From: Joseph Myers <joseph@codesourcery.com>
Date: Thu, 14 May 2015 23:38:07 +0000 (+0000)
Subject: Fix log1p missing underflows (bug 16339).
X-Git-Tag: glibc-2.22~323
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=0b7a5f920163d03806d7c5d9d1c83b16942c9496;p=thirdparty%2Fglibc.git

Fix log1p missing underflows (bug 16339).

Similar to various other bugs in this area, some log1p implementations
do not raise the underflow exception for subnormal arguments, when the
result is tiny and inexact.  This patch forces the exception in a
similar way to previous fixes.  (The ldbl-128ibm implementation
doesn't currently need any change as it already generates this
exception, albeit through code that would generate spurious exceptions
in other cases; special code for this issue will only be needed there
when fixing the spurious exceptions.)

Tested for x86_64, x86, powerpc and mips64.

	[BZ #16339]
	* sysdeps/i386/fpu/s_log1p.S (dbl_min): New object.
	(__log1p): Force underflow exception for results with small
	absolute value.
	* sysdeps/i386/fpu/s_log1pf.S (flt_min): New object.
	(__log1pf): Force underflow exception for results with small
	absolute value.
	* sysdeps/ieee754/dbl-64/s_log1p.c: Include <float.h>.
	(__log1p): Force underflow exception for results with small
	absolute value.
	* sysdeps/ieee754/flt-32/s_log1pf.c: Include <float.h>.
	(__log1pf): Force underflow exception for results with small
	absolute value.
	* sysdeps/ieee754/ldbl-128/s_log1pl.c: Include <float.h>.
	(__log1pl): Force underflow exception for results with small
	absolute value.
	* math/auto-libm-test-in: Do not allow missing underflow
	exceptions from log1p.
	* math/auto-libm-test-out: Regenerated.
---

diff --git a/ChangeLog b/ChangeLog
index 3f3a5b14e7f..f6bf877b167 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,25 @@
+2015-05-14  Joseph Myers  <joseph@codesourcery.com>
+
+	[BZ #16339]
+	* sysdeps/i386/fpu/s_log1p.S (dbl_min): New object.
+	(__log1p): Force underflow exception for results with small
+	absolute value.
+	* sysdeps/i386/fpu/s_log1pf.S (flt_min): New object.
+	(__log1pf): Force underflow exception for results with small
+	absolute value.
+	* sysdeps/ieee754/dbl-64/s_log1p.c: Include <float.h>.
+	(__log1p): Force underflow exception for results with small
+	absolute value.
+	* sysdeps/ieee754/flt-32/s_log1pf.c: Include <float.h>.
+	(__log1pf): Force underflow exception for results with small
+	absolute value.
+	* sysdeps/ieee754/ldbl-128/s_log1pl.c: Include <float.h>.
+	(__log1pl): Force underflow exception for results with small
+	absolute value.
+	* math/auto-libm-test-in: Do not allow missing underflow
+	exceptions from log1p.
+	* math/auto-libm-test-out: Regenerated.
+
 2015-05-14  Jakub Bogusz  <qboosh@pld-linux.org>
 	    Adhemerval Zanella  <adhemerval.zanella@linaro.org>
 
diff --git a/NEWS b/NEWS
index 91027bd83b6..a9b0138b3e8 100644
--- a/NEWS
+++ b/NEWS
@@ -9,7 +9,7 @@ Version 2.22
 
 * The following bugs are resolved with this release:
 
