diff --git a/components/libc/compilers/armlibc/stubs.c b/components/libc/compilers/armlibc/stubs.c
index 600100c554..a4879be0c6 100644
--- a/components/libc/compilers/armlibc/stubs.c
+++ b/components/libc/compilers/armlibc/stubs.c
@@ -270,6 +270,8 @@ RT_WEAK void _sys_exit(int return_code)
         rt_thread_suspend(self);
         rt_schedule();
     }
+
+    while(1); /* noreturn */
 }
 
 /**
diff --git a/components/libc/compilers/newlib/syscalls.c b/components/libc/compilers/newlib/syscalls.c
index 5ce2df284d..a0a081bd26 100644
--- a/components/libc/compilers/newlib/syscalls.c
+++ b/components/libc/compilers/newlib/syscalls.c
@@ -303,6 +303,8 @@ exit (int status)
         rt_thread_suspend(self);
         rt_schedule();
     }
+
+    while(1); /* noreturn */
 }
 
 void
@@ -334,6 +336,8 @@ void abort(void)
         rt_thread_suspend(self);
         rt_schedule();
     }
+
+    while(1); /* noreturn */
 }
 
 uid_t getuid(void)