diff --git a/ChangeLog b/ChangeLog
index 7acf5caabb..62e49bb03a 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,71 @@
+2016-12-02  Joseph Myers  <joseph@codesourcery.com>
+
+	* math/bits/mathcalls.h [__GLIBC_USE (IEC_60559_BFP_EXT)] (llogb):
+	New declaration.
+	* math/tgmath.h [__GLIBC_USE (IEC_60559_BFP_EXT)] (llogb): New
+	macro.
+	* math/math.h [__GLIBC_USE (IEC_60559_BFP_EXT)] (__FP_LONG_MAX):
+	New macro.
+	[__GLIBC_USE (IEC_60559_BFP_EXT)] (FP_LLOGB0): Likewise.
+	[__GLIBC_USE (IEC_60559_BFP_EXT)] (FP_LLOGBNAN): Likewise.
+	* math/Versions (llogb): New libm symbol at version GLIBC_2.25.
+	(llogbf): Likewise.
+	(llogbl): Likewise.
+	* math/Makefile (gen-libm-calls): Add w_llogbF.
+	(tests): Add test-fp-llogb-constants.
+	* math/w_llogb_template.c: New file.  Based on
+	math/w_ilogb_template.c.
+	* math/libm-test.inc (llogb_test_data): New array.
+	(llogb_test): New function.
+	(main): Call llogb_test.
+	* math/test-fp-llogb-constants.c: New file.  Based on
+	math/test-fp-ilogb-constants.c.
+	* math/test-tgmath-ret.c (llogb): New CHECK_RET_CONST call.
+	(do_test): Call check_return_llogb.
+	* math/test-tgmath.c (NCALLS): Increase to 126.
+	(F(compile_test)): Call llogb.
+	(F(llogb)): New function.
+	* manual/math.texi (Exponents and Logarithms): Document llogb,
+	llogbf, llogbl, FP_LLOGB0 and FP_LLOGBNAN.
+	* manual/libm-err-tab.pl (@all_functions): Add llogb.
+	* sysdeps/ieee754/ldbl-opt/nldbl-llogb.c: New file.
+	* sysdeps/ieee754/ldbl-opt/w_llogbl.c: Likewise.
+	* sysdeps/ieee754/ldbl-opt/Makefile (libnldbl-calls): Add llogb.
+	(CFLAGS-nldbl-llogb.c): New variable.
+	* sysdeps/nacl/libm.abilist: Update.
+	* sysdeps/unix/sysv/linux/aarch64/libm.abilist: Likewise.
+	* sysdeps/unix/sysv/linux/alpha/libm.abilist: Likewise.
+	* sysdeps/unix/sysv/linux/arm/libm.abilist: Likewise.
+	* sysdeps/unix/sysv/linux/hppa/libm.abilist: Likewise.
+	* sysdeps/unix/sysv/linux/i386/libm.abilist: Likewise.
+	* sysdeps/unix/sysv/linux/ia64/libm.abilist: Likewise.
+	* sysdeps/unix/sysv/linux/m68k/coldfire/libm.abilist: Likewise.
+	* sysdeps/unix/sysv/linux/m68k/m680x0/libm.abilist: Likewise.
+	* sysdeps/unix/sysv/linux/microblaze/libm.abilist: Likewise.
+	* sysdeps/unix/sysv/linux/mips/mips32/libm.abilist: Likewise.
+	* sysdeps/unix/sysv/linux/mips/mips64/libm.abilist: Likewise.
+	* sysdeps/unix/sysv/linux/nios2/libm.abilist: Likewise.
+	* sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libm.abilist:
+	Likewise.
+	* sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libm.abilist:
+	Likewise.
+	* sysdeps/unix/sysv/linux/powerpc/powerpc64/libm-le.abilist:
+	Likewise.
+	* sysdeps/unix/sysv/linux/powerpc/powerpc64/libm.abilist:
+	Likewise.
+	* sysdeps/unix/sysv/linux/s390/s390-32/libm.abilist: Likewise.
+	* sysdeps/unix/sysv/linux/s390/s390-64/libm.abilist: Likewise.
+	* sysdeps/unix/sysv/linux/sh/libm.abilist: Likewise.
+	* sysdeps/unix/sysv/linux/sparc/sparc32/libm.abilist: Likewise.
+	* sysdeps/unix/sysv/linux/sparc/sparc64/libm.abilist: Likewise.
+	* sysdeps/unix/sysv/linux/tile/tilegx/tilegx32/libm.abilist:
+	Likewise.
+	* sysdeps/unix/sysv/linux/tile/tilegx/tilegx64/libm.abilist:
+	Likewise.
+	* sysdeps/unix/sysv/linux/tile/tilepro/libm.abilist: Likewise.
+	* sysdeps/unix/sysv/linux/x86_64/64/libm.abilist: Likewise.
+	* sysdeps/unix/sysv/linux/x86_64/x32/libm.abilist: Likewise.
+
 2016-12-01  Joseph Myers  <joseph@codesourcery.com>
 
 	* sysdeps/ieee754/ldbl-128/s_getpayloadl.c (getpayloadl): Use
diff --git a/NEWS b/NEWS
index b2a0b0f1f8..c2e973d183 100644
--- a/NEWS
+++ b/NEWS
@@ -53,6 +53,9 @@ Version 2.25
 
   - Signaling NaN macros: SNANF, SNAN, SNANL.
 
+  - llogb functions: the llogb, llogbf and llogbl functions, and the
+    FP_LLOGB0 and FP_LLOGBNAN macros.
+
   - Comparison macros: iseqsig.
 
