diff options
| -rw-r--r-- | src/floatfns.c | 7 | ||||
| -rw-r--r-- | test/src/floatfns-tests.el | 5 |
2 files changed, 10 insertions, 2 deletions
diff --git a/src/floatfns.c b/src/floatfns.c index 2f33b8652b2..13ab7b0359f 100644 --- a/src/floatfns.c +++ b/src/floatfns.c @@ -355,6 +355,8 @@ rounding_driver (Lisp_Object arg, Lisp_Object divisor, CHECK_NUMBER (divisor); if (!FLOATP (arg) && !FLOATP (divisor)) { + /* Divide as integers. Converting to double might lose + info, even for fixnums; also see the FIXME below. */ if (EQ (divisor, make_fixnum (0))) xsignal0 (Qarith_error); int_divide (mpz[0], @@ -363,10 +365,11 @@ rounding_driver (Lisp_Object arg, Lisp_Object divisor, return make_integer_mpz (); } - double f1 = FLOATP (arg) ? XFLOAT_DATA (arg) : XFIXNUM (arg); - double f2 = FLOATP (divisor) ? XFLOAT_DATA (divisor) : XFIXNUM (divisor); + double f1 = XFLOATINT (arg); + double f2 = XFLOATINT (divisor); if (! IEEE_FLOATING_POINT && f2 == 0) xsignal0 (Qarith_error); + /* FIXME: This division rounds, so the result is double-rounded. */ d = f1 / f2; } diff --git a/test/src/floatfns-tests.el b/test/src/floatfns-tests.el index d41b08f7965..9a382058b43 100644 --- a/test/src/floatfns-tests.el +++ b/test/src/floatfns-tests.el @@ -70,6 +70,11 @@ (should (= n (floor n))) (should (= n (round n))) (should (= n (truncate n))) + (let ((-n (- n)) + (f (float n)) + (-f (- (float n)))) + (should (= 1 (round n f) (round -n -f) (round f n) (round -f -n))) + (should (= -1 (round -n f) (round n -f) (round f -n) (round -f n)))) (dolist (d ns) (let ((q (/ n d)) (r (% n d)) |