commit d4623a8a07bf8fe3bed3b4ee50339960d623958e (tree)
parent a76775b50a65fd0ea0fd17d6ef3c42058df13997
Author: Jakub Konka <kubkon@jakubkonka.com>
Date: Tue, 28 Jun 2022 07:22:19 +0200
Merge pull request #11941 from ziglang/macho-stripping-dylibs
macho: handle `-dead_strip_dylibs`, `-needed-lx` and `-needed_framework x` flags
Diffstat:
20 files changed, 318 insertions(+), 100 deletions(-)
diff --git a/lib/std/build.zig b/lib/std/build.zig
@@ -11,7 +11,6 @@ const ArrayList = std.ArrayList;
const StringHashMap = std.StringHashMap;
const Allocator = mem.Allocator;
const process = std.process;
-const BufSet = std.BufSet;
const EnvMap = std.process.EnvMap;
const fmt_lib = std.fmt;
const File = std.fs.File;
@@ -1484,7 +1483,7 @@ pub const LibExeObjStep = struct {
lib_paths: ArrayList([]const u8),
rpaths: ArrayList([]const u8),
framework_dirs: ArrayList([]const u8),
- frameworks: BufSet,
+ frameworks: StringHashMap(bool),
verbose_link: bool,
verbose_cc: bool,
emit_analysis: EmitOption = .default,
@@ -1601,6 +1600,9 @@ pub const LibExeObjStep = struct {
/// and start of `__TEXT,__text` section to a value fitting all paths expanded to MAXPATHLEN.
headerpad_max_install_names: bool = false,
+ /// (Darwin) Remove dylibs that are unreachable by the entry point or exported symbols.
+ dead_strip_dylibs: bool = false,
+
/// Position Independent Code
force_pic: ?bool = null,
@@ -1640,6 +1642,7 @@ pub const LibExeObjStep = struct {
pub const SystemLib = struct {
name: []const u8,
+ needed: bool,
use_pkg_config: enum {
/// Don't use pkg-config, just pass -lfoo where foo is name.
no,
@@ -1741,7 +1744,7 @@ pub const LibExeObjStep = struct {
.kind = kind,
.root_src = root_src,
.name = name,
- .frameworks = BufSet.init(builder.allocator),
+ .frameworks = StringHashMap(bool).init(builder.allocator),
.step = Step.init(base_id, name, builder.allocator, make),
.version = ver,
.out_filename = undefined,
@@ -1890,8 +1893,11 @@ pub const LibExeObjStep = struct {
}
pub fn linkFramework(self: *LibExeObjStep, framework_name: []const u8) void {
- // Note: No need to dupe because frameworks dupes internally.
- self.frameworks.insert(framework_name) catch unreachable;
+ self.frameworks.put(self.builder.dupe(framework_name), false) catch unreachable;
+ }
+
+ pub fn linkFrameworkNeeded(self: *LibExeObjStep, framework_name: []const u8) void {
+ self.frameworks.put(self.builder.dupe(framework_name), true) catch unreachable;
}
/// Returns whether the library, executable, or object depends on a particular system library.
@@ -1932,6 +1938,7 @@ pub const LibExeObjStep = struct {
self.link_objects.append(.{
.system_lib = .{
.name = "c",
+ .needed = false,
.use_pkg_config = .no,
},
}) catch unreachable;
@@ -1944,6 +1951,7 @@ pub const LibExeObjStep = struct {
self.link_objects.append(.{
.system_lib = .{
.name = "c++",
+ .needed = false,
.use_pkg_config = .no,
},
}) catch unreachable;
@@ -1968,6 +1976,19 @@ pub const LibExeObjStep = struct {
self.link_objects.append(.{
.system_lib = .{
.name = self.builder.dupe(name),
+ .needed = false,
+ .use_pkg_config = .no,
+ },
+ }) catch unreachable;
+ }
+
+ /// This one has no integration with anything, it just puts -needed-lname on the command line.
+ /// Prefer to use `linkSystemLibraryNeeded` instead.
