Category: Programming

The gcc compiler has always worked by writing out assembly code in text format. The assembler reads this text file to produce an object file. Most compilers work this way, although there have been some exceptions such as the MIPS compiler used on Irix. Clearly this process of producing text and then parsing it again…

Languages that support exceptions need to support destructors or they need to support a try/finally construct. Otherwise using exceptions is too difficult, because if you have some local state to clean up in a function, you have to catch and rethrow every exception. The goal of exceptions in C++ is that code which does not…

Although I can’t find it now, I think it was Dan Bernstein who said somewhere that programs should avoid syntax when possible. Using syntax means permitting syntax errors. Avoiding syntax means making syntax errors impossible. Even if it wasn’t Bernstein who said this, you can see the idea in action in things like his tinydns…

GCC’s inline assembler syntax is very powerful and is the best mechanism I know of to mix assembly code and optimized C/C++ code. It lets you take advantage of assembly features like add-with-carry or direct calls into the kernel without losing optimizations. I don’t know of any other approach which supports that. That said, the…

Many programs these days are written using multiple threads, multiple processes, and multiple languages. Our current debugging solutions don’t cope particularly well with any of those. gdb supports multiple threads. However, the interface is hard to work with. You have to select which thread you want to look at. Threads are referred to using numbers…