diff --git a/include/mbedtls/aesni.h b/include/mbedtls/aesni.h
index 6741dea..9a573c4 100644
--- a/include/mbedtls/aesni.h
+++ b/include/mbedtls/aesni.h
@@ -45,6 +45,11 @@
 #define MBEDTLS_HAVE_X86_64
 #endif
 
+#if !defined(MBEDTLS_HAVE_X86) && \
+    (defined(__i386__) || defined(_M_IX86))
+#define MBEDTLS_HAVE_X86
+#endif
+
 #if defined(MBEDTLS_AESNI_C)
 
 /* Can we do AESNI with intrinsics?