diff --git a/library/aes.c b/library/aes.c
index d232229..b61d089 100644
--- a/library/aes.c
+++ b/library/aes.c
@@ -34,23 +34,15 @@
 #include "mbedtls/platform_util.h"
 #include "mbedtls/error.h"
 
-#if defined(MBEDTLS_ARCH_IS_ARM64)
-#if !defined(MBEDTLS_AESCE_C) && defined(MBEDTLS_AES_USE_HARDWARE_ONLY)
-#error "MBEDTLS_AES_USE_HARDWARE_ONLY defined, but not all prerequisites"
-#endif
-#endif
-
-#if defined(MBEDTLS_ARCH_IS_X64)
-#if !defined(MBEDTLS_AESNI_C) && defined(MBEDTLS_AES_USE_HARDWARE_ONLY)
+#if defined(MBEDTLS_AES_USE_HARDWARE_ONLY)
+#if !((defined(MBEDTLS_ARCH_IS_ARM64) && defined(MBEDTLS_AESCE_C)) || \
+    (defined(MBEDTLS_ARCH_IS_X64)   && defined(MBEDTLS_AESNI_C)) || \
+    (defined(MBEDTLS_ARCH_IS_X86)   && defined(MBEDTLS_AESNI_C)))
 #error "MBEDTLS_AES_USE_HARDWARE_ONLY defined, but not all prerequisites"
 #endif
 #endif
 
 #if defined(MBEDTLS_ARCH_IS_X86)
-#if defined(MBEDTLS_AES_USE_HARDWARE_ONLY) && !defined(MBEDTLS_AESNI_C)
-#error "MBEDTLS_AES_USE_HARDWARE_ONLY defined, but not all prerequisites"
-#endif
-
 #if defined(MBEDTLS_PADLOCK_C)
 #if !defined(MBEDTLS_HAVE_ASM)
 #error "MBEDTLS_PADLOCK_C defined, but not all prerequisites"
@@ -339,7 +331,7 @@
 /*
  * Round constants
  */
-MBEDTLS_MAYBE_UNUSED static const uint32_t RCON[10] =
+MBEDTLS_MAYBE_UNUSED static const uint32_t round_constants[10] =
 {
     0x00000001, 0x00000002, 0x00000004, 0x00000008,
     0x00000010, 0x00000020, 0x00000040, 0x00000080,
@@ -370,7 +362,7 @@
 /*
  * Round constants
  */
-MBEDTLS_MAYBE_UNUSED static uint32_t RCON[10];
+MBEDTLS_MAYBE_UNUSED static uint32_t round_constants[10];
 
 /*
  * Tables generation code
@@ -401,7 +393,7 @@
      * calculate the round constants
      */
     for (i = 0, x = 1; i < 10; i++) {
-        RCON[i] = x;
+        round_constants[i] = x;
         x = XTIME(x);
     }
 
@@ -625,7 +617,7 @@
         case 10:
 
             for (unsigned int i = 0; i < 10; i++, RK += 4) {
-                RK[4]  = RK[0] ^ RCON[i] ^
+                RK[4]  = RK[0] ^ round_constants[i] ^
                          ((uint32_t) FSb[MBEDTLS_BYTE_1(RK[3])]) ^
                          ((uint32_t) FSb[MBEDTLS_BYTE_2(RK[3])] <<  8) ^
                          ((uint32_t) FSb[MBEDTLS_BYTE_3(RK[3])] << 16) ^
@@ -641,7 +633,7 @@
         case 12:
 
             for (unsigned int i = 0; i < 8; i++, RK += 6) {
-                RK[6]  = RK[0] ^ RCON[i] ^
+                RK[6]  = RK[0] ^ round_constants[i] ^
                          ((uint32_t) FSb[MBEDTLS_BYTE_1(RK[5])]) ^
                          ((uint32_t) FSb[MBEDTLS_BYTE_2(RK[5])] <<  8) ^
                          ((uint32_t) FSb[MBEDTLS_BYTE_3(RK[5])] << 16) ^
@@ -658,7 +650,7 @@
         case 14:
 
             for (unsigned int i = 0; i < 7; i++, RK += 8) {
-                RK[8]  = RK[0] ^ RCON[i] ^
+                RK[8]  = RK[0] ^ round_constants[i] ^
                          ((uint32_t) FSb[MBEDTLS_BYTE_1(RK[7])]) ^
                          ((uint32_t) FSb[MBEDTLS_BYTE_2(RK[7])] <<  8) ^
                          ((uint32_t) FSb[MBEDTLS_BYTE_3(RK[7])] << 16) ^