Commit 4e5b5356094a63a13955c757cb2713f120fa920e | zig

author	Andrew Kelley <andrew@ziglang.org> 2026-08-14 08:39:05+02:00
committer	Andrew Kelley <andrew@ziglang.org> 2026-08-14 08:39:05+02:00
log	4e5b5356094a63a13955c757cb2713f120fa920e
tree	80e4b93f3f7159780bba5bbe9fd13b0544ebc46c
parent	613c03321a0970cce3a5d04ede04ab4a24ac1dbb
parent	bc1f280a77ce118300d3f486932c5768911b0e6f

Merge pull request 'Maker: detect modifications to configurer and recompile it' (#36485) from reconfigure into master

Reviewed-on: https://codeberg.org/ziglang/zig/pulls/36485

6 files changed, 259 insertions(+), 113 deletions(-)

lib
- compiler
  - Maker.zig
  - Maker
    Step.zig
    Watch.zig
    Watch
    FsEvents.zig
- std
  - Build
    Cache.zig
src
- main.zig

lib/compiler/Maker.zig+113-45

...	...	@@ -44,6 +44,10 @@ gpa: Allocator,
44	44	graph: *Graph,
45	45	install_paths: InstallPaths,
46	46	scanned_config: *const ScannedConfig,
	47	/// Includes an extra auto-generated placeholder Step at the end that indicates
	48	/// configure must be rerun. It is done this way so that the hot path of file
	49	/// system watching does not need to make any special cases, and to avoid more
	50	/// OS-specific logic in file system watching implementation.
47	51	steps: []Step,
48	52	generated_files: []Path,
49	53	run_args: ?[]const []const u8,
...	...	@@ -221,7 +225,7 @@ pub fn main(init: process.Init.Minimal) !void {
221	225	var skip_oom_steps = false;
222	226	var test_timeout_ns: ?u64 = null;
223	227	var color: Color = .settingFromEnvironment(&graph.environ_map);
224		var watch = false;
	228	var watch_flag = false;
225	229	var fuzz: ?Fuzz.Mode = null;
226	230	var debounce_interval_ms: u16 = 50;
227	231	var listen: bool = false;
...	...	@@ -470,7 +474,7 @@ pub fn main(init: process.Init.Minimal) !void {
470	474	} else if (mem.eql(u8, arg, "--verbose-llvm-ir")) {
471	475	graph.verbose_llvm_ir = true;
472	476	} else if (mem.eql(u8, arg, "--watch")) {
473		watch = true;
	477	watch_flag = true;
474	478	} else if (mem.eql(u8, arg, "--time-report")) {
475	479	graph.time_report = true;
476	480	if (webui_listen == null) webui_listen = .{ .ip6 = .loopback(0) };
...	...	@@ -570,7 +574,7 @@ pub fn main(init: process.Init.Minimal) !void {
570	574	}
571	575
572	576	const early_exit_mode = fetch_only or help_menu or steps_menu or print_configuration != .none;
573		const server_mode = !early_exit_mode and (watch or webui_listen != null or fuzz != null or listen);
	577	const server_mode = !early_exit_mode and (watch_flag or webui_listen != null or fuzz != null or listen);
574	578
575	579	process.raiseFileDescriptorLimit();
576	580
...	...	@@ -697,7 +701,7 @@ pub fn main(init: process.Init.Minimal) !void {
697	701	var protocol_server_allocation: AvoidableServer = undefined;
698	702	const protocol_server: ?*AvoidableServer = if (listen) s: {
699	703	if (builtin.single_threaded) fatal("--listen is not yet supported on single-threaded hosts", .{});
700		if (watch) fatal("using '--watch' and '--listen' together is not supported", .{});
	704	if (watch_flag) fatal("using '--watch' and '--listen' together is not supported", .{});
701	705	if (fuzz != null) fatal("using '--fuzz' and '--listen' together is not supported", .{});
702	706	if (step_names.items.len > 0) fatal("build steps must be provided over the protocol instead of using CLI arguments", .{});
703	707	protocol_server_allocation = .{
...	...	@@ -708,7 +712,12 @@ pub fn main(init: process.Init.Minimal) !void {
708	712	break :s &protocol_server_allocation;
709	713	} else null;
710	714
711		while (true) {
	715	configure: while (true) {
	716	// Set of files that, if modified, imply that recompiling and rerunning
	717	// configurer is needed.
	718	var configure_source_files: Cache.Manifest.Files = .empty;
	719	defer Cache.Manifest.freeFiles(gpa, &configure_source_files);
	720
712	721	// If this fails, we can still start the server and wait for user
713	722	// to request a rebuild. If it returns error.FailedButCacheIntact
714	723	// we can even still do file system watching and automatically
...	...	@@ -730,6 +739,7 @@ pub fn main(init: process.Init.Minimal) !void {
730	739	.fetch_only = fetch_only,
731	740	.print_configuration = print_configuration,
732	741	.forks = forks.items,
	742	.src_files = &configure_source_files,
733	743	})) \|scanned_config\| {
734	744	if (help_menu) {
735	745	scanned_config.printUsage(&graph, initStdoutWriter(io)) catch \|err\| switch (err) {
...	...	@@ -766,7 +776,9 @@ pub fn main(init: process.Init.Minimal) !void {
766	776	.include = install_include_path,
767	777	},
768	778
769		.steps = try arena.alloc(Step, scanned_config.configuration.steps.len),
	779	// Extra step at the end which is the autogenerated placeholder
	780	// step which indicates that we need to reconfigure.
	781	.steps = try arena.alloc(Step, scanned_config.configuration.steps.len + 1),
770	782	.generated_files = try arena.alloc(Path, scanned_config.configuration.generated_files_len),
771	783	.run_args = run_args,
772	784
...	...	@@ -776,7 +788,7 @@ pub fn main(init: process.Init.Minimal) !void {
776	788	.skip_oom_steps = skip_oom_steps,
777	789	.unit_test_timeout_ns = test_timeout_ns,
778	790
779		.watch = watch,
	791	.watch = watch_flag,
780	792	.web_server = web_server,
781	793	.protocol_server = protocol_server,
782	794	.protocol_server_mutex = .init,
...	...	@@ -789,7 +801,7 @@ pub fn main(init: process.Init.Minimal) !void {
789	801	.multiline_errors = multiline_errors,
790	802	.summary = summary orelse if (listen)
791	803	.none
792		else if (watch or webui_listen != null)
	804	else if (watch_flag or webui_listen != null)
793	805	.new
794	806	else
795	807	.failures,
...	...	@@ -808,7 +820,8 @@ pub fn main(init: process.Init.Minimal) !void {
808	820	if (protocol_server) \|s\| {
809	821	try s.serveStringMessage(.bsp_configuration, try arena.print("{f}", .{scanned_config.path}));
810	822
811		var w: ?Watch = null;
