Logging of newtyped uints is broken

[nikomatsakis]

Running this program:

enum Foo = uint;

fn main() {
    let x = Foo(1);
    let y = 1;
    io::println(fmt!("%?, %?", x, y));
}

yields the output:

, 1

Not so good.

[nikomatsakis]

This is a real hindrance to debugging the type checker, so I put it as a blocker for 0.4.

[Blei]

Even more interesting:

enum Foo = uint;

fn main() {
    let x = Foo(0);
    let y = Foo(1);
    io::println(fmt!("%?, %?", x, y));
}

Produces:

Foo(8892280), 

Where the printed value changes in each invocation...

[Blei]

This issue can be fixed with

diff --git a/src/libcore/repr.rs b/src/libcore/repr.rs
index a0d6b01..610cc6f 100644
--- a/src/libcore/repr.rs
+++ b/src/libcore/repr.rs
@@ -881,13 +881,13 @@ impl ReprPrinterWrapper : TyVisitor {
             let mut enum_state = stack.last();
             match enum_state.state {
                 PreVariant => {
-                    let disr_ptr = self.printer.ptr as *int;
-                    if *disr_ptr == disr_val {
+                    //let disr_ptr = self.printer.ptr as *int;
+                    //if *disr_ptr == disr_val {
                         enum_state.state = InVariant;
                         self.printer.writer.write_str(name);
-                        self.printer.bump(sys::size_of::<int>());
+                        //self.printer.bump(sys::size_of::<int>());
                         stack.set_elt(stack.len() - 1, enum_state);
-                    }
+                    //}
                 }
                 InVariant | PostVariant => {}
             }

This is almost certainly not the correct fix, but might be a hint about where the problem is.

[nikomatsakis]

Thanks, I hadn't gotten around to opening repr.rs, but after your
comments the fix seems pretty obvious. Will push a patch soon.

[nikomatsakis]

Oh, I should rebase before I repeat @pcwalton's work :)