This reduces the number of Python builds in the bootstrap to two: a minimal build and a normal build. Both have LTO disabled, which is required due to missing LLVM LTO libraries. This is necessary to correctly enable LTO builds in Python because it needs `llvm-ar` from `stdenv.cc.cc.libllvm`, which does not exist in the bootstrap.
Fetchers can use the `curl` binary from the bootstrap tools. Allowing packages in the Darwin bootstrap to link curl makes any curl update cause a full rebuild on Darwin, which is undesirable.
After https://github.com/NixOS/nixpkgs/pull/322388, darwin.cctools is just Apple’s cctools again. The replacement for what the bootstrap tools wants is darwin.binutils-unwrapped.
GNU binutils is not preferred on Darwin, and newer versions have issues building. Make it an evaluation error to use it in the Darwin stdenv bootstrap.
- Only link binaries that exist for stage 0 cctools and LLVM bintools;
- Drop cctools-llvm in favor of the updated darwin.binutils; and
- Update llvm-manages Python overrides (needed for newer versions of LLVM).
Most Linux distributions are enabling this these days and it does
protect against real world vulnerabilities as demonstrated by
CVE-2018-16864 and CVE-2018-16865.
Fix#53753.
Information on llvm version support gleaned from
6609892a2d68e07da3e5092507a730
Information on gcc version support a lot harder to gather,
but both 32bit and 64bit arm do appear to be supported
based on the test suite.
libiconv-darwin depends on Meson, which (indirectly) depends on
libiconv. When libiconv-darwin is set as libiconv, it will cause an
infinite recursion. Avoid the infinite recursion by using libiconvReal
in stage 1. Every stage after that can use libiconv-darwin.
The cc and bintools wrapper contained ad hoc bootstrapping logic for
expand-response-params (which was callPackage-ed in a let binding). This
lead to the strange situation that the bootstrapping logic related to
expand-response-params is split between the wrapper derivations (where
it is duplicated) and the actual stdenv bootstrapping.
To clean this up, the wrappers simply should take expand-response-params
as an ordinary input: They need an adjacent expand-response-params (i.e.
one that runs on their host platform), but don't care about the how.
Providing this is only problematic during stdenv bootstrapping where we
have to pull it from the previous stage at times.
We don't need to artificially make sure that we can execute the wrapper
scripts on the build platform by using stdenv's shell (which comes from
buildPackages) since our cross infrastructure will get us the wrapper
from buildPackages. The upside of this change is that cross-compiled
wrappers (e.g. pkgsCross.aarch64-multiplatform.gcc) will actually work
when executed!
For bootstrapping this is also not a problem, since we have a long
build->build platform chain so runtimeShell is just as good as
stdenvNoCC.shell. We do fall back to old ways, though, by explicitly
using the bootstrap-tools shell in stage2, so the adjacent bash is only
used from stage4 onwards. This is unnecessary in principle (I'll try
removing this hack in the future), but ensures this change causes zero
rebuilds.
Setting the SDK root by default allows `overrideSDK` to correctly set
the SDK version when using a different SDK. It also allows the correct
SDK version to be set when using an older deployment target. Not setting
the correct SDK version can result in unexpected behavior at runtime.
Examples:
* Automatic dark mode switching requires linking against an SDK version
of 10.14 or newer. With the current behavior, the only way to do this
is by using a 10.14+ deployment target even when the application
supports older platforms when build with a newer SDK.
* MetalD3D checks that the system version is at least 14.0. The API it
uses returns a compatibility version when the the SDK is older than
11.0, which causes it to display an error and terminate the
application even when even when its requirements are all met.