	823	var watch: ?Watch = null;
	824	defer if (watch) \|*w\| w.deinit();
812	825
813	826	const Event = union(enum) {
814	827	message: Reader.Error!Client.Message.Header,
...	...	@@ -843,7 +856,7 @@ pub fn main(init: process.Init.Minimal) !void {
843	856	try select.concurrent(.message, Server.receiveMessage, .{s});
844	857
845	858	maker.watch = body.flags.watch;
846		maker.prepare(steps) catch \|err\| switch (err) {
	859	maker.prepare(steps, &configure_source_files) catch \|err\| switch (err) {
847	860	error.DependencyLoopDetected, error.InsufficientMemory => {
848	861	// TODO handle DependencyLoopDetected as error.FailedButCacheIntact
849	862	// and handle InsufficientMemory as error.AlreadyReported
...	...	@@ -857,10 +870,13 @@ pub fn main(init: process.Init.Minimal) !void {
857	870
858	871	if (body.flags.watch) {
859	872	if (!Watch.have_impl) unreachable;
860		if (w == null) w = try .init(&maker);
	873	if (watch == null) watch = try .init(&maker);
861	874
862		try w.?.update(maker.step_stack.keys());
863		try select.concurrent(.fs_event, Watch.wait, .{ &w.?, if (in_debounce) .{ .ms = debounce_interval_ms } else .none });
	875	try updateWatch(&maker, &watch.?);
	876	try select.concurrent(.fs_event, Watch.wait, .{
	877	&watch.?,
	878	if (in_debounce) .{ .ms = debounce_interval_ms } else .none,
	879	});
864	880	}
865	881
866	882	continue :loop try select.await();
...	...	@@ -870,7 +886,13 @@ pub fn main(init: process.Init.Minimal) !void {
870	886	},
871	887	.fs_event => \|payload\| {
872	888	if (!Watch.have_impl) unreachable;
873		switch (try payload) {
	889	switch (payload catch \|err\| switch (err) {
	890	error.MustReconfigure => {
	891	try io.sleep(.fromMilliseconds(debounce_interval_ms), .awake);
	892	continue :configure;
	893	},
	894	else => \|e\| fatal("file watching failed: {t}", .{e}),
	895	}) {
874	896	.timeout => {
875	897	assert(in_debounce);
876	898	markFailedStepsDirty(&maker);
...	...	@@ -880,7 +902,10 @@ pub fn main(init: process.Init.Minimal) !void {
880	902	.dirty => in_debounce = true,
881	903	.clean => {},
882	904	}
883		try select.concurrent(.fs_event, Watch.wait, .{ &w.?, if (in_debounce) .{ .ms = debounce_interval_ms } else .none });
	905	try select.concurrent(.fs_event, Watch.wait, .{
	906	&watch.?,
	907	if (in_debounce) .{ .ms = debounce_interval_ms } else .none,
	908	});
884	909	continue :loop try select.await();
885	910	},
886	911	}
...	...	@@ -889,7 +914,7 @@ pub fn main(init: process.Init.Minimal) !void {
889	914	const initial_steps = try maker.resolveTopLevelSteps(step_names.items);
890	915	defer gpa.free(initial_steps);
891	916
892		maker.prepare(initial_steps) catch \|err\| switch (err) {
	917	maker.prepare(initial_steps, &configure_source_files) catch \|err\| switch (err) {
893	918	error.DependencyLoopDetected, error.InsufficientMemory => {
894	919	// TODO handle DependencyLoopDetected as error.FailedButCacheIntact
895	920	// and handle InsufficientMemory as error.AlreadyReported
...	...	@@ -900,10 +925,11 @@ pub fn main(init: process.Init.Minimal) !void {
900	925	};
901	926
902	927	var w: Watch = w: {
903		if (!watch) break :w undefined;
	928	if (!watch_flag) break :w undefined;
904	929	if (!Watch.have_impl) fatal("--watch not yet implemented for {t}", .{native_os});
905	930	break :w try .init(&maker);
906	931	};
	932	defer w.deinit();
907	933
908	934	if (web_server) \|ws\| try ws.updateConfiguration(&maker);
909	935
...	...	@@ -918,7 +944,7 @@ pub fn main(init: process.Init.Minimal) !void {
918	944
919	945	if (web_server) \|ws\| {
920	946	const c = &scanned_config.configuration;
921		assert(!watch); // fatal error after CLI parsing
	947	assert(!watch_flag); // fatal error after CLI parsing
922	948	while (true) switch (try ws.wait()) {
923	949	.rebuild => {
924	950	for (maker.step_stack.keys()) \|step_index\| {
...	...	@@ -938,7 +964,7 @@ pub fn main(init: process.Init.Minimal) !void {
938	964	// Comptime-known guard to prevent including the logic below when `!Watch.have_impl`.
939	965	if (!Watch.have_impl) unreachable;
940	966
941		try w.update(maker.step_stack.keys());
	967	try updateWatch(&maker, &w);
942	968
943	969	// Wait until a file system notification arrives. Read all such events
944	970	// until the buffer is empty. Then wait for a debounce interval, resetting
...	...	@@ -950,21 +976,34 @@ pub fn main(init: process.Init.Minimal) !void {
950	976	w.dir_count, countSubProcesses(&maker),
951	977	}) catch &caption_buf;
952	978	var debouncing_node = main_progress_node.start(caption, 0);
	979	defer debouncing_node.end();
953	980	var in_debounce = false;
954		while (true) switch (try w.wait(if (in_debounce) .{ .ms = debounce_interval_ms } else .none)) {
955		.timeout => {
956		assert(in_debounce);
957		debouncing_node.end();
958		markFailedStepsDirty(&maker);
959		continue :rebuild;
960		},
961		.dirty => if (!in_debounce) {
962		in_debounce = true;
963		debouncing_node.end();
964		debouncing_node = main_progress_node.start("Debouncing (Change Detected)", 0);
965		},
966		.clean => {},
967		};
	981	while (true) {
	982	const timeout: Watch.Timeout = if (in_debounce) .{ .ms = debounce_interval_ms } else .none;
	983	switch (w.wait(timeout) catch \|err\| switch (err) {
	984	error.MustReconfigure => {
	985	debouncing_node.end();
	986	debouncing_node = main_progress_node.start("Debouncing (Change Detected)", 0);
	987	try io.sleep(.fromMilliseconds(debounce_interval_ms), .awake);
	988	continue :configure;
	989	},
	990	else => \|e\| fatal("file watching failed: {t}", .{e}),
	991	}) {
	992	.timeout => {
	993	assert(in_debounce);
	994	debouncing_node.end();
	995	debouncing_node = .none;
	996	markFailedStepsDirty(&maker);
	997	continue :rebuild;
	998	},
	999	.dirty => if (!in_debounce) {
	1000	in_debounce = true;
	1001	debouncing_node.end();
	1002	debouncing_node = main_progress_node.start("Debouncing (Change Detected)", 0);
	1003	},
	1004	.clean => {},
	1005	}
	1006	}
968	1007	}
