Rename identifiers containing double-underscore

Rename identifiers containing double-underscore (`__`) to avoid `__`.
The reason to avoid double-underscore is that all identifiers
containing double-underscore are reserved in C++. Rename all such
identifiers that appear in any public header, including ssl_internal.h
which is in principle private but in practice is installed with the
public headers.

This commit makes check-names.sh pass.

```
perl -i -pe 's/\bMBEDTLS_SSL__ECP_RESTARTABLE\b/MBEDTLS_SSL_ECP_RESTARTABLE_ENABLED/g; s/\bMBEDTLS_KEY_EXCHANGE_(_\w+)_(_\w+)\b/MBEDTLS_KEY_EXCHANGE${1}${2}/g' include/mbedtls/*.h library/*.c programs/*/*.c scripts/data_files/rename-1.3-2.0.txt tests/suites/*.function
```
diff --git a/include/mbedtls/check_config.h b/include/mbedtls/check_config.h
index f98f494..d904d5a 100644
--- a/include/mbedtls/check_config.h
+++ b/include/mbedtls/check_config.h
@@ -292,7 +292,7 @@
 #error "MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED defined, but not all prerequisites"
 #endif
 
-#if defined(MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED) &&        \
+#if defined(MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED) &&        \
     !defined(MBEDTLS_SSL_KEEP_PEER_CERTIFICATE) &&              \
     ( !defined(MBEDTLS_SHA256_C) &&                             \
       !defined(MBEDTLS_SHA512_C) &&                             \
diff --git a/include/mbedtls/compat-1.3.h b/include/mbedtls/compat-1.3.h
index 361cf56..b268734 100644
--- a/include/mbedtls/compat-1.3.h
+++ b/include/mbedtls/compat-1.3.h
@@ -1250,9 +1250,9 @@
 #define POLARSSL_KEY_EXCHANGE_PSK MBEDTLS_KEY_EXCHANGE_PSK
 #define POLARSSL_KEY_EXCHANGE_RSA MBEDTLS_KEY_EXCHANGE_RSA
 #define POLARSSL_KEY_EXCHANGE_RSA_PSK MBEDTLS_KEY_EXCHANGE_RSA_PSK
-#define POLARSSL_KEY_EXCHANGE__SOME__ECDHE_ENABLED MBEDTLS_KEY_EXCHANGE__SOME__ECDHE_ENABLED
-#define POLARSSL_KEY_EXCHANGE__SOME__PSK_ENABLED MBEDTLS_KEY_EXCHANGE__SOME__PSK_ENABLED
-#define POLARSSL_KEY_EXCHANGE__WITH_CERT__ENABLED MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED
+#define POLARSSL_KEY_EXCHANGE__SOME__ECDHE_ENABLED MBEDTLS_KEY_EXCHANGE_SOME_ECDHE_ENABLED
+#define POLARSSL_KEY_EXCHANGE__SOME__PSK_ENABLED MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED
+#define POLARSSL_KEY_EXCHANGE__WITH_CERT__ENABLED MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED
 #define POLARSSL_KEY_LENGTH_DES MBEDTLS_KEY_LENGTH_DES
 #define POLARSSL_KEY_LENGTH_DES_EDE MBEDTLS_KEY_LENGTH_DES_EDE
 #define POLARSSL_KEY_LENGTH_DES_EDE3 MBEDTLS_KEY_LENGTH_DES_EDE3
diff --git a/include/mbedtls/ssl.h b/include/mbedtls/ssl.h
index 1666f8c..e93e8f3 100644
--- a/include/mbedtls/ssl.h
+++ b/include/mbedtls/ssl.h
@@ -825,7 +825,7 @@
 typedef void mbedtls_ssl_async_cancel_t( mbedtls_ssl_context *ssl );
 #endif /* MBEDTLS_SSL_ASYNC_PRIVATE */
 
-#if defined(MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED) &&        \
+#if defined(MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED) &&        \
     !defined(MBEDTLS_SSL_KEEP_PEER_CERTIFICATE)
 #define MBEDTLS_SSL_PEER_CERT_DIGEST_MAX_LEN  48
 #if defined(MBEDTLS_SHA256_C)
@@ -841,7 +841,7 @@
 /* This is already checked in check_config.h, but be sure. */
 #error "Bad configuration - need SHA-1, SHA-256 or SHA-512 enabled to compute digest of peer CRT."
 #endif
-#endif /* MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED &&
+#endif /* MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED &&
           !MBEDTLS_SSL_KEEP_PEER_CERTIFICATE */
 
