Tier 1 Support for riscv64-linux

[andrewrk]

Once all these items are complete, we can say that Zig has Tier 1 support for 64-bit RISC-V Linux.

• [x] make sure we can build-exe with -target riscv64-linux-gnu
• [x] make sure we can build-exe with -target riscv64-linux-musl
• [x] ability to build libc for riscv64-linux-gnu (#3340)
• [x] ability to build libc for riscv64-linux-musl
• [ ] make sure stack traces / debug info works & add test coverage
• [x] add the target to the test matrix
• [x] get the full test suite passing
• [ ] figure out a risc-v linux continuous integration testing service and hook it up to zig's CI testing.
• [x] hook up to update download page with risc-v tarballs

[Ivan-Velickovic]

zig build-exe hello.c -lc -target riscv64-linux-musl with version 0.10.0-dev.3660+4a98385b0 works.

[RossComputerGuy]

Looks like traces work, only needs to be added to the test coverage according to the task.

const std = @import("std");

pub fn a() !void {
    try b();
}

pub fn b() !void {
    try c();
}

pub fn c() !void {
    return error.@"I'm a cat";
}

pub fn main() !void {
    try a();
}

error: I'm a cat
/home/ross/ExpidusOS/zig/main.zig:12:5: 0x100b5b7 in c (main)
    return error.@"I'm a cat";
    ^
/home/ross/ExpidusOS/zig/main.zig:8:5: 0x100b6d9 in b (main)
    try c();
    ^
/home/ross/ExpidusOS/zig/main.zig:4:5: 0x100b71b in a (main)
    try b();
    ^
/home/ross/ExpidusOS/zig/main.zig:16:5: 0x100b75d in main (main)
    try a();
    ^

[alexrp]

ability to build libc for riscv64-linux-musl

This can be crossed off now:

❯ cat main.zig
const std = @import("std");
pub fn main() !void {
    std.debug.print("Hello, World!\n", .{});
}
❯ ../zig/build/debug/bin/zig build-exe main.zig -target riscv64-linux
❯ ../zig/build/debug/bin/zig build-exe main.zig -target riscv64-linux-musl -lc

figure out a risc-v linux continuous integration testing service and hook it up to zig's CI testing.

Scaleway's pricing looks quite reasonable: https://labs.scaleway.com/en/em-rv1

Issues to solve:

These are all done.

[alexrp]

ability to build libc for riscv64-linux-gnu

This can also be crossed off as of #20909.

[alexrp]

• add the target to the test matrix

This can be crossed off as of the LLVM 19 upgrade.

[Glavo]

figure out a risc-v linux continuous integration testing service and hook it up to zig's CI testing.

@andrewrk @alexrp Do you need someone to donate some RISC-V physical machines to you?

We are very interested in this and would like to provide some help. Can you provide more detailed requirements?

[alexrp]

@Glavo hey, sorry for the super late response. Probably the most important requirement is that we need physical control over the machines that we run CI on.