969	1008	} else \|err\| {
970	1009	const can_fs_watch = switch (err) {
...	...	@@ -982,7 +1021,7 @@ pub fn main(init: process.Init.Minimal) !void {
982	1021	if (protocol_server != null) {
983	1022	fatal("(zig build system) TODO send error messages to client when build.zig compilation fails", .{});
984	1023	}
985		if (watch and can_fs_watch) {
	1024	if (watch_flag and can_fs_watch) {
986	1025	fatal("(zig build system) TODO set up fs watching even when build.zig compilation fails", .{});
987	1026	} else {
988	1027	fatal("(zig build system) TODO stay running and wait for user to request rebuild even when build.zig compilation fails", .{});
...	...	@@ -991,6 +1030,15 @@ pub fn main(init: process.Init.Minimal) !void {
991	1030	}
992	1031	}
993	1032
	1033	/// Temporarily adds the reconfigure pseudostep to step_stack, calls
	1034	/// `Watch.update`, and then pops it again.
	1035	fn updateWatch(maker: Maker, watch: Watch) !void {
	1036	const step_stack = &maker.step_stack;
	1037	try step_stack.putNoClobber(maker.gpa, @fromBackingInt(@intCast(maker.steps.len - 1)), {});
	1038	defer _ = step_stack.pop().?;
	1039	try watch.update(step_stack.keys());
	1040	}
	1041
994	1042	const ConfigureOptions = struct {
995	1043	configure_argv: [][]const u8,
996	1044	conf_argv_index_build_root: usize,
...	...	@@ -1008,6 +1056,7 @@ const ConfigureOptions = struct {
1008	1056	fetch_only: bool,
1009	1057	print_configuration: PrintConfiguration,
1010	1058	forks: []Fork,
	1059	src_files: *Cache.Manifest.Files,
1011	1060	};
1012	1061
1013	1062	fn configure(graph: *Graph, options: ConfigureOptions) !ScannedConfig {
...	...	@@ -1362,14 +1411,14 @@ fn configure(graph: *Graph, options: ConfigureOptions) !ScannedConfig {
1362	1411
1363	1412	if (config_man) \|man\| {
1364	1413	if (try man.hit(compile_prog_node)) {
	1414	log.debug("configuration cache hit", .{});
1365	1415	const digest = man.final();
1366		break :cp .{
1367		.{
1368		.root_dir = graph.local_cache_root,
1369		.sub_path = try arena.print("c/{s}", .{&digest}),
1370		},
1371		man.toOwnedLock(),
	1416	const path: Path = .{
	1417	.root_dir = graph.local_cache_root,
	1418	.sub_path = try arena.print("c/{s}", .{&digest}),
1372	1419	};
	1420	options.src_files.* = man.takeFiles();
	1421	break :cp .{ path, man.toOwnedLock() };
1373	1422	}
1374	1423	}
1375	1424	const configure_exe_path: Path = if (std.zig.buildExeSubprocess(gpa, io, .{
...	...	@@ -1505,6 +1554,7 @@ fn configure(graph: *Graph, options: ConfigureOptions) !ScannedConfig {
1505	1554	});
1506	1555	};
1507	1556	man.writeManifest() catch \|err\| log.warn("failed to write cache manifest: {t}", .{err});
	1557	options.src_files.* = man.takeFiles();
1508	1558	break :cp .{ final_path, man.toOwnedLock() };
1509	1559	}
1510	1560	};
...	...	@@ -2119,7 +2169,13 @@ fn markFailedStepsDirty(maker: *Maker) void {
2119	2169	for (all_steps) \|step_index\| {
2120	2170	const step = maker.stepByIndex(step_index);
2121	2171	switch (step.state) {
2122		.dependency_failure, .dependency_skipped, .failure, .skipped => _ = maker.invalidateResult(step),
	2172	.dependency_failure,
	2173	.dependency_skipped,
	2174	.failure,
	2175	.skipped,
	2176	=> _ = maker.invalidateResult(step) catch \|err\| switch (err) {
	2177	error.MustReconfigure => unreachable,
	2178	},
2123	2179	else => continue,
2124	2180	}
2125	2181	}
...	...	@@ -2173,7 +2229,11 @@ fn resolveTopLevelSteps(maker: *Maker, step_names: []const []const u8) ![]const
2173	2229	return try gpa.dupe(Configuration.Step.Index, result.keys());
2174	2230	}
2175	2231
2176		fn prepare(maker: *Maker, step_indices: []const Configuration.Step.Index) !void {
	2232	fn prepare(
	2233	maker: *Maker,
	2234	step_indices: []const Configuration.Step.Index,
	2235	configure_source_files: *const Cache.Manifest.Files,
	2236	) !void {
2177	2237	const gpa = maker.gpa;
2178	2238	const graph = maker.graph;
2179	2239	const arena = graph.arena;
...	...	@@ -2182,10 +2242,17 @@ fn prepare(maker: *Maker, step_indices: []const Configuration.Step.Index) !void
2182	2242	const step_stack = &maker.step_stack;
2183	2243	const c = &maker.scanned_config.configuration;
2184	2244
2185		for (maker.steps, 0..) \|*step, step_index_usize\| {
	2245	// The last element is a reserved special pseudostep which contains the
	2246	// watch inputs for the configurer executable.
	2247	for (maker.steps[0 .. maker.steps.len - 1], 0..) \|*step, step_index_usize\| {
2186	2248	const step_index: Configuration.Step.Index = @fromBackingInt(@intCast(step_index_usize));
2187	2249	step.* = .{ .extended = .init(step_index.ptr(c).flags(c).tag) };
2188	2250	}
	2251	{
	2252	const last_step = &maker.steps[maker.steps.len - 1];
	2253	last_step.* = .{ .extended = .init(.top_level) };
	2254	try last_step.setWatchInputsFromManifestFiles(maker, configure_source_files, graph.cache.prefixes());
	2255	}
2189	2256
2190	2257	try initial_steps.ensureUnusedCapacity(gpa, step_indices.len);
2191	2258	try step_stack.ensureUnusedCapacity(gpa, step_indices.len);
...	...	@@ -3045,14 +3112,15 @@ fn constructGraphAndCheckForDependencyLoop(
3045	3112	/// When file watching, prepares the step for being re-evaluated. Returns
3046	3113	/// `true` if the step was newly invalidated, `false` if it was already
3047	3114	/// invalidated.
3048		pub fn invalidateResult(maker: Maker, step: Step) bool {
	3115	pub fn invalidateResult(maker: Maker, step: Step) error{MustReconfigure}!bool {
	3116	if (step == &maker.steps[maker.steps.len - 1]) return error.MustReconfigure;
3049	3117	if (step.state == .precheck_done) return false;
3050	3118	assert(step.pending_deps == 0);
3051	3119	step.state = .precheck_done;
3052	3120	step.reset(maker);
3053	3121	for (step.dependants.items) \|dependant_index\| {
3054	3122	const dependant = maker.stepByIndex(dependant_index);
3055		_ = invalidateResult(maker, dependant);
	3123	_ = try invalidateResult(maker, dependant);
3056	3124	dependant.pending_deps += 1;
3057	3125	}
3058	3126	return true;

