Re: How to look up where a structure is defined?

[Konstantin Kharlamov <hi-angel@yandex.ru>]

On Wed, 2021-03-03 at 08:12 -0600, Peng Yu via Libc-help wrote:
> Hi,
> 
> I would like to lookup types and constants in libc. It would be most
> efficient to have a database lookup for this purpose instead of using
> google search or code search.
> 
> Is there such a database available? Thanks.
> 

I assume you're referring to the usual "go to definition" functional in code editors/IDE. In that case I don't think glibc is too different from other projects. The simplest (but not very good) way is using Universal Ctags, and generating a tags file from the source tree, and then feeding that into your editor/IDE. I don't know if it's good enough for you: it should work for basic navigation, but wouldn't provide you with navigation inside functions, or for various complex constructions out of macros.

Nowadays most popular way is lsp-server, should be supported by most existing modern IDEs/editors, including vim/emacs (you might need to install a plugin). For C/C++ projects I usually use `clangd` as the lsp-server. You'll stumble upon a gotcha though: Glibc is a very old project, that is still using autotools/make. So, unlike Meson-based projects, you'll need to generate `compile_commands.json` file yourself. It should be easy though: there's `bear` utility, which takes a make command as input, and parses it output while it builds the project, and stores the output into `compile_commands.json` file. So for example: if you usually build glibc with `make`, then to generate the file you have to use a `bear -- make` instead.