diff --git a/dep/vixl/include/vixl/aarch64/assembler-aarch64.h b/dep/vixl/include/vixl/aarch64/assembler-aarch64.h
index 7d9546657..b806cbfc2 100644
--- a/dep/vixl/include/vixl/aarch64/assembler-aarch64.h
+++ b/dep/vixl/include/vixl/aarch64/assembler-aarch64.h
@@ -35,6 +35,11 @@
 #include "../utils-vixl.h"
 #include "operands-aarch64.h"
 
+#ifdef _MSC_VER
+// This is defined in arm_neon.h on MSVC.
+#undef mvn
+#endif
+
 namespace vixl {
 namespace aarch64 {