PURPOSE: To obtain a compiler which produces selectively the different object codes in response to two operating systems, by adding the slight processing to a comparatively limited part of the compiler.

CONSTITUTION: A compiler produces an intermediate code 13 which produces an argument list and an intermediate code 14 which calls an external program that designated said argument list as an operand at an analysis processing part 2 in a translation process to call an external program containing a CALL sentence of a source program 10, etc. An object program production part 20 produces an object code 17 for production of an argument list from the code 13 and discriminating the designation for need of use of a stack in the process of the code 14. Thus the part 20 produces the object codes 18 and 19 when no stack is used and then an object code 23 to load all contents addresses of the argument list produced by the code 17 into a stack as well as an object code 24 to branch said addresses to the external program when the use of the stack is designated.