return_undefined: { options = { sequences : false, if_return : true, evaluate : true, dead_code : true, conditionals : true, comparisons : true, booleans : true, unused : true, side_effects : true, properties : true, drop_debugger : true, loops : true, hoist_funs : true, keep_fargs : true, keep_fnames : false, hoist_vars : true, join_vars : true, cascade : true, negate_iife : true }; input: { function f0() { } function f1() { return undefined; } function f2() { return void 0; } function f3() { return void 123; } function f4() { return; } function f5(a, b) { console.log(a, b); baz(a); return; } function f6(a, b) { console.log(a, b); if (a) { foo(b); baz(a); return a + b; } return undefined; } function f7(a, b) { console.log(a, b); if (a) { foo(b); baz(a); return void 0; } return a + b; } function f8(a, b) { foo(a); bar(b); return void 0; } function f9(a, b) { foo(a); bar(b); return undefined; } function f10() { return false; } function f11() { return null; } function f12() { return 0; } } expect: { function f0() {} function f1() {} function f2() {} function f3() {} function f4() {} function f5(a, b) { console.log(a, b); baz(a); } function f6(a, b) { console.log(a, b); if (a) { foo(b); baz(a); return a + b; } } function f7(a, b) { console.log(a, b); if (!a) return a + b; foo(b); baz(a); } function f8(a, b) { foo(a); bar(b); } function f9(a, b) { foo(a); bar(b); } function f10() { return !1; } function f11() { return null; } function f12() { return 0; } } } -id.patch: New file. * gnu/local.mk (dist_patch_DATA): Register it. * .patman (keep_change_id): Use it. Series-changes: 3 - New commit Change-Id: I33c03013f6a260b5f5d80212b7b6ebe8a3f97efa