[vm] Fix kernel_isolate use_field_guard flag for kbc

Change-Id: Iaebc204c57cff9d01e1be3db9b2c16ca3a839c38
Reviewed-on: https://dart-review.googlesource.com/69006
Reviewed-by: Ryan Macnak <[email protected]>
Reviewed-by: Régis Crelier <[email protected]>
Commit-Queue: Zach Anderson <[email protected]>

Author: zanderso

runtime/vm/clustered_snapshot.cc

@@ -5357,7 +5357,7 @@ RawApiError* Deserializer::VerifyVersionAndFeatures(Isolate* isolate) {
     const intptr_t kMessageBufferSize = 1024;
     char message_buffer[kMessageBufferSize];
     char* actual_features =
-        Utils::StrNDup(features, buffer_len < 128 ? buffer_len : 128);
+        Utils::StrNDup(features, buffer_len < 1024 ? buffer_len : 1024);
     Utils::SNPrint(message_buffer, kMessageBufferSize,
                    "Snapshot not compatible with the current VM configuration: "
                    "the snapshot requires '%s' but the VM has '%s'",

runtime/vm/dart.cc

@@ -719,6 +719,11 @@ const char* Dart::FeaturesString(Isolate* isolate,
 #else
     buffer.AddString(" x64-sysv");
 #endif
+
+#if defined(DART_USE_INTERPRETER)
+    buffer.AddString(" kbc");
+#endif
+
 #elif defined(TARGET_ARCH_DBC)
 #if defined(ARCH_IS_32_BIT)
     buffer.AddString(" dbc32");

runtime/vm/kernel_isolate.cc

@@ -95,7 +95,8 @@ class RunKernelTask : public ThreadPool::Task {
     api_flags.reify_generic_functions = false;
     api_flags.strong = false;
     api_flags.sync_async = false;
-#if !defined(DART_PRECOMPILER) && !defined(TARGET_ARCH_DBC)
+#if !defined(DART_PRECOMPILER) && !defined(TARGET_ARCH_DBC) &&                 \
+    !defined(DART_USE_INTERPRETER)
     api_flags.use_field_guards = true;
 #endif
 #if !defined(DART_PRECOMPILER)