   - Classification macros: iscanonical, issubnormal, iszero.
diff --git a/manual/libm-err-tab.pl b/manual/libm-err-tab.pl
index 6d0bffc372..0e83853949 100755
--- a/manual/libm-err-tab.pl
+++ b/manual/libm-err-tab.pl
@@ -58,7 +58,7 @@ use vars qw (%results @all_floats %suffices @all_functions);
     "creal", "csin", "csinh", "csqrt", "ctan", "ctanh", "erf", "erfc",
     "exp", "exp10", "exp2", "expm1", "fabs", "fdim", "floor", "fma",
     "fmax", "fmin", "fmod", "frexp", "gamma", "hypot",
-    "ilogb", "j0", "j1", "jn", "lgamma", "lrint",
+    "ilogb", "j0", "j1", "jn", "lgamma", "llogb", "lrint",
     "llrint", "log", "log10", "log1p", "log2", "logb", "lround",
     "llround", "modf", "nearbyint", "nextafter", "nextdown", "nexttoward",
     "nextup", "pow", "remainder", "remquo", "rint", "round", "scalb",
diff --git a/manual/math.texi b/manual/math.texi
index b4bb32345e..5ad8732eca 100644
--- a/manual/math.texi
+++ b/manual/math.texi
@@ -584,9 +584,20 @@ negative), @code{logb} returns @math{@infinity{}}.  If @var{x} is zero,
 @comment math.h
 @comment ISO
 @deftypefunx int ilogbl (long double @var{x})
+@comment math.h
+@comment ISO
+@deftypefunx {long int} llogb (double @var{x})
+@comment math.h
+@comment ISO
+@deftypefunx {long int} llogbf (float @var{x})
+@comment math.h
+@comment ISO
+@deftypefunx {long int} llogbl (long double @var{x})
 @safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}}
 These functions are equivalent to the corresponding @code{logb}
-functions except that they return signed integer values.
+functions except that they return signed integer values.  The
+@code{ilogb} functions are from ISO C99; the @code{llogb} functions
+are from TS 18661-1:2014.
 @end deftypefun
 
 @noindent
@@ -603,6 +614,15 @@ numeric value is either @code{INT_MIN} or @code{-INT_MAX}.
 This macro is defined in @w{ISO C99}.
 @end deftypevr
 
+@comment math.h
+@comment ISO
+@deftypevr Macro {long int} FP_LLOGB0
+@code{llogb} returns this value if its argument is @code{0}.  The
+numeric value is either @code{LONG_MIN} or @code{-LONG_MAX}.
+
+This macro is defined in TS 18661-1:2014.
+@end deftypevr
+
 @comment math.h
 @comment ISO
 @deftypevr Macro int FP_ILOGBNAN
@@ -612,6 +632,15 @@ numeric value is either @code{INT_MIN} or @code{INT_MAX}.
 This macro is defined in @w{ISO C99}.
 @end deftypevr
 
+@comment math.h
+@comment ISO
+@deftypevr Macro {long int} FP_LLOGBNAN
+@code{llogb} returns this value if its argument is @code{NaN}.  The
+numeric value is either @code{LONG_MIN} or @code{LONG_MAX}.
+
+This macro is defined in TS 18661-1:2014.
+@end deftypevr
+
 These values are system specific.  They might even be the same.  The
 proper way to test the result of @code{ilogb} is as follows:
 
diff --git a/math/Makefile b/math/Makefile
index ac3a90a582..848b093863 100644
--- a/math/Makefile
+++ b/math/Makefile
@@ -52,7 +52,7 @@ gen-libm-calls = cargF conjF cimagF crealF cabsF s_cacosF		  \
 		 k_casinhF s_csinhF k_casinhF s_csinhF s_catanhF s_catanF \
 		 s_ctanF s_ctanhF s_cexpF s_clogF s_cprojF s_csqrtF	  \
 		 s_cpowF s_clog10F s_fdimF s_nextdownF s_fmaxF s_fminF	  \
-		 s_nanF s_iseqsigF s_canonicalizeF w_ilogbF
+		 s_nanF s_iseqsigF s_canonicalizeF w_ilogbF w_llogbF
 
 libm-calls =								  \
 	e_acosF e_acoshF e_asinF e_atan2F e_atanhF e_coshF e_expF e_fmodF \
@@ -159,7 +159,7 @@ tests = test-matherr test-fenv atest-exp atest-sincos atest-exp2 basic-test \
 	test-fesetexcept-traps test-fetestexceptflag test-femode \
 	test-femode-traps test-iszero-excess-precision \
 	test-iseqsig-excess-precision test-flt-eval-method \
-	test-fp-ilogb-constants $(tests-static)
+	test-fp-ilogb-constants test-fp-llogb-constants $(tests-static)
 tests-static = test-fpucw-static test-fpucw-ieee-static \
 	       test-signgam-uchar-static test-signgam-uchar-init-static \
 	       test-signgam-uint-static test-signgam-uint-init-static \
diff --git a/math/Versions b/math/Versions
index 143e53f052..6fe9bb7e6f 100644
--- a/math/Versions
+++ b/math/Versions
@@ -223,5 +223,6 @@ libm {
     canonicalize; canonicalizef; canonicalizel;
     setpayload; setpayloadf; setpayloadl;
     setpayloadsig; setpayloadsigf; setpayloadsigl;
+    llogb; llogbf; llogbl;
   }
 }
diff --git a/math/bits/mathcalls.h b/math/bits/mathcalls.h
index 54ea4b8f30..c57b5627cd 100644
--- a/math/bits/mathcalls.h
+++ b/math/bits/mathcalls.h
@@ -315,6 +315,11 @@ __MATHCALL (scalbn,, (_Mdouble_ __x, int __n));
 __MATHDECL (int,ilogb,, (_Mdouble_ __x));
 #endif
 
+#if __GLIBC_USE (IEC_60559_BFP_EXT)
+/* Like ilogb, but returning long int.  */
+__MATHDECL (long int, llogb,, (_Mdouble_ __x));
+#endif
+
 #ifdef __USE_ISOC99
 /* Return X times (2 to the Nth power).  */
 __MATHCALL (scalbln,, (_Mdouble_ __x, long int __n));
diff --git a/math/libm-test.inc b/math/libm-test.inc
index 81d114b04f..85df9deb86 100644
--- a/math/libm-test.inc
+++ b/math/libm-test.inc
@@ -50,7 +50,7 @@
    ilogb, iscanonical, isfinite, isinf, isnan, isnormal, issignaling,
    issubnormal, iszero, iseqsig, isless, islessequal, isgreater,
    isgreaterequal, islessgreater, isunordered, j0, j1, jn,
-   ldexp, lgamma, log, log10, log1p, log2, logb,
+   ldexp, lgamma, llogb, log, log10, log1p, log2, logb,
    modf, nearbyint, nextafter, nexttoward,
    pow, pow10, remainder, remquo, rint, lrint, llrint,
    round, lround, llround,
@@ -9171,6 +9171,48 @@ gamma_test (void)
 }
 
