diff --git a/library/sha256.c b/library/sha256.c
index da6ec18..ed47c7c 100644
--- a/library/sha256.c
+++ b/library/sha256.c
@@ -108,7 +108,7 @@
 #      include <signal.h>
 #    endif
 #  endif
-#elif !(defined(_M_ARM64) || defined(_M_ARM64EC))
+#elif !defined(MBEDTLS_PLATFORM_IS_WINDOWS_ON_ARM64)
 #  undef MBEDTLS_SHA256_USE_A64_CRYPTO_ONLY
 #  undef MBEDTLS_SHA256_USE_A64_CRYPTO_IF_PRESENT
 #endif
@@ -128,7 +128,7 @@
 {
     return 1;
 }
-#elif defined(_M_ARM64) || defined(_M_ARM64EC)
+#elif defined(MBEDTLS_PLATFORM_IS_WINDOWS_ON_ARM64)
 #define WIN32_LEAN_AND_MEAN
 #include <Windows.h>
 #include <processthreadsapi.h>