Bugfix * Failures of alternative implementations of AES or DES single-block functions enabled with MBEDTLS_AES_ENCRYPT_ALT, MBEDTLS_AES_DECRYPT_ALT, MBEDTLS_DES_CRYPT_ECB_ALT or MBEDTLS_DES3_CRYPT_ECB_ALT were ignored. This does not concern the implementation provided with Mbed TLS, where this function cannot fail, or full-module replacements with MBEDTLS_AES_ALT or MBEDTLS_DES_ALT. Reported by Armelle Duboc in #1092. Changes * Warn if errors from AES or DES functions are ignored. This is currently supported on GCC-like compilers and on MSVC and can be configured by setting MBEDTLS_CHECK_RETURN in config.h.