-  4719, 6792, 13064, 14094, 14841, 14906, 15319, 15467, 15790, 15969,
+  4719, 6792, 13064, 14094, 14841, 14906, 15319, 15467, 15790, 15969, 16339,
   16351, 16512, 16560, 16783, 16850, 17090, 17195, 17269, 17523, 17542,
   17569, 17588, 17596, 17620, 17621, 17628, 17631, 17692, 17711, 17715,
   17776, 17779, 17792, 17836, 17912, 17916, 17930, 17932, 17944, 17949,
diff --git a/math/auto-libm-test-in b/math/auto-libm-test-in
index 883397c40ad..7e5c7bb254f 100644
--- a/math/auto-libm-test-in
+++ b/math/auto-libm-test-in
@@ -1850,11 +1850,10 @@ log1p -0
 log1p e-1
 log1p -0.25
 log1p -0.875
-# Bug 16339: underflow exception may be missing.
-log1p min missing-underflow
-log1p min_subnorm missing-underflow
-log1p -min missing-underflow
-log1p -min_subnorm missing-underflow
+log1p min
+log1p min_subnorm
+log1p -min
+log1p -min_subnorm
 log1p 0x1p10
 log1p 0x1p20
 log1p 0x1p30
diff --git a/math/auto-libm-test-out b/math/auto-libm-test-out
index 0d7fac54d6d..7c8a3fb8fff 100644
--- a/math/auto-libm-test-out
+++ b/math/auto-libm-test-out
@@ -143235,7 +143235,7 @@ log1p -0.875
 = log1p tonearest ldbl-128ibm -0xep-4L : -0x2.145647e7756e6d035dab1ac80cp+0L : inexact-ok
 = log1p towardzero ldbl-128ibm -0xep-4L : -0x2.145647e7756e6d035dab1ac80bp+0L : inexact-ok
 = log1p upward ldbl-128ibm -0xep-4L : -0x2.145647e7756e6d035dab1ac80bp+0L : inexact-ok
-log1p min missing-underflow
+log1p min
 = log1p downward flt-32 0x4p-128f : 0x3.fffff8p-128f : inexact-ok underflow-ok errno-erange-ok
 = log1p tonearest flt-32 0x4p-128f : 0x4p-128f : inexact-ok underflow-ok errno-erange-ok
 = log1p towardzero flt-32 0x4p-128f : 0x3.fffff8p-128f : inexact-ok underflow-ok errno-erange-ok
@@ -143276,10 +143276,10 @@ log1p min missing-underflow
 = log1p tonearest ldbl-128 0x4p-1024L : 0x4p-1024L : inexact-ok
 = log1p towardzero ldbl-128 0x4p-1024L : 0x3.fffffffffffffffffffffffffffep-1024L : inexact-ok
 = log1p upward ldbl-128 0x4p-1024L : 0x4p-1024L : inexact-ok
-= log1p downward ldbl-128ibm 0x4p-1024L : 0x3.ffffffffffffcp-1024L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p tonearest ldbl-128ibm 0x4p-1024L : 0x4p-1024L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p towardzero ldbl-128ibm 0x4p-1024L : 0x3.ffffffffffffcp-1024L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p upward ldbl-128ibm 0x4p-1024L : 0x4p-1024L : inexact-ok underflow underflow-ok errno-erange-ok
+= log1p downward ldbl-128ibm 0x4p-1024L : 0x3.ffffffffffffcp-1024L : inexact-ok underflow errno-erange-ok
+= log1p tonearest ldbl-128ibm 0x4p-1024L : 0x4p-1024L : inexact-ok underflow errno-erange-ok
+= log1p towardzero ldbl-128ibm 0x4p-1024L : 0x3.ffffffffffffcp-1024L : inexact-ok underflow errno-erange-ok
+= log1p upward ldbl-128ibm 0x4p-1024L : 0x4p-1024L : inexact-ok underflow errno-erange-ok
 = log1p downward ldbl-96-intel 0x4p-16384L : 0x3.fffffffffffffff8p-16384L : inexact-ok underflow-ok errno-erange-ok
 = log1p tonearest ldbl-96-intel 0x4p-16384L : 0x4p-16384L : inexact-ok underflow-ok errno-erange-ok
 = log1p towardzero ldbl-96-intel 0x4p-16384L : 0x3.fffffffffffffff8p-16384L : inexact-ok underflow-ok errno-erange-ok
@@ -143292,18 +143292,18 @@ log1p min missing-underflow
 = log1p tonearest ldbl-128 0x4p-16384L : 0x4p-16384L : inexact-ok underflow-ok errno-erange-ok
 = log1p towardzero ldbl-128 0x4p-16384L : 0x3.fffffffffffffffffffffffffffcp-16384L : inexact-ok underflow-ok errno-erange-ok
 = log1p upward ldbl-128 0x4p-16384L : 0x4p-16384L : inexact-ok underflow-ok errno-erange-ok
-= log1p downward ldbl-96-intel 0x2p-16384L : 0x1.fffffffffffffff8p-16384L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p tonearest ldbl-96-intel 0x2p-16384L : 0x2p-16384L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p towardzero ldbl-96-intel 0x2p-16384L : 0x1.fffffffffffffff8p-16384L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p upward ldbl-96-intel 0x2p-16384L : 0x2p-16384L : inexact-ok underflow underflow-ok errno-erange-ok
+= log1p downward ldbl-96-intel 0x2p-16384L : 0x1.fffffffffffffff8p-16384L : inexact-ok underflow errno-erange-ok
+= log1p tonearest ldbl-96-intel 0x2p-16384L : 0x2p-16384L : inexact-ok underflow errno-erange-ok
+= log1p towardzero ldbl-96-intel 0x2p-16384L : 0x1.fffffffffffffff8p-16384L : inexact-ok underflow errno-erange-ok
+= log1p upward ldbl-96-intel 0x2p-16384L : 0x2p-16384L : inexact-ok underflow errno-erange-ok
 = log1p downward ldbl-96-m68k 0x2p-16384L : 0x1.fffffffffffffffcp-16384L : inexact-ok underflow-ok errno-erange-ok
 = log1p tonearest ldbl-96-m68k 0x2p-16384L : 0x2p-16384L : inexact-ok underflow-ok errno-erange-ok
 = log1p towardzero ldbl-96-m68k 0x2p-16384L : 0x1.fffffffffffffffcp-16384L : inexact-ok underflow-ok errno-erange-ok
 = log1p upward ldbl-96-m68k 0x2p-16384L : 0x2p-16384L : inexact-ok underflow-ok errno-erange-ok
-= log1p downward ldbl-128 0x2p-16384L : 0x1.fffffffffffffffffffffffffffcp-16384L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p tonearest ldbl-128 0x2p-16384L : 0x2p-16384L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p towardzero ldbl-128 0x2p-16384L : 0x1.fffffffffffffffffffffffffffcp-16384L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p upward ldbl-128 0x2p-16384L : 0x2p-16384L : inexact-ok underflow underflow-ok errno-erange-ok
+= log1p downward ldbl-128 0x2p-16384L : 0x1.fffffffffffffffffffffffffffcp-16384L : inexact-ok underflow errno-erange-ok
+= log1p tonearest ldbl-128 0x2p-16384L : 0x2p-16384L : inexact-ok underflow errno-erange-ok
