Emit 'dllimport' attribute for dylib foreign items on Windows.

src/test/codegen/dllimports/auxiliary/dummy.rs

@@ -0,0 +1,16 @@
+// Copyright 2016 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// no-prefer-dynamic
+#![crate_type = "staticlib"]
+
+// Since codegen tests don't actually perform linking, this library doesn't need to export
+// any symbols.  It's here just to satisfy the compiler looking for a .lib file when processing
+// #[link(...)] attributes in wrapper.rs.

src/test/codegen/dllimports/auxiliary/wrapper.rs

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+// Copyright 2016 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// no-prefer-dynamic
+#![crate_type = "rlib"]
+
+#[link(name = "dummy", kind="dylib")]
+extern "C" {
+    pub fn dylib_func2(x: i32) -> i32;
+    pub static dylib_global2: i32;
+}
+
+#[link(name = "dummy", kind="static")]
+extern "C" {
+    pub fn static_func2(x: i32) -> i32;
+    pub static static_global2: i32;
+}

src/test/codegen/dllimports/main.rs

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+// Copyright 2016 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// This test is for Windows only.
+// ignore-android
+// ignore-bitrig
+// ignore-macos
+// ignore-dragonfly
+// ignore-freebsd
+// ignore-haiku
+// ignore-ios
+// ignore-linux
+// ignore-netbsd
+// ignore-openbsd
+// ignore-solaris
+// ignore-emscripten
+
+// aux-build:dummy.rs
+// aux-build:wrapper.rs
+
+extern crate wrapper;
+
+// Check that external symbols coming from foreign dylibs are adorned with 'dllimport',
+// whereas symbols coming from foreign staticlibs are not. (RFC-1717)
+
+// CHECK: @dylib_global1 = external dllimport local_unnamed_addr global i32
+// CHECK: @dylib_global2 = external dllimport local_unnamed_addr global i32
+// CHECK: @static_global1 = external local_unnamed_addr global i32
+// CHECK: @static_global2 = external local_unnamed_addr global i32
+
+// CHECK: declare dllimport i32 @dylib_func1(i32)
+// CHECK: declare dllimport i32 @dylib_func2(i32)
+// CHECK: declare i32 @static_func1(i32)
+// CHECK: declare i32 @static_func2(i32)
+
+#[link(name = "dummy", kind="dylib")]
+extern "C" {
+    pub fn dylib_func1(x: i32) -> i32;
+    pub static dylib_global1: i32;
+}
+
+#[link(name = "dummy", kind="static")]
+extern "C" {
+    pub fn static_func1(x: i32) -> i32;
+    pub static static_global1: i32;
+}
+
+fn main() {
+    unsafe {
+        dylib_func1(dylib_global1);
+        wrapper::dylib_func2(wrapper::dylib_global2);
+
+        static_func1(static_global1);
+        wrapper::static_func2(wrapper::static_global2);
+    }
+}