This commit adds `hasSharedLibraries` to `lib.systems`.
We need `plat.hasSharedLibraries` in order to know whether or not to
expect `gcc` (and many other tools) to emit shared libraries (like
`libgcc_s.so`). Many of the GNU build scripts are smart enough that
if you configure them with `--enable-shared` on a platform (such as
`arm-none-eabi`) that doesn't support dynamic linking, they will
simply skip the shared libraries instead of aborting the
`configurePhase`. Unfortunately the missing shared libraries in the
final build product cause very hard-to-troubleshoot problems later
on.
The alternative to introducing `hasSharedLibraries` would be to set
`isStatic` in these situations. However doing so causes
`make-derivation.nix` to insert `-static` between the `pname` and
`hostPlatform` suffix, which is undesirable.
If at some point in the future we eliminate the `-static` suffix,
then `hasSharedLibraries` can be made equal to `!isStatic`.
toLosslessStringMaybe is not used by anything other than lib/tests,
so it can be private to that file.
I don't think this function was terribly well thought-through. If
people start using it, we will become permanently dependent on the
ability to test platforms for equality. It also makes the
elaboration process more fragile, because it encourages code outside
of nixpkgs to become sensitive to the minute details of how
elaboration happens.
We already have examples for these, but since we didn't actually
recognise the doubles, it wasn't possible to build any packages for
them without setting allowUnsupportedSystem.
I imagine this was supposed to be rustc = args.rustc, like the other
two lines. This meant that we accepted both rust and rustc
attributes, with the same effect. I doubt anybody was using the
undocumented, probably-accidental "rust" spelling, but we should
remove it before somebody starts.
In fact, we don't need to set rustc here at all, because no value
platforms.select could return will ever include a rustc key (unlike
the other two), so then rustc will be filled in later, when args is
merged into final.
It makes sense to allow platform definitions to opt out of having libc
at all. One use case would be targetting some obscure new Linux
target that doesn't have a libc implementation yet, and another is
UEFI, which is basically libc-less Windows.
Not having libc is not commonly specified in (GNU) triples (even
Linux's build system will just target either -gnu or -musl depending
on the platform), so instead, we use a separate attribute for it.
- Christmas is over!
- Upstream has changed the name of the target triplet used for the JS
backend from js-unknown-ghcjs to javascript-unknown-ghcjs, since Cabal
calls the architecture "javascript":
6636b67023
Since the triplet is made up anyways, i.e. autoconf does not support
it and Rust uses different triplets for its emscripten backends, we'll
just change it as well.
- Upstream fixed the problem with ar(1) being invoked incorrectly by stage0:
e987e345c8
There is no "aarch64" CPU family — it counts as "arm", as can be seen
from the definition of isAarch64 above.
Checked that stdenv.hostPlatform.isEfi is still true on aarch64-linux.
In the past, most (if not all) armv8 CPUs could also execute armv7. However,
with the advent of Apple Silicon, aarch64 CPUs without any aarch32 capabilities
are now wide-spread among users.
Cross-compilation of anything downstream of gtk3 requires qemu (due to
gobject-introspection) with --target-list=*-linux-user. Without this commit,
those qemu builds will fail on a powerpc64le host due to qemu being configured
with --cpu=powerpc64le instead of --cpu=ppc64le. Unfortunately the build
failure message from qemu in this situation is extremely cryptic.
The root cause turns out not to be the qemu expression, but rather the fact that
on powerpc64le hostPlatform.uname.processor returns the gnu-name (powerpc64le)
for the cpu instead of the linux-name (ppc64le) for the cpu.
uname.processor on mips64el also needs adjustment -- the Linux-name is "mips64"
for both big and little endian (unlike powerpc64, where the Linux-name includes
a "le" suffix):
```
nix@oak:/tmp$ uname -m; lscpu | head -n2
mips64
Architecture: mips64
Byte Order: Little Endian
```
uname.processor on powerpc32 has also been adjusted.