+ pub fn linkSystemLibraryNeededName(self: *LibExeObjStep, name: []const u8) void {
+ self.link_objects.append(.{
+ .system_lib = .{
+ .name = self.builder.dupe(name),
+ .needed = true,
.use_pkg_config = .no,
},
}) catch unreachable;
@@ -1979,6 +2000,19 @@ pub const LibExeObjStep = struct {
self.link_objects.append(.{
.system_lib = .{
.name = self.builder.dupe(lib_name),
+ .needed = false,
+ .use_pkg_config = .force,
+ },
+ }) catch unreachable;
+ }
+
+ /// This links against a system library, exclusively using pkg-config to find the library.
+ /// Prefer to use `linkSystemLibraryNeeded` instead.
+ pub fn linkSystemLibraryNeededPkgConfigOnly(self: *LibExeObjStep, lib_name: []const u8) void {
+ self.link_objects.append(.{
+ .system_lib = .{
+ .name = self.builder.dupe(lib_name),
+ .needed = true,
.use_pkg_config = .force,
},
}) catch unreachable;
@@ -2081,6 +2115,14 @@ pub const LibExeObjStep = struct {
}
pub fn linkSystemLibrary(self: *LibExeObjStep, name: []const u8) void {
+ self.linkSystemLibraryInner(name, false);
+ }
+
+ pub fn linkSystemLibraryNeeded(self: *LibExeObjStep, name: []const u8) void {
+ self.linkSystemLibraryInner(name, true);
+ }
+
+ fn linkSystemLibraryInner(self: *LibExeObjStep, name: []const u8, needed: bool) void {
if (isLibCLibrary(name)) {
self.linkLibC();
return;
@@ -2093,6 +2135,7 @@ pub const LibExeObjStep = struct {
self.link_objects.append(.{
.system_lib = .{
.name = self.builder.dupe(name),
+ .needed = needed,
.use_pkg_config = .yes,
},
}) catch unreachable;
@@ -2434,7 +2477,7 @@ pub const LibExeObjStep = struct {
if (!other.isDynamicLibrary()) {
var it = other.frameworks.iterator();
while (it.next()) |framework| {
- self.frameworks.insert(framework.*) catch unreachable;
+ self.frameworks.put(framework.key_ptr.*, framework.value_ptr.*) catch unreachable;
}
}
},
@@ -2470,8 +2513,9 @@ pub const LibExeObjStep = struct {
},
.system_lib => |system_lib| {
+ const prefix: []const u8 = if (system_lib.needed) "-needed-l" else "-l";
switch (system_lib.use_pkg_config) {
- .no => try zig_args.append(builder.fmt("-l{s}", .{system_lib.name})),
+ .no => try zig_args.append(builder.fmt("{s}{s}", .{ prefix, system_lib.name })),
.yes, .force => {
if (self.runPkgConfig(system_lib.name)) |args| {
try zig_args.appendSlice(args);
@@ -2485,7 +2529,10 @@ pub const LibExeObjStep = struct {
.yes => {
// pkg-config failed, so fall back to linking the library
// by name directly.
- try zig_args.append(builder.fmt("-l{s}", .{system_lib.name}));
+ try zig_args.append(builder.fmt("{s}{s}", .{
+ prefix,
+ system_lib.name,
+ }));
},
.force => {
panic("pkg-config failed for library {s}", .{system_lib.name});
@@ -2676,6 +2723,9 @@ pub const LibExeObjStep = struct {
if (self.headerpad_max_install_names) {
try zig_args.append("-headerpad_max_install_names");
}
+ if (self.dead_strip_dylibs) {
+ try zig_args.append("-dead_strip_dylibs");
+ }
if (self.bundle_compiler_rt) |x| {
if (x) {
@@ -2966,9 +3016,15 @@ pub const LibExeObjStep = struct {
}
var it = self.frameworks.iterator();
- while (it.next()) |framework| {
- zig_args.append("-framework") catch unreachable;
- zig_args.append(framework.*) catch unreachable;
+ while (it.next()) |entry| {
+ const name = entry.key_ptr.*;
+ const needed = entry.value_ptr.*;
+ if (needed) {
+ zig_args.append("-needed_framework") catch unreachable;
+ } else {
+ zig_args.append("-framework") catch unreachable;
+ }
+ zig_args.append(name) catch unreachable;
}
} else {
if (self.framework_dirs.items.len > 0) {
diff --git a/src/Compilation.zig b/src/Compilation.zig
@@ -791,7 +791,7 @@ pub const InitOptions = struct {
c_source_files: []const CSourceFile = &[0]CSourceFile{},
link_objects: []LinkObject = &[0]LinkObject{},
framework_dirs: []const []const u8 = &[0][]const u8{},
- frameworks: []const []const u8 = &[0][]const u8{},
+ frameworks: std.StringArrayHashMapUnmanaged(SystemLib) = .{},
system_lib_names: []const []const u8 = &.{},
system_lib_infos: []const SystemLib = &.{},
/// These correspond to the WASI libc emulated subcomponents including:
@@ -911,6 +911,8 @@ pub const InitOptions = struct {
headerpad_size: ?u32 = null,
/// (Darwin) set enough space as if all paths were MATPATHLEN
headerpad_max_install_names: bool = false,
+ /// (Darwin) remove dylibs that are unreachable by the entry point or exported symbols
+ dead_strip_dylibs: bool = false,
};
fn addPackageTableToCacheHash(
@@ -1095,7 +1097,7 @@ pub fn create(gpa: Allocator, options: InitOptions) !*Compilation {
// Our linker can't handle objects or most advanced options yet.
