+.sp
+Note that this is different from fteqcc's __NULL__ in that gmqcc
+generates an actual empty global, rather than using the global at
+offset 0 because it would overlap with the global RETURN variable when
+dealing with vectors, which starts at offset 1. Setting a vector to
+__NULL__ in fteqcc causes only the vector's x component to be 0.
+However, its y and z components will contain the previous x and y
+components of the global OFS_RETURN.