Add test for issue 2214

Author: catamorphism

src/test/run-pass/issue-2214.rs

@@ -0,0 +1,18 @@
+import libc::{c_double, c_int};
+
+fn lgamma(n: c_double, value: &mut int) -> c_double {
+  ret m::lgamma(n, value as &mut c_int);
+}
+
+#[link_name = "m"]
+#[abi = "cdecl"]
+native mod m {
+    #[link_name="lgamma_r"] fn lgamma(n: c_double, sign: &mut c_int)
+      -> c_double;
+}
+
+fn main() {
+  let mut y: int = 5;
+  let x: &mut int = &mut y;
+  assert (lgamma(1.0 as c_double, x) == 42.0 as c_double);
+}