+= log1p towardzero ldbl-128 0x2p-16384L : 0x1.fffffffffffffffffffffffffffcp-16384L : inexact-ok underflow errno-erange-ok
+= log1p upward ldbl-128 0x2p-16384L : 0x2p-16384L : inexact-ok underflow errno-erange-ok
 = log1p downward dbl-64 0x8p-972 : 0x7.ffffffffffffcp-972 : inexact-ok
 = log1p tonearest dbl-64 0x8p-972 : 0x8p-972 : inexact-ok
 = log1p towardzero dbl-64 0x8p-972 : 0x7.ffffffffffffcp-972 : inexact-ok
@@ -143324,11 +143324,11 @@ log1p min missing-underflow
 = log1p tonearest ldbl-128ibm 0x8p-972L : 0x8p-972L : inexact-ok underflow-ok errno-erange-ok
 = log1p towardzero ldbl-128ibm 0x8p-972L : 0x7.fffffffffffffffffffffffffcp-972L : inexact-ok underflow-ok errno-erange-ok
 = log1p upward ldbl-128ibm 0x8p-972L : 0x8p-972L : inexact-ok underflow-ok errno-erange-ok
-log1p min_subnorm missing-underflow
-= log1p downward flt-32 0x8p-152f : 0x0p+0f : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p tonearest flt-32 0x8p-152f : 0x8p-152f : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p towardzero flt-32 0x8p-152f : 0x0p+0f : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p upward flt-32 0x8p-152f : 0x8p-152f : inexact-ok underflow underflow-ok errno-erange-ok
+log1p min_subnorm
+= log1p downward flt-32 0x8p-152f : 0x0p+0f : inexact-ok underflow errno-erange-ok
+= log1p tonearest flt-32 0x8p-152f : 0x8p-152f : inexact-ok underflow errno-erange-ok
+= log1p towardzero flt-32 0x8p-152f : 0x0p+0f : inexact-ok underflow errno-erange-ok
+= log1p upward flt-32 0x8p-152f : 0x8p-152f : inexact-ok underflow errno-erange-ok
 = log1p downward dbl-64 0x8p-152 : 0x7.ffffffffffffcp-152 : inexact-ok
 = log1p tonearest dbl-64 0x8p-152 : 0x8p-152 : inexact-ok
 = log1p towardzero dbl-64 0x8p-152 : 0x7.ffffffffffffcp-152 : inexact-ok
@@ -143349,10 +143349,10 @@ log1p min_subnorm missing-underflow
 = log1p tonearest ldbl-128ibm 0x8p-152L : 0x8p-152L : inexact-ok
 = log1p towardzero ldbl-128ibm 0x8p-152L : 0x7.fffffffffffffffffffffffffep-152L : inexact-ok
 = log1p upward ldbl-128ibm 0x8p-152L : 0x8p-152L : inexact-ok
-= log1p downward dbl-64 0x4p-1076 : 0x0p+0 : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p tonearest dbl-64 0x4p-1076 : 0x4p-1076 : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p towardzero dbl-64 0x4p-1076 : 0x0p+0 : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p upward dbl-64 0x4p-1076 : 0x4p-1076 : inexact-ok underflow underflow-ok errno-erange-ok
+= log1p downward dbl-64 0x4p-1076 : 0x0p+0 : inexact-ok underflow errno-erange-ok
+= log1p tonearest dbl-64 0x4p-1076 : 0x4p-1076 : inexact-ok underflow errno-erange-ok
+= log1p towardzero dbl-64 0x4p-1076 : 0x0p+0 : inexact-ok underflow errno-erange-ok
+= log1p upward dbl-64 0x4p-1076 : 0x4p-1076 : inexact-ok underflow errno-erange-ok
 = log1p downward ldbl-96-intel 0x4p-1076L : 0x3.fffffffffffffffcp-1076L : inexact-ok
 = log1p tonearest ldbl-96-intel 0x4p-1076L : 0x4p-1076L : inexact-ok
 = log1p towardzero ldbl-96-intel 0x4p-1076L : 0x3.fffffffffffffffcp-1076L : inexact-ok
@@ -143365,35 +143365,35 @@ log1p min_subnorm missing-underflow
 = log1p tonearest ldbl-128 0x4p-1076L : 0x4p-1076L : inexact-ok
 = log1p towardzero ldbl-128 0x4p-1076L : 0x3.fffffffffffffffffffffffffffep-1076L : inexact-ok
 = log1p upward ldbl-128 0x4p-1076L : 0x4p-1076L : inexact-ok
-= log1p downward ldbl-128ibm 0x4p-1076L : 0x0p+0L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p tonearest ldbl-128ibm 0x4p-1076L : 0x4p-1076L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p towardzero ldbl-128ibm 0x4p-1076L : 0x0p+0L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p upward ldbl-128ibm 0x4p-1076L : 0x4p-1076L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p downward ldbl-96-intel 0x8p-16448L : 0x0p+0L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p tonearest ldbl-96-intel 0x8p-16448L : 0x8p-16448L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p towardzero ldbl-96-intel 0x8p-16448L : 0x0p+0L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p upward ldbl-96-intel 0x8p-16448L : 0x8p-16448L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p downward ldbl-96-m68k 0x8p-16448L : 0x4p-16448L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p tonearest ldbl-96-m68k 0x8p-16448L : 0x8p-16448L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p towardzero ldbl-96-m68k 0x8p-16448L : 0x4p-16448L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p upward ldbl-96-m68k 0x8p-16448L : 0x8p-16448L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p downward ldbl-128 0x8p-16448L : 0x7.fffffffffffcp-16448L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p tonearest ldbl-128 0x8p-16448L : 0x8p-16448L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p towardzero ldbl-128 0x8p-16448L : 0x7.fffffffffffcp-16448L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p upward ldbl-128 0x8p-16448L : 0x8p-16448L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p downward ldbl-96-m68k 0x4p-16448L : 0x0p+0L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p tonearest ldbl-96-m68k 0x4p-16448L : 0x4p-16448L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p towardzero ldbl-96-m68k 0x4p-16448L : 0x0p+0L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p upward ldbl-96-m68k 0x4p-16448L : 0x4p-16448L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p downward ldbl-128 0x4p-16448L : 0x3.fffffffffffcp-16448L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p tonearest ldbl-128 0x4p-16448L : 0x4p-16448L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p towardzero ldbl-128 0x4p-16448L : 0x3.fffffffffffcp-16448L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p upward ldbl-128 0x4p-16448L : 0x4p-16448L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p downward ldbl-128 0x4p-16496L : 0x0p+0L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p tonearest ldbl-128 0x4p-16496L : 0x4p-16496L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p towardzero ldbl-128 0x4p-16496L : 0x0p+0L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p upward ldbl-128 0x4p-16496L : 0x4p-16496L : inexact-ok underflow underflow-ok errno-erange-ok
