`rustpkg`'s `-c` does not work.

[dpc]

Current incoming branch (a6945f2).

I'm trying to install rust-sdl crate:

[mutex:~] (master)% rustpkg  -c "image" install git://github.com/brson/rust-sdl.git
note: fetching from git://github.com/brson/rust-sdl.git using git
note: compiling /home/dpc/.rustpkg/tmp/177b16f99c6316/src/sdl.rc
note: installed sdl v0.3.0
[mutex:~] (master)% strings .rustpkg/lib/libsdl-34b7eedb9132850-0.3.0.so| grep img
[mutex:~] (master)% 

If I build manually the img module is there and everything works. Seems to me that rustpkg does not really pass the -c like it should.

[catamorphism]

rustpkg doesn't have a way to pass along arguments to rustc yet. Not a release blocker, de-milestoning

[pnkfelix]

Adding to the most apparent rustpkg metabug: #5677

[catamorphism]

Closing in favor of the more general #8522 (which will be ready this week).