lib/compiler/Maker/Step.zig+11-3

...	...	@@ -781,12 +781,20 @@ pub fn writeManifestAndWatch(s: Step, maker: Maker, man: *Cache.Manifest) !voi
781	781	try setWatchInputsFromManifest(s, maker, man);
782	782	}
783	783
784		fn setWatchInputsFromManifest(s: Step, maker: Maker, man: *Cache.Manifest) !void {
	784	pub fn setWatchInputsFromManifest(s: Step, maker: Maker, man: *Cache.Manifest) !void {
	785	return setWatchInputsFromManifestFiles(s, maker, &man.files, man.cache.prefixes());
	786	}
	787
	788	pub fn setWatchInputsFromManifestFiles(
	789	s: *Step,
	790	maker: *Maker,
	791	files: *const Cache.Manifest.Files,
	792	prefixes: []const Cache.Directory,
	793	) !void {
785	794	const graph = maker.graph;
786	795	const arena = graph.arena; // TODO don't leak into process arena
787		const prefixes = man.cache.prefixes();
788	796	clearWatchInputs(s, maker);
789		for (man.files.keys()) \|file\| {
	797	for (files.keys()) \|file\| {
790	798	// The file path data is freed when the cache manifest is cleaned up at the end of `make`.
791	799	const sub_path = try arena.dupe(u8, file.prefixed_path.sub_path);
792	800	try addWatchInputFromPath(s, maker, .{

