liballoc: Unconfigure tests during normal build

Remove additional libcore-like restrictions from liballoc, turns out the testing works ok if the tests are a part of liballoc itself.

src/liballoc/alloc.rs

@@ -10,6 +10,9 @@ use core::usize;
 #[doc(inline)]
 pub use core::alloc::*;
 
+#[cfg(test)]
+mod tests;
+
 extern "Rust" {
     // These are the magic symbols to call the global allocator.  rustc generates
     // them from the `#[global_allocator]` attribute if there is one, or uses the
@@ -244,36 +247,3 @@ pub fn handle_alloc_error(layout: Layout) -> ! {
     }
     unsafe { oom_impl(layout) }
 }
-
-#[cfg(test)]
-mod tests {
-    extern crate test;
-    use test::Bencher;
-    use crate::boxed::Box;
-    use crate::alloc::{Global, Alloc, Layout, handle_alloc_error};
-
-    #[test]
-    fn allocate_zeroed() {
-        unsafe {
-            let layout = Layout::from_size_align(1024, 1).unwrap();
-            let ptr = Global.alloc_zeroed(layout.clone())
-                .unwrap_or_else(|_| handle_alloc_error(layout));
-
-            let mut i = ptr.cast::<u8>().as_ptr();
-            let end = i.add(layout.size());
-            while i < end {
-                assert_eq!(*i, 0);
-                i = i.offset(1);
-            }
-            Global.dealloc(ptr, layout);
-        }
-    }
-
-    #[bench]
-    #[cfg(not(miri))] // Miri does not support benchmarks
-    fn alloc_owned_small(b: &mut Bencher) {
-        b.iter(|| {
-            let _: Box<_> = box 10;
-        })
-    }
-}