Fix write barrier parameter type (mmtk#273)

Upstream PR: mmtk/mmtk-core#1130

---------

Co-authored-by: mmtkgc-bot <[email protected]>

Author: wks

mmtk/Cargo.lock

@@ -32,7 +32,7 @@ memoffset = "0.9.0"
 # - change branch
 # - change repo name
 # But other changes including adding/removing whitespaces in commented lines may break the CI.
-mmtk = { git = "https://github.com/mmtk/mmtk-core.git", rev = "a02803b4104519ff2289234101a2dd8ceedd1bc7" }
+mmtk = { git = "https://github.com/mmtk/mmtk-core.git", rev = "fea59e4f5cc6176093da1d8efa7d7b3b4b8d0fa7" }
 # Uncomment the following to build locally
 # mmtk = { path = "../repos/mmtk-core" }
 

mmtk/Cargo.toml

@@ -401,12 +401,12 @@ pub extern "C" fn mmtk_object_reference_write_pre(
     mutator: *mut libc::c_void,
     src: ObjectReference,
     slot: Address,
-    target: ObjectReference,
+    target: NullableObjectReference,
 ) {
     with_mutator!(|mutator| {
         mutator
             .barrier()
-            .object_reference_write_pre(src, slot.into(), target);
+            .object_reference_write_pre(src, slot.into(), target.into());
     })
 }
 
@@ -416,12 +416,12 @@ pub extern "C" fn mmtk_object_reference_write_post(
     mutator: *mut libc::c_void,
     src: ObjectReference,
     slot: Address,
-    target: ObjectReference,
+    target: NullableObjectReference,
 ) {
     with_mutator!(|mutator| {
         mutator
             .barrier()
-            .object_reference_write_post(src, slot.into(), target);
+            .object_reference_write_post(src, slot.into(), target.into());
     })
 }
 
@@ -431,12 +431,12 @@ pub extern "C" fn mmtk_object_reference_write_slow(
     mutator: *mut libc::c_void,
     src: ObjectReference,
     slot: Address,
-    target: ObjectReference,
+    target: NullableObjectReference,
 ) {
     with_mutator!(|mutator| {
         mutator
             .barrier()
-            .object_reference_write_slow(src, slot.into(), target);
+            .object_reference_write_slow(src, slot.into(), target.into());
     })
 }