 /*
@@ -937,7 +937,7 @@
     void *p_vrfy;                   /*!< context for X.509 verify calllback */
 #endif
 
-#if defined(MBEDTLS_KEY_EXCHANGE__SOME__PSK_ENABLED)
+#if defined(MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED)
     /** Callback to retrieve PSK key from identity                          */
     int (*f_psk)(void *, mbedtls_ssl_context *, const unsigned char *, size_t);
     void *p_psk;                    /*!< context for PSK callback           */
@@ -1000,7 +1000,7 @@
     void *p_async_config_data; /*!< Configuration data set by mbedtls_ssl_conf_async_private_cb(). */
 #endif /* MBEDTLS_SSL_ASYNC_PRIVATE */
 
-#if defined(MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED)
+#if defined(MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED)
     const int *sig_hashes;          /*!< allowed signature hashes           */
 #endif
 
@@ -1013,7 +1013,7 @@
     mbedtls_mpi dhm_G;              /*!< generator for DHM                  */
 #endif
 
-#if defined(MBEDTLS_KEY_EXCHANGE__SOME__PSK_ENABLED)
+#if defined(MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED)
 
 #if defined(MBEDTLS_USE_PSA_CRYPTO)
     psa_key_handle_t psk_opaque; /*!< PSA key slot holding opaque PSK.
@@ -1044,7 +1044,7 @@
                                      *   Its value is non-zero if and only if
                                      *   \c psk is not \c NULL or \c psk_opaque
                                      *   is not \c 0. */
-#endif /* MBEDTLS_KEY_EXCHANGE__SOME__PSK_ENABLED */
+#endif /* MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED */
 
 #if defined(MBEDTLS_SSL_ALPN)
     const char **alpn_list;         /*!< ordered list of protocols          */
@@ -2668,7 +2668,7 @@
                               mbedtls_pk_context *pk_key );
 #endif /* MBEDTLS_X509_CRT_PARSE_C */
 
-#if defined(MBEDTLS_KEY_EXCHANGE__SOME__PSK_ENABLED)
+#if defined(MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED)
 /**
  * \brief          Configure a pre-shared key (PSK) and identity
  *                 to be used in PSK-based ciphersuites.
@@ -2815,7 +2815,7 @@
                      int (*f_psk)(void *, mbedtls_ssl_context *, const unsigned char *,
                                   size_t),
                      void *p_psk );
-#endif /* MBEDTLS_KEY_EXCHANGE__SOME__PSK_ENABLED */
+#endif /* MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED */
 
 #if defined(MBEDTLS_DHM_C) && defined(MBEDTLS_SSL_SRV_C)
 
@@ -2920,7 +2920,7 @@
                               const mbedtls_ecp_group_id *curves );
 #endif /* MBEDTLS_ECP_C */
 
-#if defined(MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED)
+#if defined(MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED)
 /**
  * \brief          Set the allowed hashes for signatures during the handshake.
  *                 (Default: all available hashes except MD5.)
@@ -2941,7 +2941,7 @@
  */
 void mbedtls_ssl_conf_sig_hashes( mbedtls_ssl_config *conf,
                                   const int *hashes );
-#endif /* MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED */
+#endif /* MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED */
 
 #if defined(MBEDTLS_X509_CRT_PARSE_C)
 /**
diff --git a/include/mbedtls/ssl_ciphersuites.h b/include/mbedtls/ssl_ciphersuites.h
index 5505e52..7fbafa4 100644
--- a/include/mbedtls/ssl_ciphersuites.h
+++ b/include/mbedtls/ssl_ciphersuites.h
@@ -312,7 +312,7 @@
     defined(MBEDTLS_KEY_EXCHANGE_RSA_PSK_ENABLED)       || \
     defined(MBEDTLS_KEY_EXCHANGE_ECDH_RSA_ENABLED)      || \
     defined(MBEDTLS_KEY_EXCHANGE_ECDH_ECDSA_ENABLED)
-#define MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED
+#define MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED
 #endif
 
 /* Key exchanges allowing client certificate requests */
@@ -322,28 +322,28 @@
     defined(MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED)     ||       \
     defined(MBEDTLS_KEY_EXCHANGE_ECDH_ECDSA_ENABLED)    ||       \
     defined(MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED)
-#define MBEDTLS_KEY_EXCHANGE__CERT_REQ_ALLOWED__ENABLED
+#define MBEDTLS_KEY_EXCHANGE_CERT_REQ_ALLOWED_ENABLED
 #endif
 
