Assembly language diff tool

I am not experienced in assembly language or compilers. But someone asked me if you could do a comparison of the low level assembly code, see where changes have been made, and correlate that to changes made elsewhere. Basically we have a software provider that gave us newly compiled software that works better than the previous version in eliminating bugs, but we do not know why the bugs are not there and don't want it popping up again. We have been trying to track down the issue looking at our own code and theirs (we 开发者_JAVA技巧do not know where the error lies), but with a newly compiled version of their code (they changed the optimization settings in how they compile the code), things work. Sorry for the somewhat abstract question.

It will be practically impossible to tell the difference between the new and old code if it's of any appreciable size. There will be a HUGE amount of differences, especially it it was compiled on a different optimization level. You could manually try to look through the functions that were giving problems before to compare. If you don't know much assembly (like me :) ) it will be tough going. If you only have the executable, you can use a dumping utility like dumpbin.exe or objdump to see the assembly.