 
+static const struct test_f_l_data llogb_test_data[] =
+  {
+    TEST_f_l (llogb, 1, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+    TEST_f_l (llogb, lit_e, 1, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+    TEST_f_l (llogb, 1024, 10, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+    TEST_f_l (llogb, -2000, 10, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+    TEST_f_l (llogb, 0.5, -1, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED);
+    TEST_f_l (llogb, -0.5, -1, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED);
+
+#if MANT_DIG >= 57
+    TEST_f_l (llogb, 0x1.ffffffffffffffp1L, 1, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+    TEST_f_l (llogb, -0x1.ffffffffffffffp1L, 1, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+#endif
+
+    TEST_f_l (llogb, min_subnorm_value, MIN_EXP-MANT_DIG, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED);
+    TEST_f_l (llogb, -min_subnorm_value, MIN_EXP-MANT_DIG, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED);
+    TEST_f_l (llogb, min_value, MIN_EXP-1, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED);
+    TEST_f_l (llogb, -min_value, MIN_EXP-1, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED);
+    TEST_f_l (llogb, max_value, MAX_EXP-1, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED);
+    TEST_f_l (llogb, -max_value, MAX_EXP-1, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED);
+
+    /* llogb (0.0) == FP_LLOGB0 plus invalid exception  */
+    TEST_f_l (llogb, 0.0, FP_LLOGB0, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION|ERRNO_EDOM),
+    TEST_f_l (llogb, -0.0, FP_LLOGB0, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION|ERRNO_EDOM),
+    /* llogb (qNaN) == FP_LLOGBNAN plus invalid exception  */
+    TEST_f_l (llogb, qnan_value, FP_LLOGBNAN, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION|ERRNO_EDOM),
+    TEST_f_l (llogb, -qnan_value, FP_LLOGBNAN, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION|ERRNO_EDOM),
+    TEST_f_l (llogb, snan_value, FP_LLOGBNAN, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION|ERRNO_EDOM),
+    TEST_f_l (llogb, -snan_value, FP_LLOGBNAN, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION|ERRNO_EDOM),
+    /* llogb (inf) == LONG_MAX plus invalid exception  */
+    TEST_f_l (llogb, plus_infty, LONG_MAX, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION|ERRNO_EDOM),
+    /* llogb (-inf) == LONG_MAX plus invalid exception  */
+    TEST_f_l (llogb, minus_infty, LONG_MAX, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION|ERRNO_EDOM),
+  };
+
+static void
+llogb_test (void)
+{
+  ALL_RM_TEST (llogb, 1, llogb_test_data, RUN_TEST_LOOP_f_l, END);
+}
+
+
 static const struct test_f_l_data lrint_test_data[] =
   {
     /* Bug 6798: errno setting may be missing.  */
@@ -13775,6 +13817,7 @@ main (int argc, char **argv)
   modf_test ();
   pow10_test ();
   ilogb_test ();
+  llogb_test ();
   scalb_test ();
   scalbn_test ();
   scalbln_test ();
diff --git a/math/math.h b/math/math.h
index 6e4bf9e528..b8f4b415c7 100644
--- a/math/math.h
+++ b/math/math.h
@@ -97,11 +97,13 @@ typedef _Float128x double_t;
 # endif
 #endif
 
-/* Define macros for the return value of ilogb, based on
+/* Define macros for the return values of ilogb and llogb, based on
    __FP_LOGB0_IS_MIN and __FP_LOGBNAN_IS_MIN.
 
     FP_ILOGB0	Expands to a value returned by `ilogb (0.0)'.
     FP_ILOGBNAN	Expands to a value returned by `ilogb (NAN)'.
+    FP_LLOGB0	Expands to a value returned by `llogb (0.0)'.
+    FP_LLOGBNAN	Expands to a value returned by `llogb (NAN)'.
 
 */
 
@@ -118,6 +120,23 @@ typedef _Float128x double_t;
 #  define FP_ILOGBNAN	2147483647
 # endif
 #endif
+#if __GLIBC_USE (IEC_60559_BFP_EXT)
+# if __WORDSIZE == 32
+#  define __FP_LONG_MAX 0x7fffffffL
+# else
+#  define __FP_LONG_MAX 0x7fffffffffffffffL
+# endif
+# if __FP_LOGB0_IS_MIN
+#  define FP_LLOGB0	(-__FP_LONG_MAX - 1)
+# else
+#  define FP_LLOGB0	(-__FP_LONG_MAX)
+# endif
+# if __FP_LOGBNAN_IS_MIN
+#  define FP_LLOGBNAN	(-__FP_LONG_MAX - 1)
+# else
+#  define FP_LLOGBNAN	__FP_LONG_MAX
+# endif
+#endif
 
 /* Get information about long double.  */
 
diff --git a/math/test-fp-llogb-constants.c b/math/test-fp-llogb-constants.c
new file mode 100644
index 0000000000..25bc0042f4
--- /dev/null
+++ b/math/test-fp-llogb-constants.c
@@ -0,0 +1,48 @@
+/* Test requirements on FP_LLOGB* constants.
+   Copyright (C) 2016 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <limits.h>
+#include <math.h>
+
+#if FP_LLOGB0 >= 0
+# error "FP_LLOGB0 is positive"
+#endif
+
+#if FP_LLOGB0 != LONG_MIN && FP_LLOGB0 != -LONG_MAX
+# error "FP_LLOGB0 must be LONG_MIN or -LONG_MAX"
+#endif
+
+#if FP_LLOGBNAN >= 0 && FP_LLOGBNAN != LONG_MAX
+# error "FP_LLOGBNAN must be LONG_MIN or LONG_MAX"
+#endif
+
+#if FP_LLOGBNAN < 0 && FP_LLOGBNAN != LONG_MIN
+# error "FP_LLOGBNAN must be LONG_MIN or LONG_MAX"
+#endif
+
+#if (FP_ILOGB0 == INT_MIN) != (FP_LLOGB0 == LONG_MIN)
+# error "FP_ILOGB0 and FP_LLOGB0 inconsistent"
+#endif
+
+#if (FP_ILOGBNAN == INT_MIN) != (FP_LLOGBNAN == LONG_MIN)
+# error "FP_ILOGBNAN and FP_LLOGBNAN inconsistent"
+#endif
+
+/* This is a compilation test.  */
+#define TEST_FUNCTION 0
+#include "../test-skeleton.c"
diff --git a/math/test-tgmath-ret.c b/math/test-tgmath-ret.c
index 9f535b9774..d7bcb5c1b2 100644
--- a/math/test-tgmath-ret.c
+++ b/math/test-tgmath-ret.c
@@ -61,6 +61,7 @@ check_return_ ##func (void)						      \
 }
 
