Jun 08

Pork 0.9 in the wild

Those who would like to play with Pork, but are allergic to pulling sources from version control can now download an actual pork release. Now someone needs to hook this into a GUI to provide easy Eclipse-style refactoring for C++.

Jun 08

Status Report: Nearterm plans for Pork, Dehydra


I planned to release Pork 1.0 for a while now. The tools work great, even if all the love is going to the GCC-based toolchain. However, after hearing grumpy comments from a certain coworker about the uglyness of the oink build system it dawned on me that it’s rather mean to release such a mess and call it 1.0.

So I think I’ll release Pork 0.9 in the current state, so I can focus on near term GCC toolchain work. Pork in the current form means oink stack + my refactoring tools + changes to elsa and other libs to support C/C++ refactoring needs.

This will be followed up by Pork 1.0. 1.0 will involve changes to the build system to get rid of oink(we only use the oink build system and rarely use oink API). To put this another way: I don’t expect any functionality changes between 0.9 and 1.0 other than an improved build system to make it easier to get started with writing new tools.

Pork – Future

I am pretty happy with Pork as it is. I think we’ve taken Elsa as far as it’ll let us go. The only realistic improvement on the Pork side may be to have Dehydra generate a JS binding to Elsa’s extensive AST to make rewriting stuff easier. However, I’m not sure if that’s worth the effort nor that a C++ AST will reflect into JavaScript as well as GCC GIMPLE.


On the other hand, something needs to be done about the main ingradient that makes Pork tick: MCPP. MCPP does a lovely job of annotating what the C preprocessor is doing, but configuring GCC to use a foreign preprocessor is a giant hassle and making sure it works correctly is troublesome. At the GCC summit, Tom gave me an idea on how similar functionality can be added to GCC directly by extending the include backtrace with macro expansions. Not only would such integration simplify Pork setup and increase Pork’s operating speed, but it is also a clean way to expose preprocessor constructs to the AST presented in De/Treehydra. It should allow for more preprocessor awareness directly in analysis stage of refactoring instead of only in the final rewriting stage as is currently done. As a side-effect, GCC would gain better error messages too.

So while this isn’t going to affect Pork directly, it will simplify the lives of Pork users while opening new analysis frontiers. Even though I hate working on preprocessor stuff, I think this work will need to happen sometime in the near future.

The Hydras

Dehydra 0.9 has been out for a while, I planned to release 1.0 soon after unless there are major flaws discovered in the API. The situation changed at the GCC summit. The fact that FSF reversed their stance on GCC plugins means that we should be concentrating on getting the plugin stuff reviewed.

So in the near term I’m forward porting the plugin stuff to trunk GCC, then I’ll be generalize the plugin API to suit at least one other GCC plugin user that we met with at the summit. The downside is that I don’t want to release Dehydra 1.0 and immediately break the plugin API. The upside is that the new API should be more general and more minimalistic and will likely be close to what will eventually become an official plugin API.

Summary: In my mind Dehydra and Pork are 1.0 quality, but I want to future-proof them a little bit before calling them 1.0.

Jun 08

GCC Summit

Our presentation on Treehydra and Dehydra GCC plugins was received well at the summit.

The big news is that FSF is working on license changes to allow GPL-only GCC plugins. I’m looking forward to having our work be compatible with future GCC without any patching.

In a few minutes we’ll be having a meeting with users of other plugin frameworks to have an initial discussion on a common API. I’m working on forward porting my patches, so they can start getting reviewed ahead of license changes.

Jun 08

Dehydra 0.9: It’s alive!

I am finally happy enough with Dehydra API and functionality to release 0.9. Dehydra is basically feature complete, the main reason I’m not calling it 1.0 is in case there are outstanding API bugs.

I believe Dehydra is the first useful open source static analysis tool. I hope to see projects outside of Mozilla benefitting from it too.

I would love to see someone package this up for various Linux distributions. You can grab there release here.

Note, this release also features as a preview release of Treehydra. Most of the development lately has been focused on improving Treehydra and building analyses on top of it.