diff --git a/ChangeLog b/ChangeLog
index 84938854e..acb26e492 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -5,6 +5,9 @@ mbed TLS ChangeLog (Sorted per branch, date)
 Bugfix
    * Add a check if iv_len is zero, and return an error if it is zero. reported
      by roberto. #716
+   * Replace preproccessor condition from #if defined(MBEDTLS_THREADING_PTHREAD)
+     to #if defined(MBEDTLS_THREADING_C) as the library cannot assume they will
+     always be implemented by pthread support. Fix for #696
 
 = mbed TLS 1.3.20 branch released 2017-06-21
 
diff --git a/library/x509_crt.c b/library/x509_crt.c
index 0bf4dea17..b6ca74cbd 100644
--- a/library/x509_crt.c
+++ b/library/x509_crt.c
@@ -1038,10 +1038,10 @@ int x509_crt_parse_path( x509_crt *chain, const char *path )
     if( dir == NULL )
         return( POLARSSL_ERR_X509_FILE_IO_ERROR );
 
-#if defined(POLARSSL_THREADING_PTHREAD)
+#if defined(POLARSSL_THREADING_C)
     if( ( ret = polarssl_mutex_lock( &readdir_mutex ) ) != 0 )
         return( ret );
-#endif
+#endif /* POLARSSL_THREADING_C */
 
     while( ( entry = readdir( dir ) ) != NULL )
     {
@@ -1068,10 +1068,10 @@ int x509_crt_parse_path( x509_crt *chain, const char *path )
     closedir( dir );
 
 cleanup:
-#if defined(POLARSSL_THREADING_PTHREAD)
+#if defined(POLARSSL_THREADING_C)
     if( polarssl_mutex_unlock( &readdir_mutex ) != 0 )
         ret = POLARSSL_ERR_THREADING_MUTEX_ERROR;
-#endif
+#endif /* POLARSSL_THREADING_C */
 
 #endif /* _WIN32 */