fix compilation errors related to C specifics

tests/simple.c

@@ -0,0 +1,16 @@
+#include <stdio.h>
+
+void do_stuff(int my_arg)
+{
+    int my_local = my_arg + 2;
+    int i;
+
+    for (i = 0; i < my_local; ++i)
+        printf("i = %d\n", i);
+}
+
+int main()
+{
+    do_stuff(2);
+    return 0;
+}