if (options.link_objects.len != 0 or
options.c_source_files.len != 0 or
- options.frameworks.len != 0 or
+ options.frameworks.count() != 0 or
options.system_lib_names.len != 0 or
options.link_libc or options.link_libcpp or
link_eh_frame_hdr or
@@ -1213,7 +1215,7 @@ pub fn create(gpa: Allocator, options: InitOptions) !*Compilation {
options.target,
options.is_native_abi,
link_libc,
- options.system_lib_names.len != 0 or options.frameworks.len != 0,
+ options.system_lib_names.len != 0 or options.frameworks.count() != 0,
options.libc_installation,
options.native_darwin_sdk != null,
);
@@ -1754,6 +1756,7 @@ pub fn create(gpa: Allocator, options: InitOptions) !*Compilation {
.search_strategy = options.search_strategy,
.headerpad_size = options.headerpad_size,
.headerpad_max_install_names = options.headerpad_max_install_names,
+ .dead_strip_dylibs = options.dead_strip_dylibs,
});
errdefer bin_file.destroy();
comp.* = .{
@@ -2369,7 +2372,7 @@ fn prepareWholeEmitSubPath(arena: Allocator, opt_emit: ?EmitLoc) error{OutOfMemo
/// to remind the programmer to update multiple related pieces of code that
/// are in different locations. Bump this number when adding or deleting
/// anything from the link cache manifest.
-pub const link_hash_implementation_version = 6;
+pub const link_hash_implementation_version = 7;
fn addNonIncrementalStuffToCacheManifest(comp: *Compilation, man: *Cache.Manifest) !void {
const gpa = comp.gpa;
@@ -2379,7 +2382,7 @@ fn addNonIncrementalStuffToCacheManifest(comp: *Compilation, man: *Cache.Manifes
defer arena_allocator.deinit();
const arena = arena_allocator.allocator();
- comptime assert(link_hash_implementation_version == 6);
+ comptime assert(link_hash_implementation_version == 7);
if (comp.bin_file.options.module) |mod| {
const main_zig_file = try mod.main_pkg.root_src_directory.join(arena, &[_][]const u8{
@@ -2482,12 +2485,13 @@ fn addNonIncrementalStuffToCacheManifest(comp: *Compilation, man: *Cache.Manifes
// Mach-O specific stuff
man.hash.addListOfBytes(comp.bin_file.options.framework_dirs);
- man.hash.addListOfBytes(comp.bin_file.options.frameworks);
+ link.hashAddSystemLibs(&man.hash, comp.bin_file.options.frameworks);
try man.addOptionalFile(comp.bin_file.options.entitlements);
man.hash.addOptional(comp.bin_file.options.pagezero_size);
man.hash.addOptional(comp.bin_file.options.search_strategy);
man.hash.addOptional(comp.bin_file.options.headerpad_size);
man.hash.add(comp.bin_file.options.headerpad_max_install_names);
+ man.hash.add(comp.bin_file.options.dead_strip_dylibs);
// COFF specific stuff
man.hash.addOptional(comp.bin_file.options.subsystem);
diff --git a/src/link.zig b/src/link.zig
@@ -162,7 +162,7 @@ pub const Options = struct {
objects: []Compilation.LinkObject,
framework_dirs: []const []const u8,
- frameworks: []const []const u8,
+ frameworks: std.StringArrayHashMapUnmanaged(SystemLib),
system_libs: std.StringArrayHashMapUnmanaged(SystemLib),
wasi_emulated_libs: []const wasi_libc.CRTFile,
lib_dirs: []const []const u8,
@@ -199,6 +199,9 @@ pub const Options = struct {
/// (Darwin) set enough space as if all paths were MATPATHLEN
headerpad_max_install_names: bool = false,
