GuestLog in

For a long time goldroad's ARM assembler has been the only assembler available to GBA hackers. Unfortunately, it is plagued by some bugs and usability problems. It was clearly not designed with ROM hackers in mind, so for example there is no option to assemble code directly into a ROM image. The bugs mostly consist of not detecting out of range errors. If your code becomes so long that symbols get pushed outside of their range, the assembler will not notice and tell you instead that everything went fine. Have fun fixing the supposedly inexplicable bugs in your hack later on.

Fortunately there are alternatives by now, both already released and in the making. byuu's latest xkas rewrite for example supports multiple CPUs now. A THUMB module should be available soon. Another alternative if you have the program is to use no$GBA's internal assembler.