-log1p -min missing-underflow
+= log1p downward ldbl-128ibm 0x4p-1076L : 0x0p+0L : inexact-ok underflow errno-erange-ok
+= log1p tonearest ldbl-128ibm 0x4p-1076L : 0x4p-1076L : inexact-ok underflow errno-erange-ok
+= log1p towardzero ldbl-128ibm 0x4p-1076L : 0x0p+0L : inexact-ok underflow errno-erange-ok
+= log1p upward ldbl-128ibm 0x4p-1076L : 0x4p-1076L : inexact-ok underflow errno-erange-ok
+= log1p downward ldbl-96-intel 0x8p-16448L : 0x0p+0L : inexact-ok underflow errno-erange-ok
+= log1p tonearest ldbl-96-intel 0x8p-16448L : 0x8p-16448L : inexact-ok underflow errno-erange-ok
+= log1p towardzero ldbl-96-intel 0x8p-16448L : 0x0p+0L : inexact-ok underflow errno-erange-ok
+= log1p upward ldbl-96-intel 0x8p-16448L : 0x8p-16448L : inexact-ok underflow errno-erange-ok
+= log1p downward ldbl-96-m68k 0x8p-16448L : 0x4p-16448L : inexact-ok underflow errno-erange-ok
+= log1p tonearest ldbl-96-m68k 0x8p-16448L : 0x8p-16448L : inexact-ok underflow errno-erange-ok
+= log1p towardzero ldbl-96-m68k 0x8p-16448L : 0x4p-16448L : inexact-ok underflow errno-erange-ok
+= log1p upward ldbl-96-m68k 0x8p-16448L : 0x8p-16448L : inexact-ok underflow errno-erange-ok
+= log1p downward ldbl-128 0x8p-16448L : 0x7.fffffffffffcp-16448L : inexact-ok underflow errno-erange-ok
+= log1p tonearest ldbl-128 0x8p-16448L : 0x8p-16448L : inexact-ok underflow errno-erange-ok
+= log1p towardzero ldbl-128 0x8p-16448L : 0x7.fffffffffffcp-16448L : inexact-ok underflow errno-erange-ok
+= log1p upward ldbl-128 0x8p-16448L : 0x8p-16448L : inexact-ok underflow errno-erange-ok
+= log1p downward ldbl-96-m68k 0x4p-16448L : 0x0p+0L : inexact-ok underflow errno-erange-ok
+= log1p tonearest ldbl-96-m68k 0x4p-16448L : 0x4p-16448L : inexact-ok underflow errno-erange-ok
+= log1p towardzero ldbl-96-m68k 0x4p-16448L : 0x0p+0L : inexact-ok underflow errno-erange-ok
+= log1p upward ldbl-96-m68k 0x4p-16448L : 0x4p-16448L : inexact-ok underflow errno-erange-ok
+= log1p downward ldbl-128 0x4p-16448L : 0x3.fffffffffffcp-16448L : inexact-ok underflow errno-erange-ok
+= log1p tonearest ldbl-128 0x4p-16448L : 0x4p-16448L : inexact-ok underflow errno-erange-ok
+= log1p towardzero ldbl-128 0x4p-16448L : 0x3.fffffffffffcp-16448L : inexact-ok underflow errno-erange-ok
+= log1p upward ldbl-128 0x4p-16448L : 0x4p-16448L : inexact-ok underflow errno-erange-ok
+= log1p downward ldbl-128 0x4p-16496L : 0x0p+0L : inexact-ok underflow errno-erange-ok
+= log1p tonearest ldbl-128 0x4p-16496L : 0x4p-16496L : inexact-ok underflow errno-erange-ok
+= log1p towardzero ldbl-128 0x4p-16496L : 0x0p+0L : inexact-ok underflow errno-erange-ok
+= log1p upward ldbl-128 0x4p-16496L : 0x4p-16496L : inexact-ok underflow errno-erange-ok
+log1p -min
 = log1p downward flt-32 -0x4p-128f : -0x4.000008p-128f : inexact-ok underflow-ok errno-erange-ok
 = log1p tonearest flt-32 -0x4p-128f : -0x4p-128f : inexact-ok underflow-ok errno-erange-ok
 = log1p towardzero flt-32 -0x4p-128f : -0x4p-128f : inexact-ok underflow-ok errno-erange-ok
@@ -143434,10 +143434,10 @@ log1p -min missing-underflow
 = log1p tonearest ldbl-128 -0x4p-1024L : -0x4p-1024L : inexact-ok
 = log1p towardzero ldbl-128 -0x4p-1024L : -0x4p-1024L : inexact-ok
 = log1p upward ldbl-128 -0x4p-1024L : -0x4p-1024L : inexact-ok
-= log1p downward ldbl-128ibm -0x4p-1024L : -0x4.0000000000004p-1024L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p tonearest ldbl-128ibm -0x4p-1024L : -0x4p-1024L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p towardzero ldbl-128ibm -0x4p-1024L : -0x4p-1024L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p upward ldbl-128ibm -0x4p-1024L : -0x4p-1024L : inexact-ok underflow underflow-ok errno-erange-ok
+= log1p downward ldbl-128ibm -0x4p-1024L : -0x4.0000000000004p-1024L : inexact-ok underflow errno-erange-ok
+= log1p tonearest ldbl-128ibm -0x4p-1024L : -0x4p-1024L : inexact-ok underflow errno-erange-ok
+= log1p towardzero ldbl-128ibm -0x4p-1024L : -0x4p-1024L : inexact-ok underflow errno-erange-ok
+= log1p upward ldbl-128ibm -0x4p-1024L : -0x4p-1024L : inexact-ok underflow errno-erange-ok
 = log1p downward ldbl-96-intel -0x4p-16384L : -0x4.0000000000000008p-16384L : inexact-ok underflow-ok errno-erange-ok
 = log1p tonearest ldbl-96-intel -0x4p-16384L : -0x4p-16384L : inexact-ok underflow-ok errno-erange-ok
 = log1p towardzero ldbl-96-intel -0x4p-16384L : -0x4p-16384L : inexact-ok underflow-ok errno-erange-ok
@@ -143450,18 +143450,18 @@ log1p -min missing-underflow
 = log1p tonearest ldbl-128 -0x4p-16384L : -0x4p-16384L : inexact-ok underflow-ok errno-erange-ok
 = log1p towardzero ldbl-128 -0x4p-16384L : -0x4p-16384L : inexact-ok underflow-ok errno-erange-ok
 = log1p upward ldbl-128 -0x4p-16384L : -0x4p-16384L : inexact-ok underflow-ok errno-erange-ok
