No newline at end of file
diff --git a/sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist b/sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist
index 97d2127f78..e54c14ccd1 100644
--- a/sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist
+++ b/sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist
@@ -2843,3 +2843,4 @@  GLIBC_2.9 ns_name_skip F
 GLIBC_2.9 ns_name_uncompress F
 GLIBC_2.9 ns_name_unpack F
 GLIBC_2.9 pipe2 F
+GLIBC_3.5 __memcmpeq F
\ No newline at end of file
diff --git a/sysdeps/unix/sysv/linux/mips/mips32/nofpu/libc.abilist b/sysdeps/unix/sysv/linux/mips/mips32/nofpu/libc.abilist
index acb0756c11..38aba84dc5 100644
--- a/sysdeps/unix/sysv/linux/mips/mips32/nofpu/libc.abilist
+++ b/sysdeps/unix/sysv/linux/mips/mips32/nofpu/libc.abilist
@@ -2841,3 +2841,4 @@  GLIBC_2.9 ns_name_skip F
 GLIBC_2.9 ns_name_uncompress F
 GLIBC_2.9 ns_name_unpack F
 GLIBC_2.9 pipe2 F
+GLIBC_3.5 __memcmpeq F
\ No newline at end of file
diff --git a/sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist b/sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist
index ebc21dde1e..a3605989e3 100644
--- a/sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist
+++ b/sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist
@@ -2849,3 +2849,4 @@  GLIBC_2.9 ns_name_skip F
 GLIBC_2.9 ns_name_uncompress F
 GLIBC_2.9 ns_name_unpack F
 GLIBC_2.9 pipe2 F
+GLIBC_3.5 __memcmpeq F
\ No newline at end of file
diff --git a/sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist b/sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist
index c68f7e3c6c..e6ffe45977 100644
--- a/sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist
@@ -2753,3 +2753,4 @@  GLIBC_2.9 ns_name_skip F
 GLIBC_2.9 ns_name_uncompress F
 GLIBC_2.9 ns_name_unpack F
 GLIBC_2.9 pipe2 F
+GLIBC_3.5 __memcmpeq F
\ No newline at end of file
diff --git a/sysdeps/unix/sysv/linux/nios2/libc.abilist b/sysdeps/unix/sysv/linux/nios2/libc.abilist
index e5b6834f14..16776a5d25 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_3.5 __memcmpeq F
\ No newline at end of file
diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist b/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist
index 132707c8ad..8dd99682a9 100644
--- a/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist
@@ -3080,3 +3080,4 @@  GLIBC_2.9 ns_name_skip F
 GLIBC_2.9 ns_name_uncompress F
 GLIBC_2.9 ns_name_unpack F
 GLIBC_2.9 pipe2 F
+GLIBC_3.5 __memcmpeq F
\ No newline at end of file
diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist b/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist
index 0af2be31a0..306c194aca 100644
--- a/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist
@@ -3125,3 +3125,4 @@  GLIBC_2.9 ns_name_skip F
 GLIBC_2.9 ns_name_uncompress F
 GLIBC_2.9 ns_name_unpack F
 GLIBC_2.9 pipe2 F
+GLIBC_3.5 __memcmpeq F
\ No newline at end of file
diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc64/be/libc.abilist b/sysdeps/unix/sysv/linux/powerpc/powerpc64/be/libc.abilist
index cf864632d0..a8e24f6aae 100644
--- a/sysdeps/unix/sysv/linux/powerpc/powerpc64/be/libc.abilist
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc64/be/libc.abilist
@@ -2836,3 +2836,4 @@  GLIBC_2.9 ns_name_skip F
 GLIBC_2.9 ns_name_uncompress F
 GLIBC_2.9 ns_name_unpack F
 GLIBC_2.9 pipe2 F
+GLIBC_3.5 __memcmpeq F
\ No newline at end of file
diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc64/le/libc.abilist b/sysdeps/unix/sysv/linux/powerpc/powerpc64/le/libc.abilist
index d566d675d0..f47d906947 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_3.5 __memcmpeq F
\ No newline at end of file
diff --git a/sysdeps/unix/sysv/linux/riscv/rv32/libc.abilist b/sysdeps/unix/sysv/linux/riscv/rv32/libc.abilist
