rustc: Warn when int or uint is used in a native type decl

Issue rust-lang#1403

Author: lht

src/comp/middle/typeck.rs

@@ -2678,6 +2678,25 @@ fn check_method(ccx: @crate_ctxt, method: @ast::method) {
     check_fn(ccx, ast::proto_bare, method.decl, method.body, method.id, none);
 }
 
+fn check_native_fn(ccx: @crate_ctxt, decl: ast::fn_decl) {
+    let tys = vec::map(decl.inputs) {|a| a.ty };
+    for ty in (tys + [decl.output]) {
+        alt ty.node {
+          ast::ty_int(ast::ty_i.) {
+            ccx.tcx.sess.span_warn(
+                ty.span, "found rust type `int` in native module, while " +
+                         "ctypes::c_int or ctypes::long should be used");
+          }
+          ast::ty_uint(ast::ty_u.) {
+            ccx.tcx.sess.span_warn(
+                ty.span, "found rust type `uint` in native module, while " +
+                         "ctypes::c_uint or ctypes::ulong should be used");
+          }
+          _ { }
+        }
+    }
+}
+
 fn check_item(ccx: @crate_ctxt, it: @ast::item) {
     alt it.node {
       ast::item_const(_, e) { check_const(ccx, it.span, e, it.id); }
@@ -2688,6 +2707,16 @@ fn check_item(ccx: @crate_ctxt, it: @ast::item) {
       ast::item_res(decl, tps, body, dtor_id, _) {
         check_fn(ccx, ast::proto_bare, decl, body, dtor_id, none);
       }
+      ast::item_native_mod(nmod) {
+        for ni in nmod.items {
+            alt ni.node {
+              ast::native_item_fn(decl, tps) {
+                check_native_fn(ccx, decl);
+              }
+              _ { }
+            }
+        }
+      }
       ast::item_impl(tps, _, ty, ms) {
         ccx.self_infos += [self_impl(ast_ty_to_ty(ccx.tcx, m_check, ty))];
         for m in ms { check_method(ccx, m); }

src/test/compile-fail/warn-native-int-types.rs

@@ -0,0 +1,9 @@
+//error-pattern:ctypes::c_int or ctypes::long should be used
+native mod xx {
+  fn strlen(str: *u8) -> uint;
+  fn foo(x: int, y: uint);
+}
+
+fn main() {
+  "let compile fail to verify warning message" = 999;
+}