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Comment by fizixer | Hacker News Reader

I'm trying to get into refactoring (and even semantic analysis, and code-generation) for large C++ codebases using libclang, libtool, and the ilk.

Any guides to get started, and/or best practices?

Does it increase productivity by order of magnitude? (I'd like to think so. I think it's madness not to use any AST tool when working on large codebases).

Also I'm assuming "white-box" C/C++ tools like libclang/libtooling are much more powerful than black-box ones (like eclipse CDT), because of extensibility/programmability. Any comments, experiences?

what I'm trying to say is that a non-IDE but programmable editor (vim/emacs) combined with programmable libclang/libtooling, would trump a prepackaged IDE (like Visual Studio, Eclipse+CDT) by a wide margin. (of course there would be quite a bit of programming involved though).

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LibreOffice has a pile of clang plugins for analysing their huge and somewhat smelly C++ codebase. They've caught and repaired some horrible code with these. Pretty sure they ran iwyu over it as well.

howto: https://wiki.documentfoundation.org/Development/Clang_plugin...

code: http://cgit.freedesktop.org/libreoffice/core/tree/compilerpl...

I think you'll enjoy this talk: CppCon 2015: Atila Neves "Emacs as a C++ IDE" - https://m.youtube.com/watch?v=5FQwQ0QWBTU

Great talk.

So he created cmake-ide for emacs. I'm wondering is there an equivalent for make projects.

EDIT 1: The github page [1] says "It automatically detects Ninja and Make builds and sets the compile command accordingly". I'm wondering if that means make is fully supported.

[1] https://github.com/atilaneves/cmake-ide

The main feature that I miss from CLion is the ability to refactor. In CLion you can rename a class, and all of its usages, declarations, etc. will be renamed.

The most useful thing CLion can do is change the signature of a function, and its corresponding implementation and header declarations will be changed. So, you can rename a parameter and its declaration and implementation will be renamed for you, or you can delete a parameter, or change the type of a parameter, and CLion will change all its usages/definitions/declarations for you. All of this effects across all files in your project, so if you're in a .cpp file and you change the function signature, its declaration in the corresponding .h file will change as well.

(I believe you can do all of this in Eclipse as well)

Sadly I have yet to see a vim/emacs configuration that gets anywhere near the level of Eclipse/CLion.

>and all of its usages, declarations, etc. will be renamed.

Along with header include statements in any file that referenced the class - so say I refactored class Foo in include/mylib/foo.hpp and it's included in src/mylib/foo.cpp as <mylib/foo.hpp> - CLion happily "refactors" that to #include "foo.hpp" - spent the same ammount of time fixing this stuff as I would manually renaming use cases...

As a new IDE user, I was very excited about the language-aware "rename" refactoring ability. But I realized that the variables I rename are mostly badly chosen names in IDE code-generated boilerplate, i.e. names of widgets inserted into forms. When I'm writing new code in vim I just choose good names to begin with, so it's a bit of a wash for me.

I hope there is room in my brain to stay good at vim despite using VS at work.

Make yourself familiar with the sanitizer tools from gcc and clang (asan, ubsan, tsan, msam). They can help you find many types of bugs.

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