From: Taylor R Campbell <campbell@mumble.net>
Date: Tue, 4 Jun 2013 17:18:36 +0000 (+0000)
Subject: Make NUMBER->STRING give negative flonum zero a minus sign.
X-Git-Tag: release-9.2.0~161
X-Git-Url: https://birchwood-abbey.net/git?a=commitdiff_plain;h=ef9ccf4b9a1689e7c6b1d465b6b6cf6964fe1d41;p=mit-scheme.git

Make NUMBER->STRING give negative flonum zero a minus sign.
---

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]"))))))