[win32] Suppress win32 swiftshader warnings (#562)

cbracken · web-flow · commit 60d942d91bf9 · 2022-04-13T16:19:46.000-07:00
Suppresses several Windows-specific warnings emitted during swiftshader builds: * On swiftshader builds against Win32 C++ headers, warnings are emitted about subclassing std::iterator, which was deprecated in C++17. This affects a header file in swiftshader's third-party directory: third_party/swiftshader/third_party/llvm-subzero/include/llvm/ADT/iterator.h * Three functions in libVulkan.cpp are re-declared with a difference in dllexport attribute only. * Silence implicit string conversion warnings in two places in swiftshader where asserts of the form assert(!"Error msg") are used. Issue: #59199
diff --git a/build/secondary/third_party/swiftshader_flutter/BUILD.gn b/build/secondary/third_party/swiftshader_flutter/BUILD.gn
@@ -27,6 +27,22 @@ config("internal_config") {
   ]
 
   if (is_win) {
+    cflags += [
+      # Silence warnings about redeclaration of vk_icdGetInstanceProcAddr,
+      # vk_icdNegotiateLoaderICDInterfaceVersion, vkGetInstanceProcAddr in
+      # //third_party/swiftshader/src/Vulkan/libVulkan.cpp.
+      "-Wno-dll-attribute-on-redeclaration",
+      # Silence warnings about strings (ab)used in assertions in
+      # FrameBufferDD.cpp. e.g. assert(!"Failed to initialize graphics:...")
+      "-Wno-string-conversion",
+    ]
+
+    defines += [
+      # std::iterator is deprecated as a base class, but used in
+      # third_party/swiftshader/third_party/llvm-subzero/include/llvm/ADT/iterator.h
+      "_SILENCE_CXX17_ITERATOR_BASE_CLASS_DEPRECATION_WARNING",
+    ]
+
     libs = [
       "user32.lib",
       "gdi32.lib",
