In Autoconf, some old NetBSD targets like "i686-unknown-netbsd" are
interpreted as a.out, not elf, and virtually nothing supports it. We
need to specify e.g. "i686-unknown-netbsdelf" to get the right
behaviour.
Stating that CPUs and the isCompatible relation forms a category (or
preorder) is correct but overtly technical. We can state it more
clearly for readers unfamiliar with mathematics while retaining some
keywords to be useful to technical readers.
PPC64 supports two ABIs: ELF v1 and v2.
ELFv1 is historically what GCC and most packages expect, but this is
changing because musl outright does not work with ELFv1. So any distro
which uses musl must use ELFv2. Many other platforms are moving to ELFv2
too, such as FreeBSD (as of v13) and Gentoo (as of late 2020).
Since we use musl extensively, let's default to ELFv2.
Nix gives us the power to specify this declaratively for the entire
system, so ELFv1 is not dropped entirely. It can be specified explicitly
in the target config, e.g. "powerpc64-unknown-linux-elfv1". Otherwise the
default is "powerpc64-unknown-linux-elfv2". For musl,
"powerpc64-unknown-linux-musl" must use elfv2 internally to function.
Adds pkgsCross.wasm32 and pkgsCross.wasm64. Use it to build Nixpkgs
with a WebAssembly toolchain.
stdenv/cross: use static overlay on isWasm
isWasm doesn’t make sense dynamically linked.
It is useful to make these dynamic and not bake them into gcc. This
means we don’t have to rebuild gcc to change these values. Instead, we
will pass cflags to gcc based on platform values. This was already
done hackily for android gcc (which is multi-target), but not for our
own gccs which are single target.
To accomplish this, we need to add a few things:
- add ‘arch’ to cpu
- add NIX_CFLAGS_COMPILE_BEFORE flag (goes before args)
- set -march everywhere
- set mcpu, mfpu, mmode, and mtune based on targetPlatform.gcc flags
cc-wrapper: only set -march when it is in the cpu type
Some architectures don’t have a good mapping of -march. For instance
POWER architecture doesn’t support the -march flag at all!
https://gcc.gnu.org/onlinedocs/gcc/RS_002f6000-and-PowerPC-Options.html#RS_002f6000-and-PowerPC-Options
eabihf is an abi that can be used with ARM architectures that support
the “hard float”. It should probably only be used with ARM32 when you
are absolutely sure your binaries will run on ARM systems with a FPU.
Also, add an example "armhf-embedded" to match the preexisting
arm-embedded system. qmk_firmware needs hard float in a few places, so
add them here to get that to work.
Fixes #51184
This has been not touched in 6 years. Let's remove it to cause less
problems when adding new cross-compiling infrastructure.
This also simplify gcc significantly.
binutils expects x86_64-unknown-netbsd<version> (only 3 parts!). Any other combo seems to fail.
Also handle darwin versions similarly.
/cc @Ericson2314
There are two different official variations which differ in their float
support, so such a blanket statement is invalid.
`lib.systems.platforms.*android` already handles each case correctly.
Correcting an error in 827ef09140.
ARM ABIs now have a float field. This is used as a fallback to lessen
our use of `platform.gcc.float`. I didn't know what the MIPs convention
is so I kept using `platform.gcc.float` in that case.