 CHECK_RET_CONST(ilogb, int)
+CHECK_RET_CONST(llogb, long)
 CHECK_RET_CONST(lrint, long)
 CHECK_RET_CONST(lround, long)
 CHECK_RET_CONST(llrint, long long)
@@ -70,6 +71,7 @@ static int
 do_test (void)
 {
   check_return_ilogb ();
+  check_return_llogb ();
   check_return_lrint ();
   check_return_lround ();
   check_return_llrint ();
diff --git a/math/test-tgmath.c b/math/test-tgmath.c
index a919c64aab..be2c2fc3d4 100644
--- a/math/test-tgmath.c
+++ b/math/test-tgmath.c
@@ -50,7 +50,7 @@ int count_cdouble;
 int count_cfloat;
 int count_cldouble;
 
-#define NCALLS     125
+#define NCALLS     126
 #define NCALLS_INT 4
 #define NCCALLS    47
 
@@ -281,6 +281,7 @@ F(compile_test) (void)
   a = scalb (scalb (x, a), (TYPE) (6));
   k = scalbn (a, 7) + scalbln (c, 10l);
   i = ilogb (x);
+  j = llogb (x);
   a = fdim (fdim (x, a), fdim (c, b));
   b = fmax (fmax (a, x), fmax (c, b));
   a = fmin (fmin (x, a), fmin (c, b));
@@ -379,6 +380,7 @@ F(compile_test) (void)
       a = scalb (y, (const TYPE) (6));
       k = scalbn (y, 7) + scalbln (y, 10l);
       i = ilogb (y);
+      j = llogb (y);
       a = fdim (y, y);
       a = fmax (y, y);
       a = fmin (y, y);
@@ -846,6 +848,14 @@ int
   return x;
 }
 
+long int
+(F(llogb)) (TYPE x)
+{
+  ++count;
+  P ();
+  return x;
+}
+
 TYPE
 (F(fdim)) (TYPE x, TYPE y)
 {
diff --git a/math/tgmath.h b/math/tgmath.h
index 0d51ae60be..95f5f198ba 100644
--- a/math/tgmath.h
+++ b/math/tgmath.h
@@ -438,6 +438,9 @@
      __TGMATH_TERNARY_REAL_ONLY (Val1, Val2, Val3, fma)
 