-= log1p downward ldbl-96-intel -0x2p-16384L : -0x2.0000000000000008p-16384L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p tonearest ldbl-96-intel -0x2p-16384L : -0x2p-16384L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p towardzero ldbl-96-intel -0x2p-16384L : -0x2p-16384L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p upward ldbl-96-intel -0x2p-16384L : -0x2p-16384L : inexact-ok underflow underflow-ok errno-erange-ok
+= log1p downward ldbl-96-intel -0x2p-16384L : -0x2.0000000000000008p-16384L : inexact-ok underflow errno-erange-ok
+= log1p tonearest ldbl-96-intel -0x2p-16384L : -0x2p-16384L : inexact-ok underflow errno-erange-ok
+= log1p towardzero ldbl-96-intel -0x2p-16384L : -0x2p-16384L : inexact-ok underflow errno-erange-ok
+= log1p upward ldbl-96-intel -0x2p-16384L : -0x2p-16384L : inexact-ok underflow errno-erange-ok
 = log1p downward ldbl-96-m68k -0x2p-16384L : -0x2.0000000000000004p-16384L : inexact-ok underflow-ok errno-erange-ok
 = log1p tonearest ldbl-96-m68k -0x2p-16384L : -0x2p-16384L : inexact-ok underflow-ok errno-erange-ok
 = log1p towardzero ldbl-96-m68k -0x2p-16384L : -0x2p-16384L : inexact-ok underflow-ok errno-erange-ok
 = log1p upward ldbl-96-m68k -0x2p-16384L : -0x2p-16384L : inexact-ok underflow-ok errno-erange-ok
-= log1p downward ldbl-128 -0x2p-16384L : -0x2.0000000000000000000000000004p-16384L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p tonearest ldbl-128 -0x2p-16384L : -0x2p-16384L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p towardzero ldbl-128 -0x2p-16384L : -0x2p-16384L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p upward ldbl-128 -0x2p-16384L : -0x2p-16384L : inexact-ok underflow underflow-ok errno-erange-ok
+= log1p downward ldbl-128 -0x2p-16384L : -0x2.0000000000000000000000000004p-16384L : inexact-ok underflow errno-erange-ok
+= log1p tonearest ldbl-128 -0x2p-16384L : -0x2p-16384L : inexact-ok underflow errno-erange-ok
+= log1p towardzero ldbl-128 -0x2p-16384L : -0x2p-16384L : inexact-ok underflow errno-erange-ok
+= log1p upward ldbl-128 -0x2p-16384L : -0x2p-16384L : inexact-ok underflow errno-erange-ok
 = log1p downward dbl-64 -0x8p-972 : -0x8.0000000000008p-972 : inexact-ok
 = log1p tonearest dbl-64 -0x8p-972 : -0x8p-972 : inexact-ok
 = log1p towardzero dbl-64 -0x8p-972 : -0x8p-972 : inexact-ok
@@ -143482,11 +143482,11 @@ log1p -min missing-underflow
 = log1p tonearest ldbl-128ibm -0x8p-972L : -0x8p-972L : inexact-ok underflow-ok errno-erange-ok
 = log1p towardzero ldbl-128ibm -0x8p-972L : -0x8p-972L : inexact-ok underflow-ok errno-erange-ok
 = log1p upward ldbl-128ibm -0x8p-972L : -0x8p-972L : inexact-ok underflow-ok errno-erange-ok
-log1p -min_subnorm missing-underflow
-= log1p downward flt-32 -0x8p-152f : -0x1p-148f : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p tonearest flt-32 -0x8p-152f : -0x8p-152f : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p towardzero flt-32 -0x8p-152f : -0x8p-152f : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p upward flt-32 -0x8p-152f : -0x8p-152f : inexact-ok underflow underflow-ok errno-erange-ok
+log1p -min_subnorm
+= log1p downward flt-32 -0x8p-152f : -0x1p-148f : inexact-ok underflow errno-erange-ok
+= log1p tonearest flt-32 -0x8p-152f : -0x8p-152f : inexact-ok underflow errno-erange-ok
+= log1p towardzero flt-32 -0x8p-152f : -0x8p-152f : inexact-ok underflow errno-erange-ok
+= log1p upward flt-32 -0x8p-152f : -0x8p-152f : inexact-ok underflow errno-erange-ok
 = log1p downward dbl-64 -0x8p-152 : -0x8.0000000000008p-152 : inexact-ok
 = log1p tonearest dbl-64 -0x8p-152 : -0x8p-152 : inexact-ok
 = log1p towardzero dbl-64 -0x8p-152 : -0x8p-152 : inexact-ok
@@ -143507,10 +143507,10 @@ log1p -min_subnorm missing-underflow
 = log1p tonearest ldbl-128ibm -0x8p-152L : -0x8p-152L : inexact-ok
 = log1p towardzero ldbl-128ibm -0x8p-152L : -0x8p-152L : inexact-ok
 = log1p upward ldbl-128ibm -0x8p-152L : -0x8p-152L : inexact-ok
-= log1p downward dbl-64 -0x4p-1076 : -0x8p-1076 : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p tonearest dbl-64 -0x4p-1076 : -0x4p-1076 : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p towardzero dbl-64 -0x4p-1076 : -0x4p-1076 : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p upward dbl-64 -0x4p-1076 : -0x4p-1076 : inexact-ok underflow underflow-ok errno-erange-ok
+= log1p downward dbl-64 -0x4p-1076 : -0x8p-1076 : inexact-ok underflow errno-erange-ok
+= log1p tonearest dbl-64 -0x4p-1076 : -0x4p-1076 : inexact-ok underflow errno-erange-ok
+= log1p towardzero dbl-64 -0x4p-1076 : -0x4p-1076 : inexact-ok underflow errno-erange-ok
+= log1p upward dbl-64 -0x4p-1076 : -0x4p-1076 : inexact-ok underflow errno-erange-ok
 = log1p downward ldbl-96-intel -0x4p-1076L : -0x4.0000000000000008p-1076L : inexact-ok
 = log1p tonearest ldbl-96-intel -0x4p-1076L : -0x4p-1076L : inexact-ok
 = log1p towardzero ldbl-96-intel -0x4p-1076L : -0x4p-1076L : inexact-ok
@@ -143523,34 +143523,34 @@ log1p -min_subnorm missing-underflow
 = log1p tonearest ldbl-128 -0x4p-1076L : -0x4p-1076L : inexact-ok
 = log1p towardzero ldbl-128 -0x4p-1076L : -0x4p-1076L : inexact-ok
 = log1p upward ldbl-128 -0x4p-1076L : -0x4p-1076L : inexact-ok
