diff --git a/gcc/ada/libgnarl/s-osinte__rtems.ads b/gcc/ada/libgnarl/s-osinte__rtems.ads
index 5743a6aa468..9a0561fccd1 100644
--- a/gcc/ada/libgnarl/s-osinte__rtems.ads
+++ b/gcc/ada/libgnarl/s-osinte__rtems.ads
@@ -585,7 +585,7 @@ package System.OS_Interface is
 
 private
 
-   type sigset_t is new int;
+   type sigset_t is new unsigned_long;
 
    type pid_t is new int;