From 04ccbdca6d88738e23e0d6a622ad33854c468646 Mon Sep 17 00:00:00 2001
From: Szabolcs Nagy <nsz@port70.net>
Date: Tue, 13 Nov 2012 00:21:09 +0100
Subject: [PATCH] math: raise exception flags in log1pl.c on <= -1 arguments

---
 src/math/log1pl.c | 9 ++-------
 1 file changed, 2 insertions(+), 7 deletions(-)

diff --git a/src/math/log1pl.c b/src/math/log1pl.c
index 1400d365..edb48df1 100644
--- a/src/math/log1pl.c
+++ b/src/math/log1pl.c
@@ -46,11 +46,6 @@
  *                      Relative error:
  * arithmetic   domain     # trials      peak         rms
  *    IEEE     -1.0, 9.0    100000      8.2e-20    2.5e-20
- *
- * ERROR MESSAGES:
- *
- * log singularity:  x-1 = 0; returns -INFINITY
- * log domain:       x-1 < 0; returns NAN
  */
 
 #include "libm.h"
@@ -123,8 +118,8 @@ long double log1pl(long double xm1)
 	/* Test for domain errors.  */
 	if (x <= 0.0) {
 		if (x == 0.0)
-			return -INFINITY;
-		return NAN;
+			return -1/x; /* -inf with divbyzero */
+		return 0/0.0f; /* nan with invalid */
 	}
 
 	/* Separate mantissa from exponent.
-- 
2.20.1