android.resolveTargets ignores API level

[ypsvlq]

Zig's target encodes the API level (e.g. -Dtarget=aarch64-linux-android.26), which affects compilation as emutls is used for API levels below 29.

android.resolveTargets seems to always return API level 29, regardless of what is specified in the Zig target (or to sdk.createApk), which breaks threadlocal variables for lower API levels.

[ypsvlq]

I think standardTargets/resolveTargets should be methods on Apk so they can infer the API level from there, allowing zig build -Dandroid=true -Dandroid_api_level=26 to work properly.

[ypsvlq]

Hardcoding android_api_level = 28 in AndroidTargetQuery.queryTarget would also work as a temporary fix.

[silbinarywolf]

Hey @ypsvlq,

This all seems like a good idea to me. Just putting down how I imagine it looking here. I'm going to be pretty busy over the next month + 1 week at the bare minimum, so if you want to pick this up and do it, that'd be great.

If anything I've written below is dubious or doesn't work in practice, lets perhaps just go for an initial PR where we default to android_api_level = 28 in queryTarget.

Update ResolveTargetOptions to require Android Api Level

src/androidbuild/androidbuild.zig

• Update ResolveTargetOptions, for backwards compatibility, if android_api_level is not set, then default to 28 (.android9)

pub const ResolveTargetOptions = struct {
    /// The target retrieved from b.standardTargetOptions
    default_target: ResolvedTarget,
    /// If true, then retrieve all Android targets rather than using the default target
    all_targets: bool,
    /// (all_targets only) The android API version to target, if set to ".none" then use "default_android_api_level"
    android_api_level: ApiLevel,

    /// Shorthand to query all Android targets
    pub const all: ResolveTargetOptions = .{
        .default_target = undefined,
        .all_targets = true,
        .android_api_level = .none,
    };

    /// If -Dandroid_api_level is not provided, we default to Android 9 for now.
    /// See: https://github.com/silbinarywolf/zig-android-sdk/issues/102
    const default_android_api_level: ApiLevel = .android9;
};

• Update standardTargets and resolveTargets to support -Dandroid_api_level

Update ApiLevel to allow inference from given targets via fromTargets function

I'm not sure how much sense this makes to do, I know this field is how you decide on the android.jar from ~/Android/Sdk/platforms/android-29

const android_targets: []std.Build.ResolvedTarget = android.standardTargets(b, root_target);
const apk = android_sdk.createApk(.{
    .name = exe_name,
    .api_level = .fromTargets(android_targets), // <- Update this to
    .build_tools_version = "36.1.0",
    .ndk_version = "29.0.14206865",
});