 #if __GLIBC_USE (IEC_60559_BFP_EXT)
+/* Like ilogb, but returning long int.  */
+#define llogb(Val) __TGMATH_UNARY_REAL_RET_ONLY (Val, long int, llogb)
+
 /* Total order operation.  */
 # define totalorder(Val1, Val2) __TGMATH_BINARY_REAL_ONLY (Val1, Val2,	\
 							   totalorder)
diff --git a/math/w_llogb_template.c b/math/w_llogb_template.c
new file mode 100644
index 0000000000..9065bf9b4f
--- /dev/null
+++ b/math/w_llogb_template.c
@@ -0,0 +1,46 @@
+/* Wrapper to implement llogb in terms of ilogb.
+   Copyright (C) 2012-2016 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <math.h>
+#include <errno.h>
+#include <limits.h>
+#include <math_private.h>
+
+long int
+M_DECL_FUNC (__llogb) (FLOAT x)
+{
+  int r = M_SUF (__ieee754_ilogb) (x);
+  long int lr = r;
+  if (__glibc_unlikely (r == FP_ILOGB0)
+      || __glibc_unlikely (r == FP_ILOGBNAN)
+      || __glibc_unlikely (r == INT_MAX))
+    {
+#if LONG_MAX != INT_MAX
+      if (r == FP_ILOGB0)
+	lr = FP_LLOGB0;
+      else if (r == FP_ILOGBNAN)
+	lr = FP_LLOGBNAN;
+      else
+	lr = LONG_MAX;
+#endif
+      __set_errno (EDOM);
+      __feraiseexcept (FE_INVALID);
+    }
+  return lr;
+}
+declare_mgen_alias (__llogb, llogb)
diff --git a/sysdeps/ieee754/ldbl-opt/Makefile b/sysdeps/ieee754/ldbl-opt/Makefile
index 9d45684ffb..ba13515c3e 100644
--- a/sysdeps/ieee754/ldbl-opt/Makefile
+++ b/sysdeps/ieee754/ldbl-opt/Makefile
@@ -43,7 +43,7 @@ libnldbl-calls = asprintf dprintf fprintf fscanf fwprintf fwscanf iovfscanf \
 		 isoc99_wscanf isoc99_fwscanf isoc99_swscanf \
 		 isoc99_vwscanf isoc99_vfwscanf isoc99_vswscanf \
 		 nextup nextdown totalorder totalordermag getpayload \
-		 canonicalize setpayload setpayloadsig
+		 canonicalize setpayload setpayloadsig llogb
 libnldbl-routines = $(libnldbl-calls:%=nldbl-%)
 libnldbl-inhibit-o = $(object-suffixes)
 libnldbl-static-only-routines = $(libnldbl-routines)
@@ -112,6 +112,7 @@ CFLAGS-nldbl-jn.c = -fno-builtin-jnl
 CFLAGS-nldbl-ldexp.c = -fno-builtin-ldexpl
 CFLAGS-nldbl-lgamma.c = -fno-builtin-lgammal
 CFLAGS-nldbl-lgamma_r.c = -fno-builtin-lgammal_r
+CFLAGS-nldbl-llogb.c = -fno-builtin-llogbl
 CFLAGS-nldbl-llrint.c = -fno-builtin-llrintl
 CFLAGS-nldbl-llround.c = -fno-builtin-llroundl
 CFLAGS-nldbl-log.c = -fno-builtin-logl
diff --git a/sysdeps/ieee754/ldbl-opt/nldbl-llogb.c b/sysdeps/ieee754/ldbl-opt/nldbl-llogb.c
new file mode 100644
index 0000000000..2f241ddc58
--- /dev/null
+++ b/sysdeps/ieee754/ldbl-opt/nldbl-llogb.c
@@ -0,0 +1,26 @@
+/* Compatibility routine for IEEE double as long double for llogb.
+   Copyright (C) 2016 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include "nldbl-compat.h"
+
+long int
+attribute_hidden
+llogbl (double x)
+{
+  return llogb (x);
+}
diff --git a/sysdeps/ieee754/ldbl-opt/w_llogbl.c b/sysdeps/ieee754/ldbl-opt/w_llogbl.c
new file mode 100644
index 0000000000..8abe54bc85
--- /dev/null
+++ b/sysdeps/ieee754/ldbl-opt/w_llogbl.c
@@ -0,0 +1,5 @@
+/* llogbl is not subject to complex aliasing rules.  It was added in
+   glibc 2.25.  */
+#define declare_mgen_alias(from, to) weak_alias (M_SUF (from), M_SUF (to))
+#include <math-type-macros-ldouble.h>
+#include <w_llogb_template.c>
diff --git a/sysdeps/nacl/libm.abilist b/sysdeps/nacl/libm.abilist
index 7a256f8910..0c0e352c79 100644
--- a/sysdeps/nacl/libm.abilist
+++ b/sysdeps/nacl/libm.abilist
@@ -392,6 +392,9 @@ GLIBC_2.25 fetestexceptflag F
 GLIBC_2.25 getpayload F
 GLIBC_2.25 getpayloadf F
 GLIBC_2.25 getpayloadl F
+GLIBC_2.25 llogb F
+GLIBC_2.25 llogbf F
+GLIBC_2.25 llogbl F
 GLIBC_2.25 setpayload F
 GLIBC_2.25 setpayloadf F
 GLIBC_2.25 setpayloadl F
diff --git a/sysdeps/unix/sysv/linux/aarch64/libm.abilist b/sysdeps/unix/sysv/linux/aarch64/libm.abilist
index 689bd0a80d..b8ab6fcdd0 100644
--- a/sysdeps/unix/sysv/linux/aarch64/libm.abilist
+++ b/sysdeps/unix/sysv/linux/aarch64/libm.abilist
@@ -424,6 +424,9 @@ GLIBC_2.25 fetestexceptflag F
 GLIBC_2.25 getpayload F
 GLIBC_2.25 getpayloadf F
 GLIBC_2.25 getpayloadl F
+GLIBC_2.25 llogb F
+GLIBC_2.25 llogbf F
+GLIBC_2.25 llogbl F
 GLIBC_2.25 setpayload F
 GLIBC_2.25 setpayloadf F
 GLIBC_2.25 setpayloadl F
diff --git a/sysdeps/unix/sysv/linux/alpha/libm.abilist b/sysdeps/unix/sysv/linux/alpha/libm.abilist
index 9f4b50df12..604c996e78 100644
--- a/sysdeps/unix/sysv/linux/alpha/libm.abilist
+++ b/sysdeps/unix/sysv/linux/alpha/libm.abilist
