Fails to build with current nightly.

[samgiles]

Several occurrences of:

1082:20 error: use of unstable library feature 'core_intrinsics': intrinsics are unlikely to ever be stabilized, instead they should be used through stabilized interfaces in the rest of the standard library (see issue #0)
/formdata-10625c5507708aaf/out/lib.rs:1082 #[derive_PartialEq]

When adding the feature you get an error in textnonce:

   Compiling textnonce v0.3.4
/Users/sam/.cargo/registry/src/github.com-1ecc6299db9ec823/textnonce-0.3.4/build.rs:20:35: 20:48 error: mismatched types [E0308]
/Users/sam/.cargo/registry/src/github.com-1ecc6299db9ec823/textnonce-0.3.4/build.rs:20         ::serde_codegen::register(&mut registry);
                                                                                                                         ^~~~~~~~~~~~~
/Users/sam/.cargo/registry/src/github.com-1ecc6299db9ec823/textnonce-0.3.4/build.rs:20:35: 20:48 help: run `rustc --explain E0308` to see a detailed explanation
/Users/sam/.cargo/registry/src/github.com-1ecc6299db9ec823/textnonce-0.3.4/build.rs:20:35: 20:48 note: expected type `&mut syntex::Registry`
/Users/sam/.cargo/registry/src/github.com-1ecc6299db9ec823/textnonce-0.3.4/build.rs:20:35: 20:48 note:    found type `&mut syntex::Registry`
/Users/sam/.cargo/registry/src/github.com-1ecc6299db9ec823/textnonce-0.3.4/build.rs:20:35: 20:48 note: Perhaps two different versions of crate `syntex` are being used?
/Users/sam/.cargo/registry/src/github.com-1ecc6299db9ec823/textnonce-0.3.4/build.rs:20         ::serde_codegen::register(&mut registry);
                                                                                                                         ^~~~~~~~~~~~~

Using:
rustc 1.11.0-nightly (5522e678b 2016-06-20)
cargo 0.12.0-nightly (4ba8264 2016-06-19)

[mikedilger]

There is not much more that I can do to fix this kind of version skew until Cargo allows me to specify that "the version of syntex must match whatever serde_codegen (or quasi/aster) is using".

You can pin the version in your cargo.lock file to the one quasi and aster are using (as of today) with:

cargo update -p syntex:0.36.0 --precise 0.35.0

I used to manually set the exact version of syntex, and every week or two I got a bug report and had to bump it. Now I just put "^0" and let downstream (that means you) manage your cargo.lock file. Formdata now works with any version of syntex, and you are responsible for pinning it to the version that aster and quasi are currently using.

[samgiles]

Makes sense - thanks.