Java™ Application Development on Linux - Dator

7.5 Options and Switches1857.5OPTIONS AND SWITCHESAs we have said, gcj is part of the gcc suite of compilers and therefore supportsall of the non-language-specific options and switches of that suite.As with most reference material in this book, we will only cover thehighlights. See the gcj manpage or the project’s Web site for full details. 14-IdirnameAdd dirname to the classpath ahead of its existing contents.-Dname[=value]Add name and optional value to the system properties list. This is onlyvalid with the --main switch.--mainSpecifies which class contains the application’s main(). This gives thestarting point for an application.-fno-bounds-checkDisable array bounds checking. Like “real” Java, gcj checks all array operationsto ensure that array bounds are not exceeded. Using this switchdisables that check. It speeds up array operations but can introduce subtleand hard-to-find bugs. Use at your own risk.-fno-store-checkLike -fno-bounds-check, this disables a safety feature on arrays. Normally,when you store an object into an array, a check is made to make surethat the object is assignment-compatible with the array type (in otherwords, that the object is an instanceof() of the array type). Using thisswitch disables this test. It speeds up array operations but can introducesubtle and hard-to-find bugs. Use at your own risk.There are other switches for native methods, bytecode (as opposed tonative) compilation, and some switches related to resources. We leave it as anexercise for the reader to learn and use these where needed.14. http://gcc.gnu.org/java/