-= log1p downward ldbl-128ibm -0x4p-1076L : -0x8p-1076L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p tonearest ldbl-128ibm -0x4p-1076L : -0x4p-1076L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p towardzero ldbl-128ibm -0x4p-1076L : -0x4p-1076L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p upward ldbl-128ibm -0x4p-1076L : -0x4p-1076L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p downward ldbl-96-intel -0x8p-16448L : -0x1p-16444L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p tonearest ldbl-96-intel -0x8p-16448L : -0x8p-16448L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p towardzero ldbl-96-intel -0x8p-16448L : -0x8p-16448L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p upward ldbl-96-intel -0x8p-16448L : -0x8p-16448L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p downward ldbl-96-m68k -0x8p-16448L : -0xcp-16448L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p tonearest ldbl-96-m68k -0x8p-16448L : -0x8p-16448L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p towardzero ldbl-96-m68k -0x8p-16448L : -0x8p-16448L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p upward ldbl-96-m68k -0x8p-16448L : -0x8p-16448L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p downward ldbl-128 -0x8p-16448L : -0x8.000000000004p-16448L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p tonearest ldbl-128 -0x8p-16448L : -0x8p-16448L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p towardzero ldbl-128 -0x8p-16448L : -0x8p-16448L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p upward ldbl-128 -0x8p-16448L : -0x8p-16448L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p downward ldbl-96-m68k -0x4p-16448L : -0x8p-16448L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p tonearest ldbl-96-m68k -0x4p-16448L : -0x4p-16448L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p towardzero ldbl-96-m68k -0x4p-16448L : -0x4p-16448L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p upward ldbl-96-m68k -0x4p-16448L : -0x4p-16448L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p downward ldbl-128 -0x4p-16448L : -0x4.000000000004p-16448L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p tonearest ldbl-128 -0x4p-16448L : -0x4p-16448L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p towardzero ldbl-128 -0x4p-16448L : -0x4p-16448L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p upward ldbl-128 -0x4p-16448L : -0x4p-16448L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p downward ldbl-128 -0x4p-16496L : -0x8p-16496L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p tonearest ldbl-128 -0x4p-16496L : -0x4p-16496L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p towardzero ldbl-128 -0x4p-16496L : -0x4p-16496L : inexact-ok underflow underflow-ok errno-erange-ok
-= log1p upward ldbl-128 -0x4p-16496L : -0x4p-16496L : inexact-ok underflow underflow-ok errno-erange-ok
+= log1p downward ldbl-128ibm -0x4p-1076L : -0x8p-1076L : inexact-ok underflow errno-erange-ok
+= log1p tonearest ldbl-128ibm -0x4p-1076L : -0x4p-1076L : inexact-ok underflow errno-erange-ok
+= log1p towardzero ldbl-128ibm -0x4p-1076L : -0x4p-1076L : inexact-ok underflow errno-erange-ok
+= log1p upward ldbl-128ibm -0x4p-1076L : -0x4p-1076L : inexact-ok underflow errno-erange-ok
+= log1p downward ldbl-96-intel -0x8p-16448L : -0x1p-16444L : inexact-ok underflow errno-erange-ok
+= log1p tonearest ldbl-96-intel -0x8p-16448L : -0x8p-16448L : inexact-ok underflow errno-erange-ok
+= log1p towardzero ldbl-96-intel -0x8p-16448L : -0x8p-16448L : inexact-ok underflow errno-erange-ok
+= log1p upward ldbl-96-intel -0x8p-16448L : -0x8p-16448L : inexact-ok underflow errno-erange-ok
+= log1p downward ldbl-96-m68k -0x8p-16448L : -0xcp-16448L : inexact-ok underflow errno-erange-ok
+= log1p tonearest ldbl-96-m68k -0x8p-16448L : -0x8p-16448L : inexact-ok underflow errno-erange-ok
+= log1p towardzero ldbl-96-m68k -0x8p-16448L : -0x8p-16448L : inexact-ok underflow errno-erange-ok
+= log1p upward ldbl-96-m68k -0x8p-16448L : -0x8p-16448L : inexact-ok underflow errno-erange-ok
+= log1p downward ldbl-128 -0x8p-16448L : -0x8.000000000004p-16448L : inexact-ok underflow errno-erange-ok
+= log1p tonearest ldbl-128 -0x8p-16448L : -0x8p-16448L : inexact-ok underflow errno-erange-ok
+= log1p towardzero ldbl-128 -0x8p-16448L : -0x8p-16448L : inexact-ok underflow errno-erange-ok
+= log1p upward ldbl-128 -0x8p-16448L : -0x8p-16448L : inexact-ok underflow errno-erange-ok
+= log1p downward ldbl-96-m68k -0x4p-16448L : -0x8p-16448L : inexact-ok underflow errno-erange-ok
+= log1p tonearest ldbl-96-m68k -0x4p-16448L : -0x4p-16448L : inexact-ok underflow errno-erange-ok
+= log1p towardzero ldbl-96-m68k -0x4p-16448L : -0x4p-16448L : inexact-ok underflow errno-erange-ok
+= log1p upward ldbl-96-m68k -0x4p-16448L : -0x4p-16448L : inexact-ok underflow errno-erange-ok
+= log1p downward ldbl-128 -0x4p-16448L : -0x4.000000000004p-16448L : inexact-ok underflow errno-erange-ok
+= log1p tonearest ldbl-128 -0x4p-16448L : -0x4p-16448L : inexact-ok underflow errno-erange-ok
+= log1p towardzero ldbl-128 -0x4p-16448L : -0x4p-16448L : inexact-ok underflow errno-erange-ok
+= log1p upward ldbl-128 -0x4p-16448L : -0x4p-16448L : inexact-ok underflow errno-erange-ok
+= log1p downward ldbl-128 -0x4p-16496L : -0x8p-16496L : inexact-ok underflow errno-erange-ok
+= log1p tonearest ldbl-128 -0x4p-16496L : -0x4p-16496L : inexact-ok underflow errno-erange-ok
+= log1p towardzero ldbl-128 -0x4p-16496L : -0x4p-16496L : inexact-ok underflow errno-erange-ok
+= log1p upward ldbl-128 -0x4p-16496L : -0x4p-16496L : inexact-ok underflow errno-erange-ok
 log1p 0x1p10
 = log1p downward flt-32 0x4p+8f : 0x6.eeb4ep+0f : inexact-ok
 = log1p tonearest flt-32 0x4p+8f : 0x6.eeb4e8p+0f : inexact-ok
diff --git a/sysdeps/i386/fpu/s_log1p.S b/sysdeps/i386/fpu/s_log1p.S
index 8624249dba3..c2559a3f189 100644
--- a/sysdeps/i386/fpu/s_log1p.S
+++ b/sysdeps/i386/fpu/s_log1p.S
@@ -17,6 +17,13 @@ RCSID("$NetBSD: s_log1p.S,v 1.7 1995/05/09 00:10:58 jtc Exp $")
 limit:	.double 0.29
 one:	.double 1.0
 