 /* Key exchanges involving server signature in ServerKeyExchange */
 #if defined(MBEDTLS_KEY_EXCHANGE_DHE_RSA_ENABLED)       || \
     defined(MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED)     || \
     defined(MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED)
-#define MBEDTLS_KEY_EXCHANGE__WITH_SERVER_SIGNATURE__ENABLED
+#define MBEDTLS_KEY_EXCHANGE_WITH_SERVER_SIGNATURE_ENABLED
 #endif
 
 /* Key exchanges using ECDH */
 #if defined(MBEDTLS_KEY_EXCHANGE_ECDH_RSA_ENABLED)      || \
     defined(MBEDTLS_KEY_EXCHANGE_ECDH_ECDSA_ENABLED)
-#define MBEDTLS_KEY_EXCHANGE__SOME__ECDH_ENABLED
+#define MBEDTLS_KEY_EXCHANGE_SOME_ECDH_ENABLED
 #endif
 
 /* Key exchanges that don't involve ephemeral keys */
 #if defined(MBEDTLS_KEY_EXCHANGE_RSA_ENABLED)           || \
     defined(MBEDTLS_KEY_EXCHANGE_PSK_ENABLED)           || \
     defined(MBEDTLS_KEY_EXCHANGE_RSA_PSK_ENABLED)       || \
-    defined(MBEDTLS_KEY_EXCHANGE__SOME__ECDH_ENABLED)
-#define MBEDTLS_KEY_EXCHANGE__SOME_NON_PFS__ENABLED
+    defined(MBEDTLS_KEY_EXCHANGE_SOME_ECDH_ENABLED)
+#define MBEDTLS_KEY_EXCHANGE_SOME_NON_PFS_ENABLED
 #endif
 
 /* Key exchanges that involve ephemeral keys */
@@ -353,7 +353,7 @@
     defined(MBEDTLS_KEY_EXCHANGE_ECDHE_PSK_ENABLED)     || \
     defined(MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED)   || \
     defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED)
-#define MBEDTLS_KEY_EXCHANGE__SOME_PFS__ENABLED
+#define MBEDTLS_KEY_EXCHANGE_SOME_PFS_ENABLED
 #endif
 
 /* Key exchanges using a PSK */
@@ -361,20 +361,20 @@
     defined(MBEDTLS_KEY_EXCHANGE_RSA_PSK_ENABLED)       || \
     defined(MBEDTLS_KEY_EXCHANGE_DHE_PSK_ENABLED)       || \
     defined(MBEDTLS_KEY_EXCHANGE_ECDHE_PSK_ENABLED)
-#define MBEDTLS_KEY_EXCHANGE__SOME__PSK_ENABLED
+#define MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED
 #endif
 
 /* Key exchanges using DHE */
 #if defined(MBEDTLS_KEY_EXCHANGE_DHE_RSA_ENABLED)       || \
     defined(MBEDTLS_KEY_EXCHANGE_DHE_PSK_ENABLED)
-#define MBEDTLS_KEY_EXCHANGE__SOME__DHE_ENABLED
+#define MBEDTLS_KEY_EXCHANGE_SOME_DHE_ENABLED
 #endif
 
 /* Key exchanges using ECDHE */
 #if defined(MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED)     || \
     defined(MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED)   || \
     defined(MBEDTLS_KEY_EXCHANGE_ECDHE_PSK_ENABLED)
-#define MBEDTLS_KEY_EXCHANGE__SOME__ECDHE_ENABLED
+#define MBEDTLS_KEY_EXCHANGE_SOME_ECDHE_ENABLED
 #endif
 
 typedef struct mbedtls_ssl_ciphersuite_t mbedtls_ssl_ciphersuite_t;
@@ -417,7 +417,7 @@
 int mbedtls_ssl_ciphersuite_uses_ec( const mbedtls_ssl_ciphersuite_t *info );
 int mbedtls_ssl_ciphersuite_uses_psk( const mbedtls_ssl_ciphersuite_t *info );
 
-#if defined(MBEDTLS_KEY_EXCHANGE__SOME_PFS__ENABLED)
+#if defined(MBEDTLS_KEY_EXCHANGE_SOME_PFS_ENABLED)
 static inline int mbedtls_ssl_ciphersuite_has_pfs( const mbedtls_ssl_ciphersuite_t *info )
 {
     switch( info->key_exchange )
@@ -434,9 +434,9 @@
             return( 0 );
     }
 }
-#endif /* MBEDTLS_KEY_EXCHANGE__SOME_PFS__ENABLED */
+#endif /* MBEDTLS_KEY_EXCHANGE_SOME_PFS_ENABLED */
 
