Uncrustify proposes the following patch: --- a/core/thread.c +++ b/core/thread.c @@ -239,8 +239,8 @@ kernel_pid_t thread_create(char *stack, int stacksize, uint8_t priority, * Make sure the TLS area is aligned as required and that the * resulting stack will also be aligned as required */ - thread->tls = (void *) ((uintptr_t) tls & ~ (TLS_ALIGN - 1)); - stacksize = (char *) thread->tls - stack; + thread->tls = (void *)((uintptr_t)tls & ~(TLS_ALIGN - 1)); + stacksize = (char *)thread->tls - stack; _init_tls(thread->tls); #endif