lib/compiler/Maker/Watch.zig+84-46

...	...	@@ -49,7 +49,10 @@ const Os = switch (builtin.os.tag) {
49	49	poll_fds: std.array_hash_map.Auto(MountId, posix.pollfd),
50	50
51	51	const MountId = i32;
52		const HandleTable = std.array_hash_map.Custom(FileHandle, struct { mount_id: MountId, reaction_set: ReactionSet }, FileHandle.Adapter, false);
	52	const HandleTable = std.array_hash_map.Custom(FileHandle, struct {
	53	mount_id: MountId,
	54	reaction_set: ReactionSet,
	55	}, FileHandle.Adapter, false);
53	56
54	57	const fan_mask: std.os.linux.fanotify.MarkMask = .{
55	58	.CLOSE_WRITE = true,
...	...	@@ -81,7 +84,7 @@ const Os = switch (builtin.os.tag) {
81	84	}
82	85
83	86	fn destroy(lfh: FileHandle, gpa: Allocator) void {
84		const ptr: [*]u8 = @ptrCast(lfh.handle);
	87	const ptr: [*]align(@alignOf(std.os.linux.file_handle)) u8 = @ptrCast(@alignCast(lfh.handle));
85	88	const allocated_slice = ptr[0 .. @sizeOf(std.os.linux.file_handle) + lfh.handle.handle_bytes];
86	89	return gpa.free(allocated_slice);
87	90	}
...	...	@@ -121,6 +124,24 @@ const Os = switch (builtin.os.tag) {
121	124	};
122	125	}
123	126
	127	fn deinit(w: *Watch) void {
	128	const gpa = w.maker.gpa;
	129
	130	for (w.os.handle_table.keys(), w.os.handle_table.values()) \|fh, *reaction\| {
	131	fh.destroy(gpa);
	132	reaction.reaction_set.deinit(gpa);
	133	}
	134	w.os.handle_table.deinit(gpa);
	135
	136	for (w.os.poll_fds.values()) \|pollfd\| {
	137	Io.Threaded.closeFd(pollfd.fd);
	138	}
	139	w.os.poll_fds.deinit(gpa);
	140
	141	w.dir_table.deinit(gpa);
	142	w.* = undefined;
	143	}
	144
124	145	fn getDirHandle(gpa: Allocator, path: std.Build.Cache.Path, mount_id: *MountId) !FileHandle {
125	146	var file_handle_buffer: [@sizeOf(std.os.linux.file_handle) + 128]u8 align(@alignOf(std.os.linux.file_handle)) = undefined;
126	147	var buf: [std.fs.max_path_bytes]u8 = undefined;
...	...	@@ -152,10 +173,8 @@ const Os = switch (builtin.os.tag) {
152	173	}) {
153	174	assert(meta[0].vers == M.VERSION);
154	175	if (meta[0].mask.Q_OVERFLOW) {
155		any_dirty = true;
156		std.log.warn("file system watch queue overflowed; falling back to fstat", .{});
157		markAllFilesDirty(w);
158		return true;
	176	std.log.warn("file system watch queue overflowed; reconfiguring", .{});
	177	return error.MustReconfigure;
159	178	}
160	179	const fid: *align(1) fanotify.event_info_fid = @ptrCast(meta + 1);
161	180	switch (fid.hdr.info_type) {
...	...	@@ -166,9 +185,9 @@ const Os = switch (builtin.os.tag) {
166	185	const lfh: FileHandle = .{ .handle = file_handle };
167	186	if (w.os.handle_table.getPtr(lfh)) \|value\| {
168	187	if (value.reaction_set.getPtr(".")) \|glob_set\|
169		any_dirty = markStepSetDirty(maker, glob_set, any_dirty);
	188	any_dirty = try markStepSetDirty(maker, glob_set, any_dirty);
170	189	if (value.reaction_set.getPtr(file_name)) \|step_set\|
171		any_dirty = markStepSetDirty(maker, step_set, any_dirty);
	190	any_dirty = try markStepSetDirty(maker, step_set, any_dirty);
172	191	}
173	192	},
174	193	else => \|t\| std.log.warn("unexpected fanotify event '{t}'", .{t}),
...	...	@@ -304,8 +323,11 @@ const Os = switch (builtin.os.tag) {
304	323	if (events_len == 0)
305	324	return .timeout;
306	325	for (w.os.poll_fds.values()) \|poll_fd\| {
307		if (poll_fd.revents & std.posix.POLL.IN == std.posix.POLL.IN and try markDirtySteps(w, poll_fd.fd))
	326	if (poll_fd.revents & std.posix.POLL.IN == std.posix.POLL.IN and
	327	try markDirtySteps(w, poll_fd.fd))
	328	{
308	329	return .dirty;
	330	}
309	331	}
310	332	return .clean;
311	333	}
...	...	@@ -361,7 +383,7 @@ const Os = switch (builtin.os.tag) {
361	383	}
362	384	}
363	385
364		fn notifyApc(apc_context: ?anyopaque, iosb: windows.IO_STATUS_BLOCK, _: windows.ULONG) align(std.Io.Threaded.apc_align) callconv(.winapi) void {
	386	fn notifyApc(apc_context: ?anyopaque, iosb: windows.IO_STATUS_BLOCK, _: windows.ULONG) align(Io.Threaded.apc_align) callconv(.winapi) void {
365	387	const w: *Watch = @ptrCast(@alignCast(apc_context));
366	388	const dir: *Directory = @fieldParentPtr("iosb", iosb);
367	389	assert(iosb.u.Status != .PENDING);
...	...	@@ -481,6 +503,18 @@ const Os = switch (builtin.os.tag) {
481	503	};
482	504	}
483	505
	506	fn deinit(w: *Watch) void {
	507	const gpa = w.maker.gpa;
	508
	509	for (w.os.handle_table.keys()) \|dir\| {
	510	dir.deinit(gpa, w);
	511	}
	512	w.os.handle_table.deinit(gpa);
	513
	514	w.dir_table.deinit(gpa);
	515	w.* = undefined;
	516	}
	517
484	518	fn getFileId(handle: windows.HANDLE) !FileId {
485	519	var file_id: FileId = undefined;
486	520	var io_status: windows.IO_STATUS_BLOCK = undefined;
...	...	@@ -521,10 +555,8 @@ const Os = switch (builtin.os.tag) {
521	555	var any_dirty = false;
522	556	const bytes_returned = dir.iosb.Information;
523	557	if (bytes_returned == 0) {
524		std.log.warn("file system watch queue overflowed; falling back to fstat", .{});
525		markAllFilesDirty(w);
526		try dir.startListening(w);
527		return true;
	558	std.log.warn("file system watch queue overflowed; reconfiguring", .{});
	559	return error.MustReconfigure;
528	560	}
529	561	var file_name_buf: [std.fs.max_path_bytes]u8 = undefined;
530	562	var offset: usize = 0;
...	...	@@ -532,9 +564,9 @@ const Os = switch (builtin.os.tag) {
532	564	const notify: *windows.FILE.NOTIFY.INFORMATION = @ptrCast(@alignCast(&dir.buffer[offset]));
533	565	const file_name = file_name_buf[0..std.unicode.wtf16LeToWtf8(&file_name_buf, notify.fileName())];
534	566	if (dir.reaction_set.getPtr(".")) \|glob_set\|
535		any_dirty = markStepSetDirty(maker, glob_set, any_dirty);
	567	any_dirty = try markStepSetDirty(maker, glob_set, any_dirty);
536	568	if (dir.reaction_set.getPtr(file_name)) \|step_set\|
537		any_dirty = markStepSetDirty(maker, step_set, any_dirty);