@@ -434,6 +434,9 @@ GLIBC_2.25 fetestexceptflag F
 GLIBC_2.25 getpayload F
 GLIBC_2.25 getpayloadf F
 GLIBC_2.25 getpayloadl F
+GLIBC_2.25 llogb F
+GLIBC_2.25 llogbf F
+GLIBC_2.25 llogbl F
 GLIBC_2.25 setpayload F
 GLIBC_2.25 setpayloadf F
 GLIBC_2.25 setpayloadl F
diff --git a/sysdeps/unix/sysv/linux/arm/libm.abilist b/sysdeps/unix/sysv/linux/arm/libm.abilist
index 8d0905db1b..618cb6fce1 100644
--- a/sysdeps/unix/sysv/linux/arm/libm.abilist
+++ b/sysdeps/unix/sysv/linux/arm/libm.abilist
@@ -81,6 +81,9 @@ GLIBC_2.25 fetestexceptflag F
 GLIBC_2.25 getpayload F
 GLIBC_2.25 getpayloadf F
 GLIBC_2.25 getpayloadl F
+GLIBC_2.25 llogb F
+GLIBC_2.25 llogbf F
+GLIBC_2.25 llogbl F
 GLIBC_2.25 setpayload F
 GLIBC_2.25 setpayloadf F
 GLIBC_2.25 setpayloadl F
diff --git a/sysdeps/unix/sysv/linux/hppa/libm.abilist b/sysdeps/unix/sysv/linux/hppa/libm.abilist
index edf87c30f8..33314ad754 100644
--- a/sysdeps/unix/sysv/linux/hppa/libm.abilist
+++ b/sysdeps/unix/sysv/linux/hppa/libm.abilist
@@ -393,6 +393,9 @@ GLIBC_2.25 fetestexceptflag F
 GLIBC_2.25 getpayload F
 GLIBC_2.25 getpayloadf F
 GLIBC_2.25 getpayloadl F
+GLIBC_2.25 llogb F
+GLIBC_2.25 llogbf F
+GLIBC_2.25 llogbl F
 GLIBC_2.25 setpayload F
 GLIBC_2.25 setpayloadf F
 GLIBC_2.25 setpayloadl F
diff --git a/sysdeps/unix/sysv/linux/i386/libm.abilist b/sysdeps/unix/sysv/linux/i386/libm.abilist
index a139f50b87..4530ad538a 100644
--- a/sysdeps/unix/sysv/linux/i386/libm.abilist
+++ b/sysdeps/unix/sysv/linux/i386/libm.abilist
@@ -437,6 +437,9 @@ GLIBC_2.25 fetestexceptflag F
 GLIBC_2.25 getpayload F
 GLIBC_2.25 getpayloadf F
 GLIBC_2.25 getpayloadl F
+GLIBC_2.25 llogb F
+GLIBC_2.25 llogbf F
+GLIBC_2.25 llogbl F
 GLIBC_2.25 setpayload F
 GLIBC_2.25 setpayloadf F
 GLIBC_2.25 setpayloadl F
diff --git a/sysdeps/unix/sysv/linux/ia64/libm.abilist b/sysdeps/unix/sysv/linux/ia64/libm.abilist
index 166e0a94bb..9b94be0492 100644
--- a/sysdeps/unix/sysv/linux/ia64/libm.abilist
+++ b/sysdeps/unix/sysv/linux/ia64/libm.abilist
@@ -366,6 +366,9 @@ GLIBC_2.25 fetestexceptflag F
 GLIBC_2.25 getpayload F
 GLIBC_2.25 getpayloadf F
 GLIBC_2.25 getpayloadl F
+GLIBC_2.25 llogb F
+GLIBC_2.25 llogbf F
+GLIBC_2.25 llogbl F
 GLIBC_2.25 setpayload F
 GLIBC_2.25 setpayloadf F
 GLIBC_2.25 setpayloadl F
diff --git a/sysdeps/unix/sysv/linux/m68k/coldfire/libm.abilist b/sysdeps/unix/sysv/linux/m68k/coldfire/libm.abilist
index 8d0905db1b..618cb6fce1 100644
--- a/sysdeps/unix/sysv/linux/m68k/coldfire/libm.abilist
+++ b/sysdeps/unix/sysv/linux/m68k/coldfire/libm.abilist
@@ -81,6 +81,9 @@ GLIBC_2.25 fetestexceptflag F
 GLIBC_2.25 getpayload F
 GLIBC_2.25 getpayloadf F
 GLIBC_2.25 getpayloadl F
+GLIBC_2.25 llogb F
+GLIBC_2.25 llogbf F
+GLIBC_2.25 llogbl F
 GLIBC_2.25 setpayload F
 GLIBC_2.25 setpayloadf F
 GLIBC_2.25 setpayloadl F
diff --git a/sysdeps/unix/sysv/linux/m68k/m680x0/libm.abilist b/sysdeps/unix/sysv/linux/m68k/m680x0/libm.abilist
index f64023783e..6d61d704a1 100644
--- a/sysdeps/unix/sysv/linux/m68k/m680x0/libm.abilist
+++ b/sysdeps/unix/sysv/linux/m68k/m680x0/libm.abilist
@@ -435,6 +435,9 @@ GLIBC_2.25 fetestexceptflag F
 GLIBC_2.25 getpayload F
 GLIBC_2.25 getpayloadf F
 GLIBC_2.25 getpayloadl F
+GLIBC_2.25 llogb F
+GLIBC_2.25 llogbf F
+GLIBC_2.25 llogbl F
 GLIBC_2.25 setpayload F
 GLIBC_2.25 setpayloadf F
 GLIBC_2.25 setpayloadl F
diff --git a/sysdeps/unix/sysv/linux/microblaze/libm.abilist b/sysdeps/unix/sysv/linux/microblaze/libm.abilist
index d4c8749e1b..b55f6aaf86 100644
--- a/sysdeps/unix/sysv/linux/microblaze/libm.abilist
+++ b/sysdeps/unix/sysv/linux/microblaze/libm.abilist
@@ -392,6 +392,9 @@ GLIBC_2.25 fetestexceptflag F
 GLIBC_2.25 getpayload F
 GLIBC_2.25 getpayloadf F
 GLIBC_2.25 getpayloadl F
+GLIBC_2.25 llogb F
+GLIBC_2.25 llogbf F
+GLIBC_2.25 llogbl F
 GLIBC_2.25 setpayload F
 GLIBC_2.25 setpayloadf F
 GLIBC_2.25 setpayloadl F
diff --git a/sysdeps/unix/sysv/linux/mips/mips32/libm.abilist b/sysdeps/unix/sysv/linux/mips/mips32/libm.abilist
index 53f995161a..5ebba1172c 100644
--- a/sysdeps/unix/sysv/linux/mips/mips32/libm.abilist
+++ b/sysdeps/unix/sysv/linux/mips/mips32/libm.abilist
@@ -394,6 +394,9 @@ GLIBC_2.25 fetestexceptflag F
 GLIBC_2.25 getpayload F
 GLIBC_2.25 getpayloadf F
 GLIBC_2.25 getpayloadl F
+GLIBC_2.25 llogb F
+GLIBC_2.25 llogbf F
+GLIBC_2.25 llogbl F
 GLIBC_2.25 setpayload F
