Tool to detect/display function dependencies in Rust crates

[pcwalton]

This would be useful for many things:

• Figuring out which functions are dead and can be removed.
• Visualize function dependencies (with dot).
• Be the basis for a Rust ccache workalike.
• On-demand, lazy unit tests.

[pcwalton]

I have call graph generation working in a branch.

[catamorphism]

@pcwalton did you ever integrate this?

[pcwalton]

No, it's assuredly bitrotted by now.

[catamorphism]

I'll take this on as a first step towards #2369

[catamorphism]

Bumping to 0.7.

[catamorphism]

Not critical for 0.7. Nominating for milestone 3, feature-complete.

[graydon]

just a bug, removing milestone/nomination.

[emberian]

Such a tool also needs to be able to tell me everywhere a type is used, for maximum utility. Since we have inference, it's near impossible to grep for a type or function returning that type to see where it's used.

[emberian]

Visiting for triage; nothing to add.

[huonw]

Triage

Figuring out which functions are dead and can be removed.

is done, as the dead_code lint pass, but it doesn't collect any more detailed information than which functions are public or are called by public functions (or called by functions called by public ones, etc, etc).

[steveklabnik]

I'm pulling a massive triage effort to get us ready for 1.0. As part of this, I'm moving stuff that's wishlist-like to the RFCs repo, as that's where major new things should get discussed/prioritized.

This issue has been moved to the RFCs repo: rust-lang/rfcs#605