Suppress compiler and linker warnings in v8 test binaries

test/cctest/BUILD.gn

 # Copyright 2016 The V8 project authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 # Please keep this file in sync with cctest.gyp.
 
 import("../../gni/v8.gni")
 
 executable("cctest") {
   testonly = true
@@ skipping 298 matching lines @@
     "//build/win:default_exe_manifest",
   ]
 
   if (is_component_build) {
     # cctest can't be built against a shared library, so we
     # need to depend on the underlying static target in that case.
     deps += [ "../..:v8_maybe_snapshot" ]
   } else {
     deps += [ "../..:v8" ]
   }
+
+  if (is_win) {
+    # This warning is benignly triggered by the U16 and U32 macros in
+    # bytecode-utils.h.
+    # C4309: 'static_cast': truncation of constant value
+    cflags = [ "/wd4309" ]
+
+    # Suppress warnings about importing locally defined symbols.
+    if (is_component_build) {
+      ldflags = [ "/ignore:4049", "/ignore:4217" ]
+    }
+  }
 }
 
 action("resources") {
   visibility = [ ":*" ]  # Only targets in this file can depend on this.
 
   script = "../../tools/js2c.py"
 
   # The script depends on this other script, this rule causes a rebuild if it
   # changes.
   inputs = [
@@ skipping 16 matching lines @@
     "$target_gen_dir/resources.cc",
   ]
 
   args = [
     rebase_path("$target_gen_dir/resources.cc", root_build_dir),
     "TEST",
   ]
   args += rebase_path(sources, root_build_dir)
 }
 # TODO(machenbach): Migrate generate-bytecode-expectations.