From: Taylor R Campbell <campbell@mumble.net>
Date: Fri, 14 Dec 2018 15:18:04 +0000 (+0000)
Subject: Use integer bit tests in FLONUM-IS-NEGATIVE?.
X-Git-Tag: mit-scheme-pucked-10.1.9~3^2~35^2~18
X-Git-Url: https://birchwood-abbey.net/git?a=commitdiff_plain;h=65ac645cd052bd307f9e2001a5b7084cfa1a01dd;p=mit-scheme.git

Use integer bit tests in FLONUM-IS-NEGATIVE?.

Otherwise this raises an exception for sNaN on i387.
---

diff --git a/src/microcode/flonum.c b/src/microcode/flonum.c
index 14bcb943e..b79ea6349 100644
--- a/src/microcode/flonum.c
+++ b/src/microcode/flonum.c
@@ -525,7 +525,9 @@ DEFINE_PRIMITIVE ("FLONUM-IS-NORMAL?", Prim_flonum_is_normal_p, 1, 1, 0)
 DEFINE_PRIMITIVE ("FLONUM-IS-NEGATIVE?", Prim_flonum_is_negative_p, 1, 1, 0)
 {
   PRIMITIVE_HEADER (1);
-  PRIMITIVE_RETURN (BOOLEAN_TO_OBJECT (signbit (arg_flonum (1))));
+  PRIMITIVE_RETURN
+    (BOOLEAN_TO_OBJECT
+     ((UINT64_C (0x8000000000000000)) & (arg_flonum_binary64 (1))));
 }
 
 DEFINE_PRIMITIVE ("FLONUM-IS-GREATER?", Prim_flonum_is_greater_p, 2, 2, 0)