diff --git a/src/h/ecl-atomic-ops.h b/src/h/ecl-atomic-ops.h
index 9fca5f883..af4170454 100644
--- a/src/h/ecl-atomic-ops.h
+++ b/src/h/ecl-atomic-ops.h
@@ -28,7 +28,7 @@
 #else
 # define AO_load(x) (x)
 # define AO_store(x,y) ((x)=(y))
-# define AO_nop_full(x,y)
+# define AO_nop_full()
 #endif
 
 #endif /* ECL_ATOMIC_OPS_H */
diff --git a/src/h/stack-resize.h b/src/h/stack-resize.h
index cf14e4646..5c4e926a6 100644
--- a/src/h/stack-resize.h
+++ b/src/h/stack-resize.h
@@ -23,21 +23,21 @@
  * via mprotect(), so we have to use sigprocmask instead. No
  * performance problems, since this is only used for stack
  * resizing. */
-#ifdef ECL_USE_MPROTECT
-#ifdef HAVE_SIGPROCMASK
-#include <signal.h>
-#define ECL_STACK_RESIZE_DISABLE_INTERRUPTS(the_env) \
-    sigset_t __sigset_new, __sigset_previous;    \
-    sigfillset(&__sigset_new);                   \
-    pthread_sigmask(SIG_BLOCK, &__sigset_new, &__sigset_previous)
-#define ECL_STACK_RESIZE_ENABLE_INTERRUPTS(the_env) \
-    pthread_sigmask(SIG_SETMASK, &__sigset_previous, NULL)
+#if defined(ECL_THREADS) && defined(ECL_USE_MPROTECT)
+# ifdef HAVE_SIGPROCMASK
+#  include <signal.h>
+#  define ECL_STACK_RESIZE_DISABLE_INTERRUPTS(the_env) \
+        sigset_t __sigset_new, __sigset_previous;      \
+        sigfillset(&__sigset_new);                     \
+        pthread_sigmask(SIG_BLOCK, &__sigset_new, &__sigset_previous)
+#  define ECL_STACK_RESIZE_ENABLE_INTERRUPTS(the_env) \
+        pthread_sigmask(SIG_SETMASK, &__sigset_previous, NULL)
+# else
+#  error "Can't protect stack resizing from interrupts without sigprocmask. Either build ECL without mprotect() or live with possible race conditions."
+# endif  /* HAVE_SIGPROCMASK */
 #else
-#error "Can't protect stack resizing from interrupts without sigprocmask. Either build ECL without mprotect() or live with possible race conditions."
-#endif  /* HAVE_SIGPROCMASK */
-#else
-#define ECL_STACK_RESIZE_DISABLE_INTERRUPTS(the_env) ecl_disable_interrupts_env(the_env);
-#define ECL_STACK_RESIZE_ENABLE_INTERRUPTS(the_env) ecl_enable_interrupts_env(env);
-#endif  /* ECL_USE_MPROTECT */
+# define ECL_STACK_RESIZE_DISABLE_INTERRUPTS(the_env) ecl_disable_interrupts_env(the_env);
+# define ECL_STACK_RESIZE_ENABLE_INTERRUPTS(the_env) ecl_enable_interrupts_env(env);
+# endif  /* ECL_THREADS && ECL_USE_MPROTECT */
 
 #endif  /* ECL_STACK_RESIZE_H */