PURPOSE: To easily execute work due to a change in the management of an argument at the time of developing a software product.

CONSTITUTION: An argument management information extracting means 4 in an electronic computer system 3 inputs a source program 2 from a source library 1 and extracts argument management information such as an argument, a function name and a function access position corresponding to the program 2. An argument management table formation managing means 5 stores the extracted argument management information in an argument management table 9 formed in an external storage device 8. At the time of the storage, the means 5 executes the generation management of the formed table 9. When the up-to-date argument management table 9 and a pregeneration argument management table for preceding generation are stored in the device 8, an argument management table changing information extracting means 6 extracts a difference between both the tables 9, 10 as change information. The extracted change information is edited and outputted to an output device 11 by a change information output means 7.