From: Taylor R Campbell <campbell@mumble.net>
Date: Sun, 25 Aug 2019 18:32:03 +0000 (+0000)
Subject: Simplify flo:-inf.0 and flo:+inf.0.
X-Git-Tag: mit-scheme-pucked-10.1.20~11^2~67
X-Git-Url: https://birchwood-abbey.net/git?a=commitdiff_plain;h=e0dc8ee501afa84dd36dd85d8edbcc1db7a88ad6;p=mit-scheme.git

Simplify flo:-inf.0 and flo:+inf.0.

We have put out a release now whose reader understands +inf.0/-inf.0,
so we should be able to use the notation.

Fixes bugs with incorrectly raising the divide-by-zero exception flag
(even if no trap), e.g.:

;|log1mexp-invalid/(4.9406564584124654e-324)| failed 1 sub-tests out of 1 in 0. seconds:
     assertion 3: value was 3 but expected an object eqv? to 1

Here 3 = (invalid-operation divide-by-zero), 1 = (invalid-operation)
[aarch64].
---

diff --git a/src/runtime/floenv.scm b/src/runtime/floenv.scm
index db188d25f..fc6254859 100644
--- a/src/runtime/floenv.scm
+++ b/src/runtime/floenv.scm
@@ -156,7 +156,6 @@ USA.
 	   ((ucode-primitive set-trapped-float-exceptions 1)
 	    (flo:default-trapped-exceptions))
 	   ((ucode-primitive float-environment 0)))))
-  (initialize-flonum-infinities!)
   unspecific)
 
 (define (initialize-package!)
@@ -355,24 +354,5 @@ USA.
 (define (flo:nan.0)
   (flo:make-nan #f #t 0))
 
-(define flo:+inf.0)
-(define flo:-inf.0)
-(define (initialize-flonum-infinities!)
-  (if (flo:have-trap-enable/disable?)
-      (begin
-	(set! flo:+inf.0
-	      (named-lambda (flo:+inf.0)
-		(flo:with-exceptions-untrapped (flo:exception:divide-by-zero)
-					       (lambda ()
-						 (flo:/ +1. 0.)))))
-	(set! flo:-inf.0
-	      (named-lambda (flo:-inf.0)
-		(flo:with-exceptions-untrapped (flo:exception:divide-by-zero)
-					       (lambda ()
-						 (flo:/ -1. 0.)))))
-	unspecific)
-      ;; This works on macOS.  YMMV.
-      (begin
-	(set! flo:+inf.0 (named-lambda (flo:+inf.0) (flo:/ +1. 0.)))
-	(set! flo:-inf.0 (named-lambda (flo:-inf.0) (flo:/ -1. 0.)))
-	unspecific)))
\ No newline at end of file
+(define (flo:+inf.0) +inf.0)
+(define (flo:-inf.0) -inf.0)
\ No newline at end of file