index c9a7eacb32..87b8554999 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_3.5 __memcmpeq F
\ No newline at end of file
diff --git a/sysdeps/unix/sysv/linux/riscv/rv64/libc.abilist b/sysdeps/unix/sysv/linux/riscv/rv64/libc.abilist
index 8299131cb2..65147c4596 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_3.5 __memcmpeq F
\ No newline at end of file
diff --git a/sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist b/sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist
index c3fe78f77f..d71ddcb6a5 100644
--- a/sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist
+++ b/sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist
@@ -3092,3 +3092,4 @@  GLIBC_2.9 pututline F
 GLIBC_2.9 pututxline F
 GLIBC_2.9 updwtmp F
 GLIBC_2.9 updwtmpx F
+GLIBC_3.5 __memcmpeq F
\ No newline at end of file
diff --git a/sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist b/sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist
index 83e542aa8c..88ae19acae 100644
--- a/sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist
@@ -2871,3 +2871,4 @@  GLIBC_2.9 ns_name_skip F
 GLIBC_2.9 ns_name_uncompress F
 GLIBC_2.9 ns_name_unpack F
 GLIBC_2.9 pipe2 F
+GLIBC_3.5 __memcmpeq F
\ No newline at end of file
diff --git a/sysdeps/unix/sysv/linux/sh/be/libc.abilist b/sysdeps/unix/sysv/linux/sh/be/libc.abilist
index dc502f6833..5609329d85 100644
--- a/sysdeps/unix/sysv/linux/sh/be/libc.abilist
+++ b/sysdeps/unix/sysv/linux/sh/be/libc.abilist
@@ -2762,3 +2762,4 @@  GLIBC_2.9 ns_name_skip F
 GLIBC_2.9 ns_name_uncompress F
 GLIBC_2.9 ns_name_unpack F
 GLIBC_2.9 pipe2 F
+GLIBC_3.5 __memcmpeq F
\ No newline at end of file
diff --git a/sysdeps/unix/sysv/linux/sh/le/libc.abilist b/sysdeps/unix/sysv/linux/sh/le/libc.abilist
index cba1abb556..f3ce30fcc5 100644
--- a/sysdeps/unix/sysv/linux/sh/le/libc.abilist
+++ b/sysdeps/unix/sysv/linux/sh/le/libc.abilist
@@ -2759,3 +2759,4 @@  GLIBC_2.9 ns_name_skip F
 GLIBC_2.9 ns_name_uncompress F
 GLIBC_2.9 ns_name_unpack F
 GLIBC_2.9 pipe2 F
+GLIBC_3.5 __memcmpeq F
\ No newline at end of file
diff --git a/sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist b/sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist
index d4a516fb47..8d67b75244 100644
--- a/sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist
+++ b/sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist
@@ -3097,3 +3097,4 @@  GLIBC_2.9 ns_name_skip F
 GLIBC_2.9 ns_name_uncompress F
 GLIBC_2.9 ns_name_unpack F
 GLIBC_2.9 pipe2 F
+GLIBC_3.5 __memcmpeq F
\ No newline at end of file
diff --git a/sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist b/sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist
index 6268875ba3..999e7c1f05 100644
--- a/sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist
@@ -2729,3 +2729,4 @@  GLIBC_2.9 ns_name_skip F
 GLIBC_2.9 ns_name_uncompress F
 GLIBC_2.9 ns_name_unpack F
 GLIBC_2.9 pipe2 F
+GLIBC_3.5 __memcmpeq F
\ No newline at end of file
diff --git a/sysdeps/unix/sysv/linux/x86_64/64/libc.abilist b/sysdeps/unix/sysv/linux/x86_64/64/libc.abilist
index 095e914b73..c5be6ef43e 100644
--- a/sysdeps/unix/sysv/linux/x86_64/64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/x86_64/64/libc.abilist
@@ -2680,3 +2680,4 @@  GLIBC_2.9 ns_name_skip F
 GLIBC_2.9 ns_name_uncompress F
 GLIBC_2.9 ns_name_unpack F
 GLIBC_2.9 pipe2 F
+GLIBC_3.5 __memcmpeq F
\ No newline at end of file
diff --git a/sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist b/sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist
index dd910f7fe9..cc16ae6335 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_3.5 __memcmpeq F
\ No newline at end of file
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..9cc4750bbc 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)