fix type error in pthread_create, introduced with pthread_getattr_np
diff --git a/src/thread/pthread_create.c b/src/thread/pthread_create.c
index 6163f50..e6760ab 100644
--- a/src/thread/pthread_create.c
+++ b/src/thread/pthread_create.c
@@ -123,7 +123,7 @@
size_t need = libc.tls_size + __pthread_tsd_size;
size = attr._a_stacksize + DEFAULT_STACK_SIZE;
stack = (void *)(attr._a_stackaddr & -16);
- stack_limit = attr._a_stackaddr - size;
+ stack_limit = (void *)(attr._a_stackaddr - size);
/* Use application-provided stack for TLS only when
* it does not take more than ~12% or 2k of the
* application's stack space. */