+ /// (Darwin) remove dylibs that are unreachable by the entry point or exported symbols
+ dead_strip_dylibs: bool = false,
+
pub fn effectiveOutputMode(options: Options) std.builtin.OutputMode {
return if (options.use_lld) .Obj else options.output_mode;
}
diff --git a/src/link/Coff.zig b/src/link/Coff.zig
@@ -969,7 +969,7 @@ fn linkWithLLD(self: *Coff, comp: *Compilation, prog_node: *std.Progress.Node) !
man = comp.cache_parent.obtain();
self.base.releaseLock();
- comptime assert(Compilation.link_hash_implementation_version == 6);
+ comptime assert(Compilation.link_hash_implementation_version == 7);
for (self.base.options.objects) |obj| {
_ = try man.addFile(obj.path, null);
diff --git a/src/link/Elf.zig b/src/link/Elf.zig
@@ -1298,7 +1298,7 @@ fn linkWithLLD(self: *Elf, comp: *Compilation, prog_node: *std.Progress.Node) !v
// We are about to obtain this lock, so here we give other processes a chance first.
self.base.releaseLock();
- comptime assert(Compilation.link_hash_implementation_version == 6);
+ comptime assert(Compilation.link_hash_implementation_version == 7);
try man.addOptionalFile(self.base.options.linker_script);
try man.addOptionalFile(self.base.options.version_script);
diff --git a/src/link/MachO.zig b/src/link/MachO.zig
@@ -541,7 +541,7 @@ pub fn flushModule(self: *MachO, comp: *Compilation, prog_node: *std.Progress.No
// We are about to obtain this lock, so here we give other processes a chance first.
self.base.releaseLock();
- comptime assert(Compilation.link_hash_implementation_version == 6);
+ comptime assert(Compilation.link_hash_implementation_version == 7);
for (self.base.options.objects) |obj| {
_ = try man.addFile(obj.path, null);
@@ -558,9 +558,10 @@ pub fn flushModule(self: *MachO, comp: *Compilation, prog_node: *std.Progress.No
man.hash.addOptional(self.base.options.search_strategy);
man.hash.addOptional(self.base.options.headerpad_size);
man.hash.add(self.base.options.headerpad_max_install_names);
+ man.hash.add(self.base.options.dead_strip_dylibs);
man.hash.addListOfBytes(self.base.options.lib_dirs);
man.hash.addListOfBytes(self.base.options.framework_dirs);
- man.hash.addListOfBytes(self.base.options.frameworks);
+ link.hashAddSystemLibs(&man.hash, self.base.options.frameworks);
man.hash.addListOfBytes(self.base.options.rpath_list);
if (is_dyn_lib) {
man.hash.addOptionalBytes(self.base.options.install_name);
@@ -767,19 +768,20 @@ pub fn flushModule(self: *MachO, comp: *Compilation, prog_node: *std.Progress.No
}
// Shared and static libraries passed via `-l` flag.
- var search_lib_names = std.ArrayList([]const u8).init(arena);
+ var candidate_libs = std.StringArrayHashMap(Compilation.SystemLib).init(arena);
- const system_libs = self.base.options.system_libs.keys();
- for (system_libs) |link_lib| {
+ const system_lib_names = self.base.options.system_libs.keys();
+ for (system_lib_names) |system_lib_name| {
// By this time, we depend on these libs being dynamically linked libraries and not static libraries
// (the check for that needs to be earlier), but they could be full paths to .dylib files, in which
// case we want to avoid prepending "-l".
