More error checking for unresolved TLDs

Closes #4274

test/compile_errors.zig

@@ -2,6 +2,12 @@ const tests = @import("tests.zig");
 const builtin = @import("builtin");
 
 pub fn addCases(cases: *tests.CompileErrorContext) void {
+    cases.addTest("dependency loop in top-level decl with @TypeInfo",
+        \\export const foo = @typeInfo(@This());
+    , &[_][]const u8{
+        "tmp.zig:1:20: error: dependency loop detected",
+    });
+
     cases.addTest("non-exhaustive enums",
         \\const A = enum {
         \\    a,