-#if defined(MBEDTLS_KEY_EXCHANGE__SOME_NON_PFS__ENABLED)
+#if defined(MBEDTLS_KEY_EXCHANGE_SOME_NON_PFS_ENABLED)
 static inline int mbedtls_ssl_ciphersuite_no_pfs( const mbedtls_ssl_ciphersuite_t *info )
 {
     switch( info->key_exchange )
@@ -452,9 +452,9 @@
             return( 0 );
     }
 }
-#endif /* MBEDTLS_KEY_EXCHANGE__SOME_NON_PFS__ENABLED */
+#endif /* MBEDTLS_KEY_EXCHANGE_SOME_NON_PFS_ENABLED */
 
-#if defined(MBEDTLS_KEY_EXCHANGE__SOME__ECDH_ENABLED)
+#if defined(MBEDTLS_KEY_EXCHANGE_SOME_ECDH_ENABLED)
 static inline int mbedtls_ssl_ciphersuite_uses_ecdh( const mbedtls_ssl_ciphersuite_t *info )
 {
     switch( info->key_exchange )
@@ -467,7 +467,7 @@
             return( 0 );
     }
 }
-#endif /* MBEDTLS_KEY_EXCHANGE__SOME__ECDH_ENABLED */
+#endif /* MBEDTLS_KEY_EXCHANGE_SOME_ECDH_ENABLED */
 
 static inline int mbedtls_ssl_ciphersuite_cert_req_allowed( const mbedtls_ssl_ciphersuite_t *info )
 {
@@ -504,7 +504,7 @@
     }
 }
 
-#if defined(MBEDTLS_KEY_EXCHANGE__SOME__DHE_ENABLED)
+#if defined(MBEDTLS_KEY_EXCHANGE_SOME_DHE_ENABLED)
 static inline int mbedtls_ssl_ciphersuite_uses_dhe( const mbedtls_ssl_ciphersuite_t *info )
 {
     switch( info->key_exchange )
@@ -517,9 +517,9 @@
             return( 0 );
     }
 }
-#endif /* MBEDTLS_KEY_EXCHANGE__SOME__DHE_ENABLED) */
+#endif /* MBEDTLS_KEY_EXCHANGE_SOME_DHE_ENABLED) */
 
-#if defined(MBEDTLS_KEY_EXCHANGE__SOME__ECDHE_ENABLED)
+#if defined(MBEDTLS_KEY_EXCHANGE_SOME_ECDHE_ENABLED)
 static inline int mbedtls_ssl_ciphersuite_uses_ecdhe( const mbedtls_ssl_ciphersuite_t *info )
 {
     switch( info->key_exchange )
@@ -533,9 +533,9 @@
             return( 0 );
     }
 }
-#endif /* MBEDTLS_KEY_EXCHANGE__SOME__ECDHE_ENABLED) */
+#endif /* MBEDTLS_KEY_EXCHANGE_SOME_ECDHE_ENABLED) */
 
-#if defined(MBEDTLS_KEY_EXCHANGE__WITH_SERVER_SIGNATURE__ENABLED)
+#if defined(MBEDTLS_KEY_EXCHANGE_WITH_SERVER_SIGNATURE_ENABLED)
 static inline int mbedtls_ssl_ciphersuite_uses_server_signature( const mbedtls_ssl_ciphersuite_t *info )
 {
     switch( info->key_exchange )
@@ -549,7 +549,7 @@
             return( 0 );
     }
 }
-#endif /* MBEDTLS_KEY_EXCHANGE__WITH_SERVER_SIGNATURE__ENABLED */
+#endif /* MBEDTLS_KEY_EXCHANGE_WITH_SERVER_SIGNATURE_ENABLED */
 
 #ifdef __cplusplus
 }
diff --git a/include/mbedtls/ssl_internal.h b/include/mbedtls/ssl_internal.h
index 6332d14..7122b2b 100644
--- a/include/mbedtls/ssl_internal.h
+++ b/include/mbedtls/ssl_internal.h
@@ -113,7 +113,7 @@
     defined(MBEDTLS_SSL_CLI_C) && \
     defined(MBEDTLS_SSL_PROTO_TLS1_2) && \
     defined(MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED)
-#define MBEDTLS_SSL__ECP_RESTARTABLE
+#define MBEDTLS_SSL_ECP_RESTARTABLE_ENABLED
 #endif
 
