From e2fe959fe2a450f74271d4d3c4b0d9456f889125 Mon Sep 17 00:00:00 2001
From: Szabolcs Nagy <nsz@port70.net>
Date: Tue, 13 Nov 2012 00:49:55 +0100
Subject: [PATCH] math: raise flags in logl.c on <= 0 arguments

---
 src/math/log2l.c | 3 +--
 src/math/logl.c  | 9 ++-------
 2 files changed, 3 insertions(+), 9 deletions(-)

diff --git a/src/math/log2l.c b/src/math/log2l.c
index 76a7aacd..345b395d 100644
--- a/src/math/log2l.c
+++ b/src/math/log2l.c
@@ -108,8 +108,7 @@ static const long double S[4] = {
 
 long double log2l(long double x)
 {
-	long double z;
-	long double y;
+	long double y, z;
 	int e;
 
 	if (isnan(x))
diff --git a/src/math/logl.c b/src/math/logl.c
index ffd81038..ef2b5515 100644
--- a/src/math/logl.c
+++ b/src/math/logl.c
@@ -50,11 +50,6 @@
  * In the tests over the interval exp(+-10000), the logarithms
  * of the random arguments were uniformly distributed over
  * [-10000, +10000].
- *
- * ERROR MESSAGES:
- *
- * log singularity:  x = 0; returns -INFINITY
- * log domain:       x < 0; returns NAN
  */
 
 #include "libm.h"
@@ -121,8 +116,8 @@ long double logl(long double x)
 		return x;
 	if (x <= 0.0) {
 		if (x == 0.0)
-			return -INFINITY;
-		return NAN;
+			return -1/(x+0); /* -inf with divbyzero */
+		return 0/0.0f; /* nan with invalid */
 	}
 
 	/* separate mantissa from exponent */
-- 
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