diff --git a/src/dawn_native/d3d12/BufferD3D12.cpp b/src/dawn_native/d3d12/BufferD3D12.cpp
index 9cfc536a20..ff21dd047e 100644
--- a/src/dawn_native/d3d12/BufferD3D12.cpp
+++ b/src/dawn_native/d3d12/BufferD3D12.cpp
@@ -229,7 +229,7 @@ namespace dawn_native { namespace d3d12 {
     }
 
     MaybeError Buffer::MapAtCreationImpl(uint8_t** mappedPointer) {
-        mWrittenMappedRange = {0, GetSize()};
+        mWrittenMappedRange = {0, static_cast<size_t>(GetSize())};
         DAWN_TRY(CheckHRESULT(GetD3D12Resource()->Map(0, &mWrittenMappedRange,
                                                       reinterpret_cast<void**>(mappedPointer)),
                               "D3D12 map at creation"));
@@ -238,7 +238,7 @@ namespace dawn_native { namespace d3d12 {
 
     MaybeError Buffer::MapReadAsyncImpl(uint32_t serial) {
         mWrittenMappedRange = {};
-        D3D12_RANGE readRange = {0, GetSize()};
+        D3D12_RANGE readRange = {0, static_cast<size_t>(GetSize())};
         char* data = nullptr;
         DAWN_TRY(
             CheckHRESULT(GetD3D12Resource()->Map(0, &readRange, reinterpret_cast<void**>(&data)),
@@ -251,7 +251,7 @@ namespace dawn_native { namespace d3d12 {
     }
 
     MaybeError Buffer::MapWriteAsyncImpl(uint32_t serial) {
-        mWrittenMappedRange = {0, GetSize()};
+        mWrittenMappedRange = {0, static_cast<size_t>(GetSize())};
         char* data = nullptr;
         DAWN_TRY(CheckHRESULT(
             GetD3D12Resource()->Map(0, &mWrittenMappedRange, reinterpret_cast<void**>(&data)),
diff --git a/src/tests/end2end/WindowSurfaceTests.cpp b/src/tests/end2end/WindowSurfaceTests.cpp
index beb301b592..779622e98d 100644
--- a/src/tests/end2end/WindowSurfaceTests.cpp
+++ b/src/tests/end2end/WindowSurfaceTests.cpp
@@ -19,14 +19,16 @@
 #include "utils/GLFWUtils.h"
 
 #include <gtest/gtest.h>
-#include "GLFW/glfw3.h"
 
 #include <cstdlib>
 
+// Include windows.h before GLFW so GLFW's APIENTRY macro doesn't conflict with windows.h's.
 #if defined(DAWN_PLATFORM_WINDOWS)
 #    include "common/windows_with_undefs.h"
 #endif  // defined(DAWN_PLATFORM_WINDOWS)
 
+#include "GLFW/glfw3.h"
+
 #if defined(DAWN_USE_X11)
 #    include "common/xlib_with_undefs.h"
 #endif  // defined(DAWN_USE_X11)