 #define MBEDTLS_SSL_INITIAL_HANDSHAKE           0
@@ -278,7 +278,7 @@
 #endif
 
 #if defined(MBEDTLS_SSL_PROTO_TLS1_2) && \
-    defined(MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED)
+    defined(MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED)
 /*
  * Abstraction for a grid of allowed signature-hash-algorithm pairs.
  */
@@ -293,7 +293,7 @@
     mbedtls_md_type_t ecdsa;
 };
 #endif /* MBEDTLS_SSL_PROTO_TLS1_2 &&
-          MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED */
+          MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED */
 
 typedef int  mbedtls_ssl_tls_prf_cb( const unsigned char *secret, size_t slen,
                                      const char *label,
@@ -309,7 +309,7 @@
      */
 
 #if defined(MBEDTLS_SSL_PROTO_TLS1_2) && \
-    defined(MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED)
+    defined(MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED)
     mbedtls_ssl_sig_hash_set_t hash_algs;             /*!<  Set of suitable sig-hash pairs */
 #endif
 #if defined(MBEDTLS_DHM_C)
@@ -338,13 +338,13 @@
     defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED)
     const mbedtls_ecp_curve_info **curves;      /*!<  Supported elliptic curves */
 #endif
-#if defined(MBEDTLS_KEY_EXCHANGE__SOME__PSK_ENABLED)
+#if defined(MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED)
 #if defined(MBEDTLS_USE_PSA_CRYPTO)
     psa_key_handle_t psk_opaque;        /*!< Opaque PSK from the callback   */
 #endif /* MBEDTLS_USE_PSA_CRYPTO */
     unsigned char *psk;                 /*!<  PSK from the callback         */
     size_t psk_len;                     /*!<  Length of PSK from callback   */
-#endif /* MBEDTLS_KEY_EXCHANGE__SOME__PSK_ENABLED */
+#endif /* MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED */
 #if defined(MBEDTLS_X509_CRT_PARSE_C)
     mbedtls_ssl_key_cert *key_cert;     /*!< chosen key/cert pair (server)  */
 #if defined(MBEDTLS_SSL_SERVER_NAME_INDICATION)
@@ -354,7 +354,7 @@
     mbedtls_x509_crl *sni_ca_crl;       /*!< trusted CAs CRLs from SNI      */
 #endif /* MBEDTLS_SSL_SERVER_NAME_INDICATION */
 #endif /* MBEDTLS_X509_CRT_PARSE_C */
-#if defined(MBEDTLS_SSL__ECP_RESTARTABLE)
+#if defined(MBEDTLS_SSL_ECP_RESTARTABLE_ENABLED)
     int ecrs_enabled;                   /*!< Handshake supports EC restart? */
     mbedtls_x509_crt_restart_ctx ecrs_ctx;  /*!< restart context            */
     enum { /* this complements ssl->state with info on intra-state operations */
@@ -746,7 +746,7 @@
 #endif /* MBEDTLS_SSL_PROTO_DTLS */
 
 #if defined(MBEDTLS_SSL_PROTO_TLS1_2) && \
-    defined(MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED)
+    defined(MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED)
 
 /* Find an entry in a signature-hash set matching a given hash algorithm. */
 mbedtls_md_type_t mbedtls_ssl_sig_hash_set_find( mbedtls_ssl_sig_hash_set_t *set,
@@ -766,7 +766,7 @@
 }
 
 #endif /* MBEDTLS_SSL_PROTO_TLS1_2) &&
-          MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED */
+          MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED */
 
 /**
  * \brief           Free referenced items in an SSL transform context and clear
@@ -893,7 +893,7 @@
 void mbedtls_ssl_optimize_checksum( mbedtls_ssl_context *ssl,
                             const mbedtls_ssl_ciphersuite_t *ciphersuite_info );
 
-#if defined(MBEDTLS_KEY_EXCHANGE__SOME__PSK_ENABLED)
+#if defined(MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED)
 int mbedtls_ssl_psk_derive_premaster( mbedtls_ssl_context *ssl, mbedtls_key_exchange_type_t key_ex );
 #endif
 
@@ -911,7 +911,7 @@
 int mbedtls_ssl_check_curve( const mbedtls_ssl_context *ssl, mbedtls_ecp_group_id grp_id );
 #endif
 
-#if defined(MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED)
+#if defined(MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED)
 int mbedtls_ssl_check_sig_hash( const mbedtls_ssl_context *ssl,
                                 mbedtls_md_type_t md );
 #endif