Exception when compare integer against big integer

[Rex Cheung]

Following code in mRuby 3.2 and master branch causes ArgumentError exception. mRuby 3.1 is not affected since it does not have built-in bigint.

a=64
b=2**64
puts "a=#{a.class}"
puts "b=#{b.class}"
puts "num #{a < b}"

a=Integer
b=Integer
trace (most recent call last):
	[1] ../../lgtv_2024_mruby32/test.rb:5
../../lgtv_2024_mruby32/test.rb:5:in <: comparison of Integer with Integer failed (ArgumentError)

There's no problem if the statement a < b changed to b > a.
The function (cmpnum() in src/numeric.c) handles comparison handles the case the first parameter (v1) is big integer, but not the second one. A quick and dirty fix appears to solve the issue:

diff --git a/src/numeric.c b/src/numeric.c
index 4ad523f22..c32f0024d 100644
--- a/src/numeric.c
+++ b/src/numeric.c
@@ -2031,6 +2031,10 @@ cmpnum(mrb_state *mrb, mrb_value v1, mrb_value v2)
   if (mrb_bigint_p(v1)) {
     return mrb_bint_cmp(mrb, v1, v2);
   }
+  if (mrb_bigint_p(v2)) {
+    mrb_int ret = mrb_bint_cmp(mrb, v2, v1);
+    return (-2 != ret)? -ret : ret;
+  }
 #endif
 
 #ifdef MRB_NO_FLOAT