Fix and improve test for enum repr sizes

src/test/run-pass/multiple-reprs.rs

@@ -9,7 +9,8 @@
 // except according to those terms.
 
 
-use std::mem::size_of;
+use std::mem::{size_of, align_of};
+use std::os::raw::c_int;
 
 // The two enums that follow are designed so that bugs trigger layout optimization.
 // Specifically, if either of the following reprs used here is not detected by the compiler,
@@ -27,6 +28,38 @@ enum E2 {
     B(u8, u16, u8)
 }
 
+// Check that repr(int) and repr(C) are in fact different from the above
+
+#[repr(u8)]
+enum E3 {
+    A(u8, u16, u8),
+    B(u8, u16, u8)
+}
+
+#[repr(u16)]
+enum E4 {
+    A(u8, u16, u8),
+    B(u8, u16, u8)
+}
+
+#[repr(u32)]
+enum E5 {
+    A(u8, u16, u8),
+    B(u8, u16, u8)
+}
+
+#[repr(u64)]
+enum E6 {
+    A(u8, u16, u8),
+    B(u8, u16, u8)
+}
+
+#[repr(C)]
+enum E7 {
+    A(u8, u16, u8),
+    B(u8, u16, u8)
+}
+
 // From pr 37429
 
 #[repr(C,packed)]
@@ -37,7 +70,20 @@ pub struct p0f_api_query {
 }
 
 pub fn main() {
-    assert_eq!(size_of::<E1>(), 6);
-    assert_eq!(size_of::<E2>(), 6);
+    assert_eq!(size_of::<E1>(), 8);
+    assert_eq!(size_of::<E2>(), 8);
+    assert_eq!(size_of::<E3>(), 6);
+    assert_eq!(size_of::<E4>(), 8);
+    assert_eq!(size_of::<E5>(), align_size(10, align_of::<u32>()));
+    assert_eq!(size_of::<E6>(), align_size(14, align_of::<u64>()));
+    assert_eq!(size_of::<E7>(), align_size(6 + size_of::<c_int>(), align_of::<c_int>()));
     assert_eq!(size_of::<p0f_api_query>(), 21);
 }
+
+fn align_size(size: usize, align: usize) -> usize {
+    if size % align != 0 {
+        size + (align - (size % align))
+    } else {
+        size
+    }
+}