 GLIBC_2.25 setpayloadf F
 GLIBC_2.25 setpayloadl F
diff --git a/sysdeps/unix/sysv/linux/mips/mips64/libm.abilist b/sysdeps/unix/sysv/linux/mips/mips64/libm.abilist
index 6fa6b46f82..cf28ab6961 100644
--- a/sysdeps/unix/sysv/linux/mips/mips64/libm.abilist
+++ b/sysdeps/unix/sysv/linux/mips/mips64/libm.abilist
@@ -426,6 +426,9 @@ GLIBC_2.25 fetestexceptflag F
 GLIBC_2.25 getpayload F
 GLIBC_2.25 getpayloadf F
 GLIBC_2.25 getpayloadl F
+GLIBC_2.25 llogb F
+GLIBC_2.25 llogbf F
+GLIBC_2.25 llogbl F
 GLIBC_2.25 setpayload F
 GLIBC_2.25 setpayloadf F
 GLIBC_2.25 setpayloadl F
diff --git a/sysdeps/unix/sysv/linux/nios2/libm.abilist b/sysdeps/unix/sysv/linux/nios2/libm.abilist
index fd0839bb63..9d9fd05a5a 100644
--- a/sysdeps/unix/sysv/linux/nios2/libm.abilist
+++ b/sysdeps/unix/sysv/linux/nios2/libm.abilist
@@ -392,6 +392,9 @@ GLIBC_2.25 fetestexceptflag F
 GLIBC_2.25 getpayload F
 GLIBC_2.25 getpayloadf F
 GLIBC_2.25 getpayloadl F
+GLIBC_2.25 llogb F
+GLIBC_2.25 llogbf F
+GLIBC_2.25 llogbl F
 GLIBC_2.25 setpayload F
 GLIBC_2.25 setpayloadf F
 GLIBC_2.25 setpayloadl F
diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libm.abilist b/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libm.abilist
index a85c72fcef..2747628a52 100644
--- a/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libm.abilist
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libm.abilist
@@ -437,6 +437,9 @@ GLIBC_2.25 fetestexceptflag F
 GLIBC_2.25 getpayload F
 GLIBC_2.25 getpayloadf F
 GLIBC_2.25 getpayloadl F
+GLIBC_2.25 llogb F
+GLIBC_2.25 llogbf F
+GLIBC_2.25 llogbl F
 GLIBC_2.25 setpayload F
 GLIBC_2.25 setpayloadf F
 GLIBC_2.25 setpayloadl F
diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libm.abilist b/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libm.abilist
index b9e01662bc..26c115854a 100644
--- a/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libm.abilist
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libm.abilist
@@ -436,6 +436,9 @@ GLIBC_2.25 fetestexceptflag F
 GLIBC_2.25 getpayload F
 GLIBC_2.25 getpayloadf F
 GLIBC_2.25 getpayloadl F
+GLIBC_2.25 llogb F
+GLIBC_2.25 llogbf F
+GLIBC_2.25 llogbl F
 GLIBC_2.25 setpayload F
 GLIBC_2.25 setpayloadf F
 GLIBC_2.25 setpayloadl F
diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc64/libm-le.abilist b/sysdeps/unix/sysv/linux/powerpc/powerpc64/libm-le.abilist
index 615cbbc7c1..5f992b2df0 100644
--- a/sysdeps/unix/sysv/linux/powerpc/powerpc64/libm-le.abilist
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc64/libm-le.abilist
@@ -431,6 +431,9 @@ GLIBC_2.25 fetestexceptflag F
 GLIBC_2.25 getpayload F
 GLIBC_2.25 getpayloadf F
 GLIBC_2.25 getpayloadl F
+GLIBC_2.25 llogb F
+GLIBC_2.25 llogbf F
+GLIBC_2.25 llogbl F
 GLIBC_2.25 setpayload F
 GLIBC_2.25 setpayloadf F
 GLIBC_2.25 setpayloadl F
diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc64/libm.abilist b/sysdeps/unix/sysv/linux/powerpc/powerpc64/libm.abilist
index e5e30469c1..b4de7f182f 100644
--- a/sysdeps/unix/sysv/linux/powerpc/powerpc64/libm.abilist
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc64/libm.abilist
@@ -112,6 +112,9 @@ GLIBC_2.25 fetestexceptflag F
 GLIBC_2.25 getpayload F
 GLIBC_2.25 getpayloadf F
 GLIBC_2.25 getpayloadl F
+GLIBC_2.25 llogb F
+GLIBC_2.25 llogbf F
+GLIBC_2.25 llogbl F
 GLIBC_2.25 setpayload F
 GLIBC_2.25 setpayloadf F
 GLIBC_2.25 setpayloadl F
diff --git a/sysdeps/unix/sysv/linux/s390/s390-32/libm.abilist b/sysdeps/unix/sysv/linux/s390/s390-32/libm.abilist
index a523788800..67740c2c84 100644
--- a/sysdeps/unix/sysv/linux/s390/s390-32/libm.abilist
+++ b/sysdeps/unix/sysv/linux/s390/s390-32/libm.abilist
@@ -424,6 +424,9 @@ GLIBC_2.25 fetestexceptflag F
 GLIBC_2.25 getpayload F
 GLIBC_2.25 getpayloadf F
 GLIBC_2.25 getpayloadl F
+GLIBC_2.25 llogb F
+GLIBC_2.25 llogbf F
+GLIBC_2.25 llogbl F
 GLIBC_2.25 setpayload F
 GLIBC_2.25 setpayloadf F
 GLIBC_2.25 setpayloadl F
diff --git a/sysdeps/unix/sysv/linux/s390/s390-64/libm.abilist b/sysdeps/unix/sysv/linux/s390/s390-64/libm.abilist
index 2872dc3aa5..6fa99f01cf 100644
--- a/sysdeps/unix/sysv/linux/s390/s390-64/libm.abilist
+++ b/sysdeps/unix/sysv/linux/s390/s390-64/libm.abilist
@@ -422,6 +422,9 @@ GLIBC_2.25 fetestexceptflag F
 GLIBC_2.25 getpayload F
 GLIBC_2.25 getpayloadf F
 GLIBC_2.25 getpayloadl F
+GLIBC_2.25 llogb F
+GLIBC_2.25 llogbf F
+GLIBC_2.25 llogbl F
 GLIBC_2.25 setpayload F
 GLIBC_2.25 setpayloadf F
 GLIBC_2.25 setpayloadl F
diff --git a/sysdeps/unix/sysv/linux/sh/libm.abilist b/sysdeps/unix/sysv/linux/sh/libm.abilist
index 73f7ad905f..2c093afb63 100644
--- a/sysdeps/unix/sysv/linux/sh/libm.abilist
+++ b/sysdeps/unix/sysv/linux/sh/libm.abilist
@@ -393,6 +393,9 @@ GLIBC_2.25 fetestexceptflag F
 GLIBC_2.25 getpayload F
 GLIBC_2.25 getpayloadf F
 GLIBC_2.25 getpayloadl F
+GLIBC_2.25 llogb F
+GLIBC_2.25 llogbf F
+GLIBC_2.25 llogbl F
 GLIBC_2.25 setpayload F
 GLIBC_2.25 setpayloadf F
 GLIBC_2.25 setpayloadl F
diff --git a/sysdeps/unix/sysv/linux/sparc/sparc32/libm.abilist b/sysdeps/unix/sysv/linux/sparc/sparc32/libm.abilist
index 3f5186e145..515a6774eb 100644
--- a/sysdeps/unix/sysv/linux/sparc/sparc32/libm.abilist
+++ b/sysdeps/unix/sysv/linux/sparc/sparc32/libm.abilist
@@ -427,6 +427,9 @@ GLIBC_2.25 fetestexceptflag F
 GLIBC_2.25 getpayload F
 GLIBC_2.25 getpayloadf F
 GLIBC_2.25 getpayloadl F
+GLIBC_2.25 llogb F
+GLIBC_2.25 llogbf F
+GLIBC_2.25 llogbl F
 GLIBC_2.25 setpayload F
 GLIBC_2.25 setpayloadf F
 GLIBC_2.25 setpayloadl F
diff --git a/sysdeps/unix/sysv/linux/sparc/sparc64/libm.abilist b/sysdeps/unix/sysv/linux/sparc/sparc64/libm.abilist
index e1683dfdc0..1590b05966 100644
--- a/sysdeps/unix/sysv/linux/sparc/sparc64/libm.abilist
+++ b/sysdeps/unix/sysv/linux/sparc/sparc64/libm.abilist
@@ -425,6 +425,9 @@ GLIBC_2.25 fetestexceptflag F
 GLIBC_2.25 getpayload F
 GLIBC_2.25 getpayloadf F
 GLIBC_2.25 getpayloadl F
+GLIBC_2.25 llogb F
+GLIBC_2.25 llogbf F
+GLIBC_2.25 llogbl F
 GLIBC_2.25 setpayload F
 GLIBC_2.25 setpayloadf F
 GLIBC_2.25 setpayloadl F
diff --git a/sysdeps/unix/sysv/linux/tile/tilegx/tilegx32/libm.abilist b/sysdeps/unix/sysv/linux/tile/tilegx/tilegx32/libm.abilist
index 9e7008240e..3ed0c68120 100644
--- a/sysdeps/unix/sysv/linux/tile/tilegx/tilegx32/libm.abilist
+++ b/sysdeps/unix/sysv/linux/tile/tilegx/tilegx32/libm.abilist
@@ -393,6 +393,9 @@ GLIBC_2.25 fetestexceptflag F
 GLIBC_2.25 getpayload F
 GLIBC_2.25 getpayloadf F
 GLIBC_2.25 getpayloadl F
+GLIBC_2.25 llogb F
+GLIBC_2.25 llogbf F
+GLIBC_2.25 llogbl F
 GLIBC_2.25 setpayload F
 GLIBC_2.25 setpayloadf F
 GLIBC_2.25 setpayloadl F
diff --git a/sysdeps/unix/sysv/linux/tile/tilegx/tilegx64/libm.abilist b/sysdeps/unix/sysv/linux/tile/tilegx/tilegx64/libm.abilist
index 9e7008240e..3ed0c68120 100644
--- a/sysdeps/unix/sysv/linux/tile/tilegx/tilegx64/libm.abilist
+++ b/sysdeps/unix/sysv/linux/tile/tilegx/tilegx64/libm.abilist
@@ -393,6 +393,9 @@ GLIBC_2.25 fetestexceptflag F
 GLIBC_2.25 getpayload F
 GLIBC_2.25 getpayloadf F
 GLIBC_2.25 getpayloadl F
+GLIBC_2.25 llogb F
+GLIBC_2.25 llogbf F
+GLIBC_2.25 llogbl F
 GLIBC_2.25 setpayload F
 GLIBC_2.25 setpayloadf F
 GLIBC_2.25 setpayloadl F
diff --git a/sysdeps/unix/sysv/linux/tile/tilepro/libm.abilist b/sysdeps/unix/sysv/linux/tile/tilepro/libm.abilist
index 9e7008240e..3ed0c68120 100644
--- a/sysdeps/unix/sysv/linux/tile/tilepro/libm.abilist
+++ b/sysdeps/unix/sysv/linux/tile/tilepro/libm.abilist
@@ -393,6 +393,9 @@ GLIBC_2.25 fetestexceptflag F
 GLIBC_2.25 getpayload F
 GLIBC_2.25 getpayloadf F
 GLIBC_2.25 getpayloadl F
+GLIBC_2.25 llogb F
+GLIBC_2.25 llogbf F
+GLIBC_2.25 llogbl F
 GLIBC_2.25 setpayload F
 GLIBC_2.25 setpayloadf F
 GLIBC_2.25 setpayloadl F
diff --git a/sysdeps/unix/sysv/linux/x86_64/64/libm.abilist b/sysdeps/unix/sysv/linux/x86_64/64/libm.abilist
index 4b548a0856..908d6ffd39 100644
--- a/sysdeps/unix/sysv/linux/x86_64/64/libm.abilist
+++ b/sysdeps/unix/sysv/linux/x86_64/64/libm.abilist
@@ -426,6 +426,9 @@ GLIBC_2.25 fetestexceptflag F
 GLIBC_2.25 getpayload F
 GLIBC_2.25 getpayloadf F
 GLIBC_2.25 getpayloadl F
+GLIBC_2.25 llogb F
+GLIBC_2.25 llogbf F
+GLIBC_2.25 llogbl F
 GLIBC_2.25 setpayload F
 GLIBC_2.25 setpayloadf F
 GLIBC_2.25 setpayloadl F
diff --git a/sysdeps/unix/sysv/linux/x86_64/x32/libm.abilist b/sysdeps/unix/sysv/linux/x86_64/x32/libm.abilist
index 384a570623..cf5b5765fe 100644
--- a/sysdeps/unix/sysv/linux/x86_64/x32/libm.abilist
+++ b/sysdeps/unix/sysv/linux/x86_64/x32/libm.abilist
@@ -425,6 +425,9 @@ GLIBC_2.25 fetestexceptflag F
 GLIBC_2.25 getpayload F
 GLIBC_2.25 getpayloadf F
 GLIBC_2.25 getpayloadl F
+GLIBC_2.25 llogb F
+GLIBC_2.25 llogbf F
+GLIBC_2.25 llogbl F
 GLIBC_2.25 setpayload F
 GLIBC_2.25 setpayloadf F
 GLIBC_2.25 setpayloadl F