diff --git a/runtime/vm/compiler/assembler/assembler_arm64.cc b/runtime/vm/compiler/assembler/assembler_arm64.cc
index 7ca178c..4fb6ef4 100644
--- a/runtime/vm/compiler/assembler/assembler_arm64.cc
+++ b/runtime/vm/compiler/assembler/assembler_arm64.cc
@@ -1206,7 +1206,7 @@
 #if defined(TARGET_OS_FUCHSIA)
   // Make any future signal handlers fail fast. Verifies our assumption in
   // EnterFrame.
-  LoadImmediate(CSP, 0);
+  orri(CSP, ZR, Immediate(16));
 #endif
 }
 
diff --git a/runtime/vm/dart_api_impl.cc b/runtime/vm/dart_api_impl.cc
index 1c828d1..7d9b8f5 100644
--- a/runtime/vm/dart_api_impl.cc
+++ b/runtime/vm/dart_api_impl.cc
@@ -2342,7 +2342,7 @@
 
 DART_EXPORT Dart_Handle Dart_StringLength(Dart_Handle str, intptr_t* len) {
   Thread* thread = Thread::Current();
-  CHECK_ISOLATE(thread->isolate());
+  DARTSCOPE(thread);
   ReusableObjectHandleScope reused_obj_handle(thread);
   const String& str_obj = Api::UnwrapStringHandle(reused_obj_handle, str);
   if (str_obj.IsNull()) {
diff --git a/runtime/vm/flag_list.h b/runtime/vm/flag_list.h
index 1228d17..d11e203 100644
--- a/runtime/vm/flag_list.h
+++ b/runtime/vm/flag_list.h
@@ -188,7 +188,7 @@
   D(trace_zones, bool, false, "Traces allocation sizes in the zone.")          \
   P(truncating_left_shift, bool, true,                                         \
     "Optimize left shift to truncate if possible")                             \
-  C(use_bytecode_compiler, false, false, bool, false, "Compile from bytecode") \
+  P(use_bytecode_compiler, bool, false, "Compile from bytecode")               \
   P(use_compactor, bool, false, "Compact the heap during old-space GC.")       \
   P(use_cha_deopt, bool, true,                                                 \
     "Use class hierarchy analysis even if it can cause deoptimization.")       \
diff --git a/runtime/vm/object_id_ring_test.cc b/runtime/vm/object_id_ring_test.cc
index 92d3400..23593a7 100644
--- a/runtime/vm/object_id_ring_test.cc
+++ b/runtime/vm/object_id_ring_test.cc
@@ -201,18 +201,12 @@
   intptr_t raw_obj_id1 = -1;
   intptr_t raw_obj_id2 = -1;
   {
-    Api::Scope api_scope(thread);
-    Dart_Handle result;
-    // Create a string in the old heap.
-    result = Api::NewHandle(thread, String::New("old", Heap::kOld));
-    EXPECT_VALID(result);
-    intptr_t string_length = 0;
-    // Inspect string.
-    EXPECT(!Dart_IsNull(result));
-    EXPECT(Dart_IsString(result));
-    EXPECT_VALID(Dart_StringLength(result, &string_length));
-    EXPECT_EQ(3, string_length);
-    RawObject* raw_obj = Api::UnwrapHandle(result);
+    HandleScope handle_scope(thread);
+    const String& str = String::Handle(String::New("old", Heap::kOld));
+    EXPECT(!str.IsNull());
+    EXPECT_EQ(3, str.Length());
+
+    RawObject* raw_obj = Object::RawCast(str.raw());
     // Verify that it is located in old heap.
     EXPECT(raw_obj->IsOldObject());
     EXPECT_NE(Object::null(), raw_obj);
@@ -228,7 +222,7 @@
     EXPECT_NE(Object::null(), raw_obj2);
     EXPECT_EQ(RawObject::ToAddr(raw_obj), RawObject::ToAddr(raw_obj1));
     EXPECT_EQ(RawObject::ToAddr(raw_obj), RawObject::ToAddr(raw_obj2));
-    // Exit scope. Freeing result handle.
+    // Exit scope. Freeing String handle.
   }
   // Force a GC. No reference exist to the old string anymore. It should be
   // collected and the object id ring will now return the null object for
diff --git a/sdk/lib/io/embedder_config.dart b/sdk/lib/io/embedder_config.dart
index 89265cf..cbc94f7 100644
--- a/sdk/lib/io/embedder_config.dart
+++ b/sdk/lib/io/embedder_config.dart
@@ -11,6 +11,7 @@
 /// permitted to use (e.g. exit()). By default, the whole dart:io API is
 /// enabled. When a disallowed operation is attempted, an `UnsupportedError` is
 /// thrown.
+@pragma('vm:entry-point')
 abstract class _EmbedderConfig {
   /// The Isolate may set Directory.current.
   static bool _mayChdir = true;
@@ -20,12 +21,15 @@
   static bool _mayExit = true;
 
   // The Isolate may set Stdin.echoMode.
+  @pragma('vm:entry-point')
   static bool _maySetEchoMode = true;
 
   // The Isolate may set Stdin.lineMode.
+  @pragma('vm:entry-point')
   static bool _maySetLineMode = true;
 
   /// The Isolate may call sleep().
+  @pragma('vm:entry-point')
   static bool _maySleep = true;
 
   // TODO(zra): Consider adding: