diff --git a/win32/build/confutils.js b/win32/build/confutils.js
index 4fe111a8fbb..ab97a0afff9 100644
--- a/win32/build/confutils.js
+++ b/win32/build/confutils.js
@@ -3294,6 +3294,8 @@ function toolset_setup_common_cflags()
 		if (VCVERS >= 1914) {
 			ADD_FLAG("CFLAGS", "/d2FuncCache1");
 		}
+
+		ADD_FLAG("CFLAGS", "/Zc:wchar_t");
 	} else if (CLANG_TOOLSET) {
 		if (X64) {
 			ADD_FLAG('CFLAGS', '-m64');