This iteration was long, about five weeks (2fcb11a2), I think.
Darwin: it's missing a few thousand binaries and there's a make-netbsd
regression, but I suppose these aren't merge blockers.
buildRustCrate has a handy `include` helper, that only imports those whitelisted
files and folders to the store.
However, the function's matching logic is broken and includes all files,
regardless of whether or not they're whitelisted, as long as the whitelist
contains at least one name (regardless of whether that name exists). This is
because it doesn't take into account that
`lib.strings.removePrefix "foo" "bar" == "bar"` (that is, paths that don't match
the prefix are passed straight through).
This rare sitation was caught when building zoom-us package:
```
automatically fixing dependencies for ELF files
/nix/store/71d65fplq44y9yn2fvkpn2d3hrszracd-auto-patchelf-hook/nix-support/setup-hook: line 213: echo: write error: Broken pipe
/nix/store/71d65fplq44y9yn2fvkpn2d3hrszracd-auto-patchelf-hook/nix-support/setup-hook: line 210: echo: write error: Broken pipe
```
The worst is that derivation continued and resulted into broken package:
https://github.com/NixOS/nixpkgs/pull/55566#issuecomment-470065690
I hope, replacing `grep -q` with `grep` will remove this race condition.
On very large graphs (14k+ paths), we'd end up with a massive in
memory tree of mostly duplication.
We can safely cache trees and point back to them later, saving
memory.
While it is not obvious from the source, cargo sets CARGO_MANIFEST_DIR to an absolute directory. This let to a build problem with the popular "tera" crate using the "pest" crate.
## Cargo details
The variable is set here:
f7c91ba622/src/cargo/core/compiler/compilation.rs (L229)
and computed from the `manifest_path`:
f7c91ba622/src/cargo/core/package.rs (L163)
The manifest path is also exported via `cargo metadata` where you can see that it is absolute.
Whenever we create scripts that are installed to $out, we must use runtimeShell
in order to get the shell that can be executed on the machine we create the
package for. This is relevant for cross-compiling. The only use case for
stdenv.shell are scripts that are executed as part of the build system.
Usages in checkPhase are borderline however to decrease the likelyhood
of people copying the wrong examples, I decided to use runtimeShell as well.
