zig/test/behavior/export_builtin.zig

const builtin = @import("builtin");
const std = @import("std");
const expect = std.testing.expect;

test "exporting enum value" {
    if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest;
    if (builtin.cpu.arch.isSpirv()) return error.SkipZigTest;

    const S = struct {
        const E = enum(c_int) { one, two };
        const e: E = .two;
        comptime {
            @export(&e, .{ .name = "e" });
        }
    };
    try expect(S.e == .two);
}

test "exporting using namespace access" {
    if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest;
    if (builtin.cpu.arch.isSpirv()) return error.SkipZigTest;

    const S = struct {
        const Inner = struct {
            const x: u32 = 5;
        };
        comptime {
            @export(&Inner.x, .{ .name = "foo", .linkage = .strong });
        }
    };

    _ = S.Inner.x;
}

test "exporting comptime-known value" {
    if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest;
    if (builtin.zig_backend == .stage2_c) return error.SkipZigTest;
    if (builtin.cpu.arch.isSpirv()) return error.SkipZigTest;

    const x: u32 = 10;
    @export(&x, .{ .name = "exporting_comptime_known_value_foo" });
    const S = struct {
        extern const exporting_comptime_known_value_foo: u32;
    };
    try expect(S.exporting_comptime_known_value_foo == 10);
}