	569	any_dirty = try markStepSetDirty(maker, step_set, any_dirty);
538	570	if (notify.NextEntryOffset == 0)
539	571	break;
540	572
...	...	@@ -693,6 +725,21 @@ const Os = switch (builtin.os.tag) {
693	725	};
694	726	}
695	727
	728	fn deinit(w: *Watch) void {
	729	const gpa = w.maker.gpa;
	730
	731	for (w.os.handles.items(.rs), w.os.handles.items(.dir_fd)) \|*rs, dir_fd\| {
	732	rs.deinit(gpa);
	733	Io.Threaded.closeFd(dir_fd);
	734	}
	735	w.os.handles.deinit(gpa);
	736
	737	Io.Threaded.closeFd(w.os.kq_fd);
	738
	739	w.dir_table.deinit(gpa);
	740	w.* = undefined;
	741	}
	742
696	743	fn update(w: *Watch, steps: []const Configuration.Step.Index) !void {
697	744	const maker = w.maker;
698	745	const gpa = maker.gpa;
...	...	@@ -711,7 +758,7 @@ const Os = switch (builtin.os.tag) {
711	758	fatal("failed to open directory {f}: {t}", .{ path, err });
712	759	};
713	760	// Empirically the dir has to stay open or else no events are triggered.
714		errdefer if (!skip_open_dir) std.Io.Threaded.closeFd(dir_fd);
	761	errdefer if (!skip_open_dir) Io.Threaded.closeFd(dir_fd);
715	762	const changes = [1]posix.Kevent{.{
716	763	.ident = @bitCast(@as(isize, dir_fd)),
717	764	.filter = std.c.EVFILT.VNODE,
...	...	@@ -811,7 +858,7 @@ const Os = switch (builtin.os.tag) {
811	858	};
812	859	const filtered_changes = if (i == handles.len - 1) changes[0..1] else &changes;
813	860	_ = try Io.Kqueue.kevent(w.os.kq_fd, filtered_changes, &.{}, null);
814		if (path.sub_path.len != 0) std.Io.Threaded.closeFd(dir_fd);
	861	if (path.sub_path.len != 0) Io.Threaded.closeFd(dir_fd);
815	862
816	863	w.dir_table.swapRemoveAt(i);
817	864	handles.swapRemove(i);
...	...	@@ -828,12 +875,12 @@ const Os = switch (builtin.os.tag) {
828	875	var n = try Io.Kqueue.kevent(w.os.kq_fd, &.{}, &event_buffer, timeout.toTimespec(&timespec_buffer));
829	876	if (n == 0) return .timeout;
830	877	const reaction_sets = w.os.handles.items(.rs);
831		var any_dirty = markDirtySteps(maker, reaction_sets, event_buffer[0..n], false);
	878	var any_dirty = try markDirtySteps(maker, reaction_sets, event_buffer[0..n], false);
832	879	timespec_buffer = .{ .sec = 0, .nsec = 0 };
833	880	while (n == event_buffer.len) {
834	881	n = try Io.Kqueue.kevent(w.os.kq_fd, &.{}, &event_buffer, &timespec_buffer);
835	882	if (n == 0) break;
836		any_dirty = markDirtySteps(maker, reaction_sets, event_buffer[0..n], any_dirty);
	883	any_dirty = try markDirtySteps(maker, reaction_sets, event_buffer[0..n], any_dirty);
837	884	}
838	885	return if (any_dirty) .dirty else .clean;
839	886	}
...	...	@@ -843,7 +890,7 @@ const Os = switch (builtin.os.tag) {
843	890	reaction_sets: []ReactionSet,
844	891	events: []const std.c.Kevent,
845	892	start_any_dirty: bool,
846		) bool {
	893	) !bool {
847	894	var any_dirty = start_any_dirty;
848	895	for (events) \|event\| {
849	896	const index: usize = @intCast(event.udata);
...	...	@@ -851,13 +898,13 @@ const Os = switch (builtin.os.tag) {
851	898	// If we knew the basename of the changed file, here we would
852	899	// mark only the step set dirty, and possibly the glob set:
853	900	//if (reaction_set.getPtr(".")) \|glob_set\|
854		// any_dirty = markStepSetDirty(maker, glob_set, any_dirty);
	901	// any_dirty = try markStepSetDirty(maker, glob_set, any_dirty);
855	902	//if (reaction_set.getPtr(file_name)) \|step_set\|
856		// any_dirty = markStepSetDirty(maker, step_set, any_dirty);
	903	// any_dirty = try markStepSetDirty(maker, step_set, any_dirty);
857	904	// However we don't know the file name so just mark all the
858	905	// sets dirty for this directory.
859	906	for (reaction_set.values()) \|*step_set\| {
860		any_dirty = markStepSetDirty(maker, step_set, any_dirty);
	907	any_dirty = try markStepSetDirty(maker, step_set, any_dirty);
861	908	}
862	909	}
863	910	return any_dirty;
...	...	@@ -875,6 +922,12 @@ const Os = switch (builtin.os.tag) {
875	922	.maker = maker,
876	923	};
877	924	}
	925	fn deinit(w: *Watch) void {
	926	const gpa = w.maker.gpa;
	927	const io = w.maker.graph.io;
	928	w.os.fse.deinit(gpa, io);
	929	w.* = undefined;
	930	}
878	931	fn update(w: *Watch, steps: []const Configuration.Step.Index) !void {
879	932	try w.os.fse.setPaths(w.maker, steps);
880	933	w.dir_count = w.os.fse.watch_roots.len;
...	...	@@ -915,31 +968,11 @@ pub const Match = struct {
915	968	};
916	969	};
917	970
918		fn markAllFilesDirty(w: *Watch) void {
919		const maker = w.maker;
920
921		for (switch (builtin.os.tag) {
922		.windows => w.os.handle_table.keys(),
923		else => w.os.handle_table.values(),
924		}) \|item\| {
925		const reaction_set = switch (builtin.os.tag) {
926		.linux, .windows => item.reaction_set,
927		else => item,
928		};
929		for (reaction_set.values()) \|step_set\| {
930		for (step_set.keys()) \|step_index\| {
931		const step = maker.stepByIndex(step_index);
932		_ = maker.invalidateResult(step);
933		}
934		}
935		}
936		}
937
938		fn markStepSetDirty(maker: Maker, step_set: StepSet, any_dirty: bool) bool {
	971	fn markStepSetDirty(maker: Maker, step_set: StepSet, any_dirty: bool) error{MustReconfigure}!bool {
939	972	var this_any_dirty = false;
940	973	for (step_set.keys()) \|step_index\| {
941	974	const step = maker.stepByIndex(step_index);
942		if (maker.invalidateResult(step)) this_any_dirty = true;
	975	if (try maker.invalidateResult(step)) this_any_dirty = true;
943	976	}
944	977	return any_dirty or this_any_dirty;
945	978	}
...	...	@@ -984,6 +1017,11 @@ pub const WaitResult = enum {
984	1017	clean,
985	1018	};
986	1019
	1020	/// May return `error.MustReconfigure`.
987	1021	pub fn wait(w: *Watch, timeout: Timeout) !WaitResult {
988	1022	return Os.wait(w, timeout);
989	1023	}
	1024
	1025	pub fn deinit(w: *Watch) void {
	1026	Os.deinit(w);
	1027	}

