Zig + IDF support

[kassane]

Information

• Language: Ziglang
• Toolchain: Zig
• Use IDF: Yes (use heap allocator)
• Bare-Metal: No
• FFI: C to Zig

Details

The example uses Zig v0.12.0-dev that has been forked to support the xtensa architecture in addition to other architectures available from the llvm codegen. And also show a idf-wrapper written in ziglang where modules are obtained from the zig-pkg ([decentralized] package manager) zon file.

Note: Hopefully it's pretty clear that the main application is placeholder.c that is attached to main/cmakelists.txt and zig is just a dependency in static library format.
CMake does all the work, but it shares some information with build.zig, including compiled objects that are added to the zig library, avoiding undefined reference (depending on the execution order when building).

cc: @georgik

Reference

• Other programming languages  #10

[georgik]

Thank you very much @kassane . This is impressive work. I'm very glad that we can add Zig into results.
I've tried some bare metal Zig before on ESP32, yet solution with ESP-IDF makes much more sense in this stage.

[kassane]

Thanks!
Based on CI error: https://github.com/georgik/esp32-lang-lab/actions/runs/8466882009/job/23196614994#step:4:1478

v5.1.3-416-gd23b7a0361 unparsed version.

esp32-lang-lab/examples/zig/esp-idf-v5/get-started/hello_world/main/hello.zig

Lines 20 to 24 in c7562a5

	idf.ESP_LOG(allocator, tag,
	\\[ESP-IDF Info]
	\\* Version: {s}
	\\
	, .{idf.Version.get().toString(allocator)});

Implementation: https://github.com/kassane/zig-esp-idf-sample/blob/a4eaae1683ffb303142dce2ad50d4ec63eba69cf/imports/version.zig#L16-L39

Need to improve panic_handler with esp_backtrace (TODO). I tried zig @breakpoint, however the system reboots all the time.
In general, ziglang's panic_handler works better if the application is only built by the zig compiler, in this case the host is gcc(crosstool-ng).

[kassane]

Version fixed: kassane/zig-esp-idf-sample@e571483.

When you want you can update zon file.

cd /path/{build.zig.zon path}
# overwrite idf commit-tag/branch and hash
$> zig fetch --save=idf git+https://github.com/kassane/zig-esp-idf-sample#e57148332bb634c342412756db428b9a5b658387