+	.section .rodata.cst8,"aM",@progbits,8
+
+	.p2align 3
+	.type dbl_min,@object
+dbl_min:	.byte 0, 0, 0, 0, 0, 0, 0x10, 0
+	ASM_SIZE_DIRECTIVE(dbl_min)
+
 /*
  * Use the fyl2xp1 function when the argument is in the range -0.29 to 0.29,
  * otherwise fyl2x with the needed extra computation.
@@ -55,7 +62,25 @@ ENTRY(__log1p)
 	ret
 
 2:	fyl2xp1
-	ret
+#ifdef PIC
+	fldl	dbl_min@GOTOFF(%edx)
+#else
+	fldl	dbl_min
+#endif
+	fld	%st(1)
+	fabs
+	fucompp
+	fnstsw
+	sahf
+	jnc	1f
+	subl	$8, %esp
+	cfi_adjust_cfa_offset (8)
+	fld	%st(0)
+	fmul	%st(0)
+	fstpl	(%esp)
+	addl	$8, %esp
+	cfi_adjust_cfa_offset (-8)
+1:	ret
 
 3:	jp	4b		// in case x is ±Inf
 	fstp	%st(1)
diff --git a/sysdeps/i386/fpu/s_log1pf.S b/sysdeps/i386/fpu/s_log1pf.S
index b071e7372d1..8fca22e4ff9 100644
--- a/sysdeps/i386/fpu/s_log1pf.S
+++ b/sysdeps/i386/fpu/s_log1pf.S
@@ -17,6 +17,13 @@ RCSID("$NetBSD: s_log1pf.S,v 1.4 1995/05/09 00:13:05 jtc Exp $")
 limit:	.float 0.29
 one:	.float 1.0
 
