Add tracking of packed repr, use it to highlight unsafe refs

Taking a reference to a misaligned field on a packed struct is an
unsafe operation. Highlight that behavior. Currently, the misaligned
part isn't tracked, so this highlight is a bit too aggressive.

1 files changed, 11 insertions, 0 deletions

diff --git a/crates/ra_ide/src/syntax_highlighting/tests.rs b/crates/ra_ide/src/syntax_highlighting/tests.rs
index 09062c38e..f2c078d34 100644
--- a/crates/ra_ide/src/syntax_highlighting/tests.rs
+++ b/crates/ra_ide/src/syntax_highlighting/tests.rs
@@ -292,6 +292,13 @@ struct TypeForStaticMut {
 
 static mut global_mut: TypeForStaticMut = TypeForStaticMut { a: 0 };
 
+#[repr(packed)]
+struct Packed {
+    a: u16,
+    b: u8,
+    c: u32,
+}
+
 fn main() {
     let x = &5 as *const usize;
     let u = Union { b: 0 };
@@ -306,6 +313,10 @@ fn main() {
         let y = *(x);
         let z = -x;
         let a = global_mut.a;
+        let packed = Packed { a: 0, b: 0, c: 0 };
+        let a = &packed.a;
+        let b = &packed.b;
+        let c = &packed.c;
     }
 }
 "#