add an align parameter to exchange_malloc

Closes #13094

1 files changed, 44 insertions, 1 deletions

diff --git a/src/libstd/rt/global_heap.rs b/src/libstd/rt/global_heap.rs
index 7d54c3faf42..c8808b6e821 100644
--- a/src/libstd/rt/global_heap.rs
+++ b/src/libstd/rt/global_heap.rs
@@ -68,7 +68,7 @@ pub unsafe fn realloc_raw(ptr: *mut u8, size: uint) -> *mut u8 {
 }
 
 /// The allocator for unique pointers without contained managed pointers.
-#[cfg(not(test))]
+#[cfg(not(test), stage0)]
 #[lang="exchange_malloc"]
 #[inline]
 pub unsafe fn exchange_malloc(size: uint) -> *mut u8 {
@@ -85,6 +85,23 @@ pub unsafe fn exchange_malloc(size: uint) -> *mut u8 {
     }
 }
 
+/// The allocator for unique pointers without contained managed pointers.
+#[cfg(not(test), not(stage0))]
+#[lang="exchange_malloc"]
+#[inline]
+pub unsafe fn exchange_malloc(size: uint, _align: uint) -> *mut u8 {
+    // The compiler never calls `exchange_free` on ~ZeroSizeType, so zero-size
+    // allocations can point to this `static`. It would be incorrect to use a null
+    // pointer, due to enums assuming types like unique pointers are never null.
+    static EMPTY: () = ();
+
+    if size == 0 {
+        &EMPTY as *() as *mut u8
+    } else {
+        malloc_raw(size)
+    }
+}
+
 // FIXME: #7496
 #[cfg(not(test))]
 #[lang="closure_exchange_malloc"]
@@ -118,6 +135,32 @@ pub unsafe fn exchange_free(ptr: *u8) {
     free(ptr as *mut c_void);
 }
 
+// hack for libcore
+#[no_mangle]
+#[doc(hidden)]
+#[deprecated]
+#[cfg(stage0)]
+pub extern "C" fn rust_malloc(size: uint) -> *mut u8 {
+    unsafe { exchange_malloc(size) }
+}
+
+// hack for libcore
+#[no_mangle]
+#[doc(hidden)]
+#[deprecated]
+#[cfg(not(stage0))]
+pub extern "C" fn rust_malloc(size: uint, align: uint) -> *mut u8 {
+    unsafe { exchange_malloc(size, align) }
+}
+
+// hack for libcore
+#[no_mangle]
+#[doc(hidden)]
+#[deprecated]
+pub extern "C" fn rust_free(ptr: *u8) {
+    unsafe { exchange_free(ptr) }
+}
+
 #[cfg(test)]
 mod bench {
     extern crate test;