Make abs handle bignums

* src/floatfns.c (Fabs): Handle bignums.
* test/src/floatfns-tests.el (bignum-abs): New test.

1 files changed, 17 insertions, 2 deletions

diff --git a/src/floatfns.c b/src/floatfns.c
index bd3f2dec80a..6d7fc1452d3 100644
--- a/src/floatfns.c
+++ b/src/floatfns.c
@@ -275,9 +275,24 @@ DEFUN ("abs", Fabs, Sabs, 1, 1, 0,
        doc: /* Return the absolute value of ARG.  */)
   (register Lisp_Object arg)
 {
-  CHECK_FIXNUM_OR_FLOAT (arg);
+  CHECK_NUMBER (arg);
 
-  if (FLOATP (arg))
+  if (BIGNUMP (arg))
+    {
+      mpz_t val;
+      mpz_init (val);
+      mpz_abs (val, XBIGNUM (arg)->value);
+      arg = make_number (val);
+      mpz_clear (val);
+    }
+  else if (FIXNUMP (arg) && XINT (arg) == MOST_NEGATIVE_FIXNUM)
+    {
+      mpz_t val;
+      mpz_init_set_si (val, - MOST_NEGATIVE_FIXNUM);
+      arg = make_number (val);
+      mpz_clear (val);
+    }
+  else if (FLOATP (arg))
     arg = make_float (fabs (XFLOAT_DATA (arg)));
   else if (XINT (arg) < 0)
     XSETINT (arg, - XINT (arg));