- if (Compilation.classifyFileExt(link_lib) == .shared_library) {
- try positionals.append(link_lib);
+ if (Compilation.classifyFileExt(system_lib_name) == .shared_library) {
+ try positionals.append(system_lib_name);
continue;
}
- try search_lib_names.append(link_lib);
+ const system_lib_info = self.base.options.system_libs.get(system_lib_name).?;
+ try candidate_libs.put(system_lib_name, system_lib_info);
}
var lib_dirs = std.ArrayList([]const u8).init(arena);
@@ -791,18 +793,18 @@ pub fn flushModule(self: *MachO, comp: *Compilation, prog_node: *std.Progress.No
}
}
- var libs = std.ArrayList([]const u8).init(arena);
+ var libs = std.StringArrayHashMap(Compilation.SystemLib).init(arena);
// Assume ld64 default -search_paths_first if no strategy specified.
const search_strategy = self.base.options.search_strategy orelse .paths_first;
- outer: for (search_lib_names.items) |lib_name| {
+ outer: for (candidate_libs.keys()) |lib_name| {
switch (search_strategy) {
.paths_first => {
// Look in each directory for a dylib (stub first), and then for archive
for (lib_dirs.items) |dir| {
for (&[_][]const u8{ ".tbd", ".dylib", ".a" }) |ext| {
if (try resolveLib(arena, dir, lib_name, ext)) |full_path| {
- try libs.append(full_path);
+ try libs.put(full_path, candidate_libs.get(lib_name).?);
continue :outer;
}
}
@@ -816,13 +818,13 @@ pub fn flushModule(self: *MachO, comp: *Compilation, prog_node: *std.Progress.No
for (lib_dirs.items) |dir| {
for (&[_][]const u8{ ".tbd", ".dylib" }) |ext| {
if (try resolveLib(arena, dir, lib_name, ext)) |full_path| {
- try libs.append(full_path);
+ try libs.put(full_path, candidate_libs.get(lib_name).?);
continue :outer;
}
}
} else for (lib_dirs.items) |dir| {
if (try resolveLib(arena, dir, lib_name, ".a")) |full_path| {
- try libs.append(full_path);
+ try libs.put(full_path, candidate_libs.get(lib_name).?);
} else {
log.warn("library not found for '-l{s}'", .{lib_name});
lib_not_found = true;
@@ -846,7 +848,7 @@ pub fn flushModule(self: *MachO, comp: *Compilation, prog_node: *std.Progress.No
// re-exports every single symbol definition.
for (lib_dirs.items) |dir| {
if (try resolveLib(arena, dir, "System", ".tbd")) |full_path| {
- try libs.append(full_path);
+ try libs.put(full_path, .{ .needed = false });
libsystem_available = true;
break :blk;
}
@@ -856,8 +858,8 @@ pub fn flushModule(self: *MachO, comp: *Compilation, prog_node: *std.Progress.No
for (lib_dirs.items) |dir| {
if (try resolveLib(arena, dir, "System", ".dylib")) |libsystem_path| {
if (try resolveLib(arena, dir, "c", ".dylib")) |libc_path| {
- try libs.append(libsystem_path);
- try libs.append(libc_path);
+ try libs.put(libsystem_path, .{ .needed = false });
+ try libs.put(libc_path, .{ .needed = false });
libsystem_available = true;
break :blk;
}
@@ -871,7 +873,7 @@ pub fn flushModule(self: *MachO, comp: *Compilation, prog_node: *std.Progress.No
const full_path = try comp.zig_lib_directory.join(arena, &[_][]const u8{
"libc", "darwin", libsystem_name,
});
- try libs.append(full_path);
+ try libs.put(full_path, .{ .needed = false });
}
// frameworks
@@ -884,16 +886,16 @@ pub fn flushModule(self: *MachO, comp: *Compilation, prog_node: *std.Progress.No
}
}
- outer: for (self.base.options.frameworks) |framework| {
+ outer: for (self.base.options.frameworks.keys()) |f_name| {
for (framework_dirs.items) |dir| {
for (&[_][]const u8{ ".tbd", ".dylib", "" }) |ext| {
- if (try resolveFