diff --git a/manual/math.texi b/manual/math.texi
index cf57937943..945b48d9fc 100644
--- a/manual/math.texi
+++ b/manual/math.texi
@@ -669,7 +669,8 @@ due to intermediate rounding.
 If @var{x} is de-normalized, @code{logb} returns the exponent @var{x}
 would have if it were normalized.  If @var{x} is infinity (positive or
 negative), @code{logb} returns @math{@infinity{}}.  If @var{x} is zero,
-@code{logb} returns @math{@infinity{}}.  It does not signal.
+a pole error occurs: @code{logb} raises the divide-by-zero exception,
+sets @code{errno} to @code{ERANGE} and returns @math{-@infinity{}}.
 @end deftypefun
 
 @deftypefun int ilogb (double @var{x})
diff --git a/math/libm-test-logb.inc b/math/libm-test-logb.inc
index 8399f52031..df8642bf21 100644
--- a/math/libm-test-logb.inc
+++ b/math/libm-test-logb.inc
@@ -23,10 +23,8 @@ static const struct test_f_f_data logb_test_data[] =
     TEST_f_f (logb, plus_infty, plus_infty, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
     TEST_f_f (logb, minus_infty, plus_infty, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
 
-    /* Bug 6793: errno setting may be missing.  */
-    TEST_f_f (logb, 0, minus_infty, NO_INEXACT_EXCEPTION|DIVIDE_BY_ZERO_EXCEPTION),
-
-    TEST_f_f (logb, minus_zero, minus_infty, NO_INEXACT_EXCEPTION|DIVIDE_BY_ZERO_EXCEPTION),
+    TEST_f_f (logb, 0, minus_infty, NO_INEXACT_EXCEPTION|DIVIDE_BY_ZERO_EXCEPTION|ERRNO_ERANGE),
+    TEST_f_f (logb, minus_zero, minus_infty, NO_INEXACT_EXCEPTION|DIVIDE_BY_ZERO_EXCEPTION|ERRNO_ERANGE),
     TEST_f_f (logb, qnan_value, qnan_value, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
     TEST_f_f (logb, -qnan_value, qnan_value, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
     TEST_f_f (logb, snan_value, qnan_value, NO_INEXACT_EXCEPTION|INVALID_EXCEPTION),
diff --git a/sysdeps/i386/fpu/s_logb.S b/sysdeps/i386/fpu/s_logb.S
deleted file mode 100644
index d1c7129248..0000000000
--- a/sysdeps/i386/fpu/s_logb.S
+++ /dev/null
@@ -1,16 +0,0 @@
-/*
- * Public domain.
- */
-
-#include <machine/asm.h>
-#include <libm-alias-double.h>
-
-RCSID("$NetBSD: s_logb.S,v 1.4 1995/05/09 00:14:30 jtc Exp $")
-
-ENTRY(__logb)
-	fldl	4(%esp)
-	fxtract
-	fstp	%st
-	ret
-END (__logb)
-libm_alias_double (__logb, logb)
diff --git a/sysdeps/i386/fpu/s_logbf.S b/sysdeps/i386/fpu/s_logbf.S
deleted file mode 100644
index 0d5e55d34f..0000000000
--- a/sysdeps/i386/fpu/s_logbf.S
+++ /dev/null
@@ -1,16 +0,0 @@
-/*
- * Public domain.
- */
-
-#include <machine/asm.h>
-#include <libm-alias-float.h>
-
-RCSID("$NetBSD: s_logbf.S,v 1.3 1995/05/09 00:15:12 jtc Exp $")
-
-ENTRY(__logbf)
-	flds	4(%esp)
-	fxtract
-	fstp	%st
-	ret
-END (__logbf)
-libm_alias_float (__logb, logb)
diff --git a/sysdeps/ieee754/dbl-64/s_logb.c b/sysdeps/ieee754/dbl-64/s_logb.c
index 49b88d2c8d..af4d56a2e7 100644
--- a/sysdeps/ieee754/dbl-64/s_logb.c
+++ b/sysdeps/ieee754/dbl-64/s_logb.c
@@ -20,11 +20,15 @@
 #include <math_private.h>
 #include <libm-alias-double.h>
 #include <fix-int-fp-convert-zero.h>
+#include "math_config.h"
 
 double
 __logb (double x)
 {
 #if USE_LOGB_BUILTIN
+  if (__glibc_unlikely (x == 0))
+    /* Pole error: logb (+-0).  */
+    return __math_divzero (1);
   return __builtin_logb (x);
 #else
   int64_t ix, ex;
@@ -32,7 +36,8 @@ __logb (double x)
   EXTRACT_WORDS64 (ix, x);
   ix &= UINT64_C(0x7fffffffffffffff);
   if (ix == 0)
-    return -1.0 / fabs (x);
+    /* Pole error: logb (+-0).  */
+    return __math_divzero (1);
   ex = ix >> 52;
   if (ex == 0x7ff)
     return x * x;
diff --git a/sysdeps/ieee754/flt-32/s_logbf.c b/sysdeps/ieee754/flt-32/s_logbf.c
index 29316e5787..f21a5b4123 100644
--- a/sysdeps/ieee754/flt-32/s_logbf.c
+++ b/sysdeps/ieee754/flt-32/s_logbf.c
@@ -16,11 +16,15 @@
 #include <math_private.h>
 #include <libm-alias-float.h>
 #include <fix-int-fp-convert-zero.h>
+#include "math_config.h"
 
 float
 __logbf (float x)
 {
 #if USE_LOGBF_BUILTIN
+  if (__glibc_unlikely (x == 0))
+    /* Pole error: logbf (+-0).  */
+    return __math_divzerof (1);
   return __builtin_logbf (x);
 #else
   int32_t ix, rix;
@@ -28,7 +32,8 @@ __logbf (float x)
   GET_FLOAT_WORD (ix, x);
   ix &= 0x7fffffff;		/* high |x| */
   if (ix == 0)
-    return (float) -1.0 / fabsf (x);
+    /* Pole error: logbf (+-0).  */
+    return __math_divzerof (1);
   if (ix >= 0x7f800000)
     return x * x;
   if (__glibc_unlikely ((rix = ix >> 23) == 0))
diff --git a/sysdeps/ieee754/ldbl-128/s_logbl.c b/sysdeps/ieee754/ldbl-128/s_logbl.c
index 7927155cac..2151a04117 100644
--- a/sysdeps/ieee754/ldbl-128/s_logbl.c
+++ b/sysdeps/ieee754/ldbl-128/s_logbl.c
@@ -23,6 +23,8 @@ static char rcsid[] = "$NetBSD: $";
  */
 
 #include <math.h>
+#include <errno.h>
+#include <math-barriers.h>
 #include <math_private.h>
 #include <libm-alias-ldouble.h>
 
@@ -30,6 +32,12 @@ _Float128
 __logbl (_Float128 x)
 {
 #if USE_LOGBL_BUILTIN
+  if (__glibc_unlikely (x == 0))
+    {
+      /* Pole error: logbl (+-0).  */
+      __set_errno (ERANGE);
+      return math_opt_barrier (-1.0) / fabsl (x);
+    }
   return __builtin_logbl (x);
 #else
   /* Use generic implementation.  */
@@ -38,7 +46,11 @@ __logbl (_Float128 x)
   GET_LDOUBLE_WORDS64 (hx, lx, x);
   hx &= 0x7fffffffffffffffLL;	/* high |x| */
   if ((hx | lx) == 0)
-    return -1.0 / fabsl (x);
+    {
+      /* Pole error: logbl (+-0).  */
+      __set_errno (ERANGE);
+      return math_opt_barrier (-1.0) / fabsl (x);
+    }
   if (hx >= 0x7fff000000000000LL)
     return x * x;
   if ((ex = hx >> 48) == 0)	/* IEEE 754 logb */
diff --git a/sysdeps/ieee754/ldbl-128ibm/s_logbl.c b/sysdeps/ieee754/ldbl-128ibm/s_logbl.c
index 37ef47b6a4..cea7c14d8b 100644
--- a/sysdeps/ieee754/ldbl-128ibm/s_logbl.c
+++ b/sysdeps/ieee754/ldbl-128ibm/s_logbl.c
@@ -19,6 +19,8 @@
  */
 
 #include <math.h>
+#include <errno.h>
+#include <math-barriers.h>
 #include <math_private.h>
 #include <math_ldbl_opt.h>
 #include <fix-int-fp-convert-zero.h>
@@ -34,7 +36,11 @@ __logbl (long double x)
   hxs = hx;
   hx &= 0x7fffffffffffffffLL;	/* high |x| */
   if (hx == 0)
-    return -1.0 / fabs (x);
+    {
+      /* Pole error: logbl (+-0).  */
+      __set_errno (ERANGE);
+      return math_opt_barrier (-1.0) / fabs (x);
+    }
   if (hx >= 0x7ff0000000000000LL)
     return x * x;
   if (__glibc_unlikely ((rhx = hx >> 52) == 0))
diff --git a/sysdeps/m68k/m680x0/fpu/s_logbl.c b/sysdeps/m68k/m680x0/fpu/s_logbl.c
index 8cd2326bf8..ec2448aebe 100644
--- a/sysdeps/m68k/m680x0/fpu/s_logbl.c
+++ b/sysdeps/m68k/m680x0/fpu/s_logbl.c
@@ -19,6 +19,8 @@
  */
 
 #include <math.h>
+#include <errno.h>
+#include <math-barriers.h>
 #include <math_private.h>
 
 long double
@@ -29,7 +31,11 @@ __logbl (long double x)
   GET_LDOUBLE_WORDS (es, ix, lx, x);
   es &= 0x7fff;			/* exponent */
   if ((es | ix | lx) == 0)
-    return -1.0 / fabsl (x);
+    {
+      /* Pole error: logbl (+-0).  */
+      __set_errno (ERANGE);
+      return math_opt_barrier (-1.0) / fabsl (x);
+    }
   if (es == 0x7fff)
     return x * x;
   if (es == 0)			/* IEEE 754 logb */
diff --git a/sysdeps/powerpc/fpu/s_logb.c b/sysdeps/powerpc/fpu/s_logb.c
index 880e48e0f5..bcda752bed 100644
--- a/sysdeps/powerpc/fpu/s_logb.c
+++ b/sysdeps/powerpc/fpu/s_logb.c
@@ -22,6 +22,8 @@
 # include <sysdeps/ieee754/dbl-64/s_logb.c>
 #else
 # include <math.h>
+# include <errno.h>
+# include <math-barriers.h>
 # include <math_private.h>
 # include <math_ldbl_opt.h>
 # include <libm-alias-double.h>
@@ -34,8 +36,11 @@ __logb (double x)
   double ret;
 
   if (__glibc_unlikely (x == 0.0))
-    /* Raise FE_DIVBYZERO and return -HUGE_VAL[LF].  */
-    return -1.0 / fabs (x);
+    {
+      /* Pole error: raise FE_DIVBYZERO, set errno and return -HUGE_VAL.  */
+      __set_errno (ERANGE);
+      return math_opt_barrier (-1.0) / fabs (x);
+    }
 
   /* Mask to extract the exponent.  */
   asm ("xxland %x0,%x1,%x2\n"
diff --git a/sysdeps/powerpc/fpu/s_logbf.c b/sysdeps/powerpc/fpu/s_logbf.c
index c640aa88bc..beeecf9c20 100644
--- a/sysdeps/powerpc/fpu/s_logbf.c
+++ b/sysdeps/powerpc/fpu/s_logbf.c
@@ -22,6 +22,8 @@
 # include <sysdeps/ieee754/flt-32/s_logbf.c>
 #else
 # include <math.h>
+# include <errno.h>
+# include <math-barriers.h>
 # include <libm-alias-float.h>
 /* This implementation avoids FP to INT conversions by using VSX
    bitwise instructions over FP values.  */
@@ -32,8 +34,11 @@ __logbf (float x)
   double ret;
 
   if (__glibc_unlikely (x == 0.0))
-    /* Raise FE_DIVBYZERO and return -HUGE_VAL[LF].  */
-    return -1.0 / fabs (x);
+    {
+      /* Pole error: raise FE_DIVBYZERO, set errno and return -HUGE_VALF.  */
+      __set_errno (ERANGE);
+      return math_opt_barrier (-1.0) / fabs (x);
+    }
 
   /* mask to extract the exponent.  */
   asm ("xxland %x0,%x1,%x2\n"
diff --git a/sysdeps/powerpc/fpu/s_logbl.c b/sysdeps/powerpc/fpu/s_logbl.c
index 51edd8ebde..4111fb221c 100644
--- a/sysdeps/powerpc/fpu/s_logbl.c
+++ b/sysdeps/powerpc/fpu/s_logbl.c
@@ -22,6 +22,8 @@
 # include <./sysdeps/ieee754/ldbl-128ibm/s_logbl.c>
 #else
 # include <math.h>
+# include <errno.h>
+# include <math-barriers.h>
 # include <math_private.h>
 # include <math_ldbl_opt.h>
 
@@ -35,8 +37,11 @@ __logbl (long double x)
   int64_t hx;
 
   if (__glibc_unlikely (x == 0.0))
-    /* Raise FE_DIVBYZERO and return -HUGE_VAL[LF].  */
-    return -1.0L / __builtin_fabsl (x);
+    {
+      /* Pole error: raise FE_DIVBYZERO, set errno and return -HUGE_VALL.  */
+      __set_errno (ERANGE);
+      return math_opt_barrier (-1.0L) / __builtin_fabsl (x);
+    }
 
   ldbl_unpack (x, &xh, &xl);
   EXTRACT_WORDS64 (hx, xh);
diff --git a/sysdeps/i386/fpu/s_logbl.c b/sysdeps/x86/fpu/s_logbl.c
similarity index 50%
rename from sysdeps/i386/fpu/s_logbl.c
rename to sysdeps/x86/fpu/s_logbl.c
index ec867de010..91056e1b06 100644
--- a/sysdeps/i386/fpu/s_logbl.c
+++ b/sysdeps/x86/fpu/s_logbl.c
@@ -2,6 +2,9 @@
  * Public domain.
  */
 
+#include <math.h>
+#include <errno.h>
+#include <math-barriers.h>
 #include <libm-alias-ldouble.h>
 
 long double
@@ -9,6 +12,13 @@ __logbl (long double x)
 {
   long double res;
 
+  if (__glibc_unlikely (x == 0))
+    {
+      /* Pole error: logbl (+-0).  */
+      __set_errno (ERANGE);
+      return math_opt_barrier (-1.0L) / 0.0L;
+    }
+
   asm ("fxtract\n"
        "fstp	%%st" : "=t" (res) : "0" (x));
   return res;
diff --git a/sysdeps/x86_64/fpu/s_logbl.c b/sysdeps/x86_64/fpu/s_logbl.c
deleted file mode 100644
index 4791ba64e8..0000000000
--- a/sysdeps/x86_64/fpu/s_logbl.c
+++ /dev/null
@@ -1 +0,0 @@
-#include <sysdeps/i386/fpu/s_logbl.c>