mirrors/emacs
1
Fork 0
mirror of git://git.sv.gnu.org/emacs.git synced 2025-12-15 10:30:25 -08:00
Code Issues Projects Releases Wiki Activity

Fix byte-compilation of (+ -0.0) (bug#42597)

Browse source 
* lisp/emacs-lisp/bytecomp.el (byte-compile-associative):
Translate numerical identity expressions, such as (+ x) and (* x),
into (* x 1) since the previous translation (+ x 0) gets it wrong
for x = -0.0.
* test/lisp/emacs-lisp/bytecomp-tests.el
(byte-opt-testsuite-arith-data): Add test cases.
This commit is contained in:
Mattias Engdegård 2020-08-03 15:29:41 +02:00
parent b83f274869
commit 204273c3b9
2 changed files with 8 additions and 3 deletions
Download patch file Download diff file Expand all files Collapse all files

6
lisp/emacs-lisp/bytecomp.el
View file

@ -3733,7 +3733,7 @@ discarding."
;; Compile a function that accepts one or more args and is right-associative.
;; We do it by left-associativity so that the operations
;; are done in the same order as in interpreted code.
;; We treat the one-arg case, as in (+ x), like (+ x 0).
;; We treat the one-arg case, as in (+ x), like (* x 1).
;; in order to convert markers to numbers, and trigger expected errors.
(defun byte-compile-associative (form)
(if (cdr form)
@ -3748,8 +3748,8 @@ discarding."
(setq args (copy-sequence (cdr form)))
(byte-compile-form (car args))
(setq args (cdr args))
(or args (setq args '(0)
opcode (get '+ 'byte-opcode)))
(or args (setq args '(1)
opcode (get '* 'byte-opcode)))
(dolist (arg args)
(byte-compile-form arg)
(byte-compile-out opcode 0))))