From ef9ccf4b9a1689e7c6b1d465b6b6cf6964fe1d41 Mon Sep 17 00:00:00 2001
From: Taylor R Campbell <campbell@mumble.net>
Date: Tue, 4 Jun 2013 17:18:36 +0000
Subject: [PATCH] Make NUMBER->STRING give negative flonum zero a minus sign.

---
 src/runtime/dragon4.scm | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/runtime/dragon4.scm b/src/runtime/dragon4.scm
index 313bd887c..98c04ffcd 100644
--- a/src/runtime/dragon4.scm
+++ b/src/runtime/dragon4.scm
@@ -79,7 +79,8 @@ not much different to numbers within a few orders of magnitude of 1.
 		     (string-copy "#[-inf]")
 		     (string-append "-" (x>0 x)))))
 	      ((flo:zero? x)
-	       (string-copy "0."))
+	       ;; XXX Kludgey test for zero sign.
+	       (string-copy (if (flo:negative? (flo:atan2 x -1.)) "-0." "0.")))
 	      (else
 	       (string-copy "#[NaN]"))))))
 
-- 
2.25.1