For reasons explained in the commit contents, in order to build the
native gnat package for x86_64-darwin, the native gnatboot package for
x86_64-darwin must have access to both the Clang integrated assembler
and the cctools GNU assembler for that platform. This commit creates a
package with both of those assemblers that x86_64-darwin gnatboot can
then be wrapped with.
Co-authored-by: Sandro <sandro.jaeckel@gmail.com>
- Use the 11.0 SDK instead of the 10.12 one on x86_64-darwin;
- Use `NIX_CFLAGS_COMPILE` and `NIX_LDFLAGS` to pass flags to the
compiler instead of patching the Xcode project files; and
- Use xcbuild to build the project.
- Introduce `preLibcCrossHeaders` to bootstrap libgcc and compiler-rt
the same way.
- Organize LLVM bintools as `bintools{-unwrapped,,NoLibc}` for
consistency with GNU Binutils and Apple's cctools.
- Do Android changes for all `llvmPackages` for consistency.
- Improve the way the default GCC and LLVM versions are selected.
I am taking the non-invasive parts of #110914 to hopefully help out with #111988.
In particular:
- Use `lib.makeScopeWithSplicing` to make the `darwin` package set have
a proper `callPackage`.
- Adjust Darwin `stdenv`'s overlays keeping things from the previous
stage to not stick around too much.
- Expose `binutilsNoLibc` / `darwin.binutilsNoLibc` to hopefully get us
closer to a unified LLVM and GCC bootstrap.
Without this change `as` on `aarch64-darwin` is defunct:
```
$ /nix/store/g11xba8ch20zndaf32hfnap46z47b5k3-cctools-port-949.0.1/bin/as -v
/nix/store/g11xba8ch20zndaf32hfnap46z47b5k3-cctools-port-949.0.1/bin/as: assembler (/nix/store/g11xba8ch20zndaf32hfnap46z47b5k3-cctools-port-949.0.1/libexec/as/arm64/as or /nix/store/g11xba8ch20zndaf32hfnap46z47b5k3-cctools-port-949.0.1/libexec/as/arm64/as) for architecture arm64 not installed
Installed assemblers are:
/nix/store/g11xba8ch20zndaf32hfnap46z47b5k3-cctools-port-949.0.1/libexec/as/ppc64/as for architecture ppc64
/nix/store/g11xba8ch20zndaf32hfnap46z47b5k3-cctools-port-949.0.1/libexec/as/x86_64/as for architecture x86_64
/nix/store/g11xba8ch20zndaf32hfnap46z47b5k3-cctools-port-949.0.1/libexec/as/ppc/as for architecture ppc
/nix/store/g11xba8ch20zndaf32hfnap46z47b5k3-cctools-port-949.0.1/libexec/as/i386/as for architecture i386
/nix/store/g11xba8ch20zndaf32hfnap46z47b5k3-cctools-port-949.0.1/libexec/as/arm/as for architecture arm
```
Apple defaults to Clang in all cases from what I see, but nixpkgs prefers `cctools`: #51881.
The only remaining use-case for cf-private are symbols that are not
available in the opensource build. This generally solved the problem
because of it's setup-hook.
CoreFoundation is included by the stdenv, moving the decision of what
version should be used there makes it possible to override it entirely
rather then prepending flags like cf-private does which can be
unreliable.
