As far as I can tell, this has never actually done anything, as
LDEMULATION is not exported. I tried exporting it and builds broke,
and as it doesn't seem to have caused any problems as a noop all these
years it didn't seem worth investigating further.
`--enable-deterministic-archives` is a GNU specific strip flag and
causes other strip implementations (for example LLVM's, see #138013)
to fail. Since strip failures are ignored, this means that stripping
doesn't work at all in certain situation (causing unnecessary
dependencies etc.).
To fix this, no longer pass `--enable-deterministic-archives`
unconditionally, but instead add it in a GNU binutils specific strip
wrapper only.
`commonStripFlags` was only used for this flag, so we can remove
it altogether.
Future work could be to make a generic strip wrapper, with support for
nix-support/strip-flags-{before,after} and NIX_STRIP_FLAGS_{BEFORE,AFTER}.
This possibly overkill and unnecessary though -- also with the
additional challenge of incorporating the darwin strip wrapper somehow.
Instead of always supplying flags, apply the flags as defaults. Use
clang's native flags instead of lifting the linker flags from binutils
with `-Wl,`.
If a project is using clang to drive linking, make clang do the right
thing with MACOSX_DEPLOYMENT_TARGET. This can be overridden by command
line arguments. This will cause modern clang to pass
`-platform_version 10.12 0.0.0`, since it doesn't know about the SDK
settings. Older versions of clang will pass down `-macos_version_min`
flags with no sdk version.
At the linker layer, apply a default value for anything left
ambiguous. If nothing is specified, pass a full
`-platform_version`. If only `-macos_version_min` is specified, then
lock down the sdk_version explicitly with `-sdk_version`. If a min
version and sdk version is passed, do nothing.
The `platform` field is pointless nesting: it's just stuff that happens
to be defined together, and that should be an implementation detail.
This instead makes `linux-kernel` and `gcc` top level fields in platform
configs. They join `rustc` there [all are optional], which was put there
and not in `platform` in anticipation of a change like this.
`linux-kernel.arch` in particular also becomes `linuxArch`, to match the
other `*Arch`es.
The next step after is this to combine the *specific* machines from
`lib.systems.platforms` with `lib.systems.examples`, keeping just the
"multiplatform" ones for defaulting.
Currently we set dynamic-linker unconditionally. This breaks
however some static binaries i.e. rust binaries linked against musl.
There is no reason we should set an elf interpreter for static binaries
hence this is skipped if `-static` or `-static-pie` is either passed to
our cc or ld wrapper.
The dynamic loader on powerpc64 is called ld64.so.2 rather than
ld-linux.so.*, and was not matched by the existing pattern.
We reuse the dynamicLinker name from binutils to match a wider set
of platforms and to avoid specifying this information in two places.
Revert the hack and the original faulty commit.
This reverts commit 48264ee506105a2f5e61e5d327599e9f301bd77f.
Revert "Purity checking should accept $TMP and not just /tmp"
This reverts commit fb777be7d2.
I hate the thing too even though I made it, and rather just get rid of
it. But we can't do that yet. In the meantime, this brings us more
inline with autoconf and will make it slightly easier for me to write a
pkg-config wrapper, which we need.
Before, we'd always use `cc = null`, and check for that. The problem is
this breaks for cross compilation to platforms that don't support a C
compiler.
It's a very subtle issue. One might think there is no problem because we
have `stdenvNoCC`, and presumably one would only build derivations that
use that. The problem is that one still wants to use tools at build-time
that are themselves built with a C compiler, and those are gotten via
"splicing". The runtime version of those deps will explode, but the
build time / `buildPackages` versions of those deps will be fine, and
splicing attempts to work this by using `builtins.tryEval` to filter out
any broken "higher priority" packages (runtime is the default and
highest priority) so that both `foo` and `foo.nativeDrv` works.
However, `tryEval` only catches certain evaluation failures (e.g.
exceptions), and not arbitrary failures (such as `cc.attr` when `cc` is
null). This means `tryEval` fails to let us use our build time deps, and
everything comes apart.
The right solution is, as usually, to get rid of splicing. Or, baring
that, to make it so `foo` never works and one has to explicitly do
`foo.*`. But that is a much larger change, and certaily one unsuitable
to be backported to stable.
Given that, we instead make an exception-throwing `cc` attribute, and
create a `hasCC` attribute for those derivations which wish to
condtionally use a C compiler: instead of doing `stdenv.cc or null ==
null` or something similar, one does `stdenv.hasCC`. This allows quering
without "tripping" the exception, while also allowing `tryEval` to work.
No platform without a C compiler is yet wired up by default. That will
be done in a following commit.
