Add test for repr(align=x)

src/test/ui/repr-align-assign.rs

@@ -0,0 +1,17 @@
+// Copyright 2018 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.
+
+#[repr(align=8)] //~ ERROR incorrect `repr(align)` attribute format
+struct A(u64);
+
+#[repr(align="8")] //~ ERROR incorrect `repr(align)` attribute format
+struct B(u64);
+
+fn main() {}

src/test/ui/repr-align-assign.stderr

@@ -0,0 +1,15 @@
+error[E0693]: incorrect `repr(align)` attribute format
+  --> $DIR/repr-align-assign.rs:11:8
+   |
+LL | #[repr(align=8)] //~ ERROR incorrect `repr(align)` attribute format
+   |        ^^^^^^^ help: use parentheses instead: `align(8)`
+
+error[E0693]: incorrect `repr(align)` attribute format
+  --> $DIR/repr-align-assign.rs:14:8
+   |
+LL | #[repr(align="8")] //~ ERROR incorrect `repr(align)` attribute format
+   |        ^^^^^^^^^ help: use parentheses instead: `align(8)`
+
+error: aborting due to 2 previous errors
+
+For more information about this error, try `rustc --explain E0693`.