+	.section .rodata.cst4,"aM",@progbits,4
+
+	.p2align 2
+	.type flt_min,@object
+flt_min:	.byte 0, 0, 0x80, 0
+	ASM_SIZE_DIRECTIVE(flt_min)
+
 /*
  * Use the fyl2xp1 function when the argument is in the range -0.29 to 0.29,
  * otherwise fyl2x with the needed extra computation.
@@ -55,7 +62,25 @@ ENTRY(__log1pf)
 	ret
 
 2:	fyl2xp1
-	ret
+#ifdef PIC
+	flds	flt_min@GOTOFF(%edx)
+#else
+	flds	flt_min
+#endif
+	fld	%st(1)
+	fabs
+	fucompp
+	fnstsw
+	sahf
+	jnc	1f
+	subl	$4, %esp
+	cfi_adjust_cfa_offset (4)
+	fld	%st(0)
+	fmul	%st(0)
+	fstps	(%esp)
+	addl	$4, %esp
+	cfi_adjust_cfa_offset (-4)
+1:	ret
 
 3:	jp	4b		// in case x is ±Inf
 	fstp	%st(1)
diff --git a/sysdeps/ieee754/dbl-64/s_log1p.c b/sysdeps/ieee754/dbl-64/s_log1p.c
index 86bbfbacaf1..cff555b0aac 100644
--- a/sysdeps/ieee754/dbl-64/s_log1p.c
+++ b/sysdeps/ieee754/dbl-64/s_log1p.c
@@ -78,6 +78,7 @@
  *	 See HP-15C Advanced Functions Handbook, p.193.
  */
 
+#include <float.h>
 #include <math.h>
 #include <math_private.h>
 
@@ -118,7 +119,14 @@ __log1p (double x)
 	{
 	  math_force_eval (two54 + x);          /* raise inexact */
 	  if (ax < 0x3c900000)                  /* |x| < 2**-54 */
-	    return x;
+	    {
+	      if (fabs (x) < DBL_MIN)
+		{
+		  double force_underflow = x * x;
+		  math_force_eval (force_underflow);
+		}
+	      return x;
+	    }
 	  else
 	    return x - x * x * 0.5;
 	}
diff --git a/sysdeps/ieee754/flt-32/s_log1pf.c b/sysdeps/ieee754/flt-32/s_log1pf.c
index 94c33fca16d..83a09f14142 100644
--- a/sysdeps/ieee754/flt-32/s_log1pf.c
+++ b/sysdeps/ieee754/flt-32/s_log1pf.c
@@ -13,6 +13,7 @@
  * ====================================================
  */
 
+#include <float.h>
 #include <math.h>
 #include <math_private.h>
 
@@ -48,7 +49,14 @@ __log1pf(float x)
 	    if(ax<0x31000000) {			/* |x| < 2**-29 */
 		math_force_eval(two25+x);	/* raise inexact */
 		if (ax<0x24800000)		/* |x| < 2**-54 */
+		  {
+		    if (fabsf (x) < FLT_MIN)
+		      {
+			float force_underflow = x * x;
+			math_force_eval (force_underflow);
+		      }
 		    return x;
+		  }
 		else
 		    return x - x*x*(float)0.5;
 	    }
diff --git a/sysdeps/ieee754/ldbl-128/s_log1pl.c b/sysdeps/ieee754/ldbl-128/s_log1pl.c
index b70a55b758a..ff759bc000f 100644
--- a/sysdeps/ieee754/ldbl-128/s_log1pl.c
+++ b/sysdeps/ieee754/ldbl-128/s_log1pl.c
@@ -53,6 +53,7 @@
     <http://www.gnu.org/licenses/>.  */
 
 
+#include <float.h>
 #include <math.h>
 #include <math_private.h>
 
@@ -140,6 +141,11 @@ __log1pl (long double xm1)
 
   if ((hx & 0x7fffffff) < 0x3f8e0000)
     {
+      if (fabsl (xm1) < LDBL_MIN)
+	{
+	  long double force_underflow = xm1 * xm1;
+	  math_force_eval (force_underflow);
+	}
       if ((int) xm1 == 0)
 	return xm1;
     }