link-test: add test case for MachO bug 16308

test/link.zig

@@ -92,6 +92,10 @@ pub const cases = [_]Case{
         .build_root = "test/link/macho/bugs/13457",
         .import = @import("link/macho/bugs/13457/build.zig"),
     },
+    .{
+        .build_root = "test/link/macho/bugs/16308",
+        .import = @import("link/macho/bugs/16308/build.zig"),
+    },
     .{
         .build_root = "test/link/macho/dead_strip",
         .import = @import("link/macho/dead_strip/build.zig"),

test/link/macho/bugs/16308/build.zig

@@ -0,0 +1,23 @@
+const std = @import("std");
+
+pub const requires_symlinks = true;
+
+pub fn build(b: *std.Build) void {
+    const test_step = b.step("test", "Test it");
+    b.default_step = test_step;
+
+    const target: std.zig.CrossTarget = .{ .os_tag = .macos };
+
+    const lib = b.addSharedLibrary(.{
+        .name = "a",
+        .root_source_file = .{ .path = "main.zig" },
+        .optimize = .Debug,
+        .target = target,
+    });
+
+    const check = lib.checkObject();
+    check.checkInSymtab();
+    check.checkNotPresent("external");
+
+    test_step.dependOn(&check.step);
+}

test/link/macho/bugs/16308/main.zig

@@ -0,0 +1 @@
+fn abc() void {}