diff --git a/compat/win/winnt.h b/compat/win/winnt.h
index 674b70e9..6a5e0164 100644
--- a/compat/win/winnt.h
+++ b/compat/win/winnt.h
@@ -29,6 +29,28 @@ struct PROCESSOR_POWER_INFORMATION {
   ULONG CurrentIdleState;
 };
 
+// 10.0.10240.0 SDK
+
+#ifndef PROCESSOR_ARCHITECTURE_ARM64
+#define PROCESSOR_ARCHITECTURE_ARM64 12
+#endif
+
+#ifndef PF_ARM_V8_INSTRUCTIONS_AVAILABLE
+#define PF_ARM_V8_INSTRUCTIONS_AVAILABLE 29
+#endif
+
+#ifndef PF_ARM_V8_CRYPTO_INSTRUCTIONS_AVAILABLE
+#define PF_ARM_V8_CRYPTO_INSTRUCTIONS_AVAILABLE 30
+#endif
+
+#ifndef PF_ARM_V8_CRC32_INSTRUCTIONS_AVAILABLE
+#define PF_ARM_V8_CRC32_INSTRUCTIONS_AVAILABLE 31
+#endif
+
+#ifndef PF_RDTSCP_INSTRUCTION_AVAILABLE
+#define PF_RDTSCP_INSTRUCTION_AVAILABLE 32
+#endif
+
 // 10.0.14393.0 SDK
 
 #ifndef PROCESSOR_ARCHITECTURE_ARM32_ON_WIN64