lib/compiler/Maker/Watch/FsEvents.zig+28-8

...	...	@@ -46,6 +46,8 @@ since_event: FSEventStreamEventId,
46	46
47	47	cwd_path: []const u8,
48	48
	49	must_reconfigure: bool,
	50
49	51	/// All of the symbols we pull from the `dlopen`ed CoreServices framework. If any of these symbols
50	52	/// is not present, `init` will close the framework and return an error.
51	53	const ResolvedSymbols = struct {
...	...	@@ -104,13 +106,15 @@ pub fn init(cwd_path: []const u8) error{ OpenFrameworkFailed, MissingCoreService
104	106	// to notice any changes which happened during said work.
105	107	.since_event = resolved_symbols.FSEventsGetCurrentEventId(),
106	108	.cwd_path = cwd_path,
	109	.must_reconfigure = false,
107	110	};
108	111	}
109	112
110	113	pub fn deinit(fse: *FsEvents, gpa: Allocator, io: Io) void {
	114	_ = io;
111	115	fse.waiting_semaphore.as_object().release();
112	116	fse.dispatch_queue.as_object().release();
113		fse.core_services.close(io);
	117	fse.core_services.close();
114	118
115	119	gpa.free(fse.watch_roots);
116	120	fse.watch_paths.deinit(gpa);
...	...	@@ -211,7 +215,7 @@ pub fn setPaths(fse: FsEvents, maker: Maker, steps: []const std.Build.Configur
211	215	}
212	216	}
213	217
214		pub fn wait(fse: FsEvents, maker: Maker, timeout_ns: ?u64) error{ OutOfMemory, StartFailed }!Watch.WaitResult {
	218	pub fn wait(fse: FsEvents, maker: Maker, timeout_ns: ?u64) error{ OutOfMemory, StartFailed, MustReconfigure }!Watch.WaitResult {
215	219	if (fse.watch_roots.len == 0) @panic("nothing to watch");
216	220	const gpa = maker.gpa;
217	221
...	...	@@ -285,6 +289,7 @@ pub fn wait(fse: FsEvents, maker: Maker, timeout_ns: ?u64) error{ OutOfMemory,
285	289	const ns = timeout_ns orelse break :timeout .FOREVER;
286	290	break :timeout .time(.NOW, @intCast(ns));
287	291	});
	292	if (fse.must_reconfigure) return error.MustReconfigure;
288	293	return switch (result) {
289	294	0 => .dirty,
290	295	else => .timeout,
...	...	@@ -355,13 +360,23 @@ fn eventCallback(
355	360	false => {
356	361	if (fse.watch_paths.get(event_path)) \|steps\| {
357	362	assert(steps.len > 0);
358		if (invalidateSteps(maker, steps)) any_dirty = true;
	363	if (invalidateSteps(maker, steps) catch \|err\| switch (err) {
	364	error.MustReconfigure => {
	365	fse.must_reconfigure = true;
	366	break;
	367	},
	368	}) any_dirty = true;
359	369	}
360	370	if (std.fs.path.dirname(event_path)) \|event_dirname\| {
361	371	// Modifying '/foo/bar' triggers the watch on '/foo'.
362	372	if (fse.watch_paths.get(event_dirname)) \|steps\| {
363	373	assert(steps.len > 0);
364		if (invalidateSteps(maker, steps)) any_dirty = true;
	374	if (invalidateSteps(maker, steps) catch \|err\| switch (err) {
	375	error.MustReconfigure => {
	376	fse.must_reconfigure = true;
	377	break;
	378	},
	379	}) any_dirty = true;
365	380	}
366	381	}
367	382	},
...	...	@@ -374,13 +389,18 @@ fn eventCallback(
374	389	const changed_path = std.fs.path.dirname(event_path) orelse event_path;
375	390	for (fse.watch_paths.keys(), fse.watch_paths.values()) \|watching_path, steps\| {
376	391	if (dirStartsWith(watching_path, changed_path)) {
377		if (invalidateSteps(maker, steps)) any_dirty = true;
	392	if (invalidateSteps(maker, steps) catch \|err\| switch (err) {
	393	error.MustReconfigure => {
	394	fse.must_reconfigure = true;
	395	break;
	396	},
	397	}) any_dirty = true;
378	398	}
379	399	}
380	400	},
381	401	}
382	402	}
383		if (any_dirty) {
	403	if (any_dirty or fse.must_reconfigure) {
384	404	fse.since_event = rs.FSEventStreamGetLatestEventId(stream);
385	405	_ = fse.waiting_semaphore.signal();
386	406	}
...	...	@@ -392,11 +412,11 @@ fn dirStartsWith(path: []const u8, prefix: []const u8) bool {
392	412	return true; // `path` is `/foo/bar/...`, `prefix` is `/foo/bar`
393	413	}
394	414
395		fn invalidateSteps(maker: *Maker, steps: []const std.Build.Configuration.Step.Index) bool {
	415	fn invalidateSteps(maker: *Maker, steps: []const std.Build.Configuration.Step.Index) !bool {
396	416	var any_dirty = false;
397	417	for (steps) \|step_index\| {
398	418	const step = maker.stepByIndex(step_index);
399		if (maker.invalidateResult(step)) any_dirty = true;
	419	if (try maker.invalidateResult(step)) any_dirty = true;
400	420	}
401	421	return any_dirty;
402	422	}

lib/std/Build/Cache.zig+22-11

...	...	@@ -1,7 +1,7 @@
1		//! Manages `zig-cache` directories.
2		//! This is not a general-purpose cache. It is designed to be fast and simple,
3		//! not to withstand attacks using specially-crafted input.
4
	1	//! Tracks metadata of file inputs associated with Zig compiler and build
	2	//! system artifacts in order to determine whether those artifacts must be
	3	//! produced again, or may be retrieved from the cache directory on the
	4	//! filesystem.
5	5	const Cache = @This();
6	6	const builtin = @import("builtin");
7	7
...	...	@@ -1236,19 +1236,32 @@ pub const Manifest = struct {
1236	1236
1237	1237	/// Obtain only the data needed to maintain a lock on the manifest file.
1238	1238	/// The `Manifest` remains safe to deinit.
	1239	///
1239	1240	/// Don't forget to call `writeManifest` before this!
1240	1241	pub fn toOwnedLock(self: *Manifest) Lock {
1241	1242	defer self.manifest_file = null;
1242	1243	return .{ .manifest_file = self.manifest_file.? };
1243	1244	}
1244	1245
	1246	pub fn takeFiles(man: *Manifest) Files {
	1247	defer man.files = .empty;
	1248	return man.files;
	1249	}
	1250
	1251	pub fn freeFiles(gpa: Allocator, files: *Files) void {
	1252	for (files.keys()) \|*file\| file.deinit(gpa);
	1253	files.deinit(gpa);
	1254	}
	1255
1245	1256	/// Releases the manifest file and frees any memory the Manifest was using.
1246	1257	/// `Manifest.hit` must be called first.
	1258	///
1247	1259	/// Don't forget to call `writeManifest` before this!
1248		pub fn deinit(self: *Manifest) void {
1249		const io = self.cache.io;
	1260	pub fn deinit(man: *Manifest) void {
	1261	const io = man.cache.io;
	1262	const gpa = man.cache.gpa;
1250	1263
1251		if (self.manifest_file) \|file\| {
	1264	if (man.manifest_file) \|file\| {
1252	1265	if (builtin.os.tag == .windows) {
1253	1266	// See Lock.release for why this is required on Windows
1254	1267	file.unlock(io);
...	...	@@ -1256,10 +1269,8 @@ pub const Manifest = struct {
1256	1269
1257	1270	file.close(io);
1258	1271	}
1259		for (self.files.keys()) \|*file\| {
1260		file.deinit(self.cache.gpa);
1261		}
1262		self.files.deinit(self.cache.gpa);
	1272	freeFiles(gpa, &man.files);
	1273	man.* = undefined;
1263	1274	}
1264	1275
1265	1276	pub fn populateFileSystemInputs(man: Manifest, buf: std.ArrayList(u8)) Allocator.Error!void {

src/main.zig+1

...	...	@@ -5134,6 +5134,7 @@ fn jitCmdInner(
5134	5134	}
5135	5135
5136	5136	if (process.can_replace and options.capture == null) {
	5137	_ = try io.lockStderr(&.{}, .no_color);
5137	5138	const err = process.replace(io, .{ .argv = child_argv.items, .environ_map = environ_map });
5138	5139	const cmd = try std.mem.join(arena, " ", child_argv.items);
5139	5140	fatal("the following command failed to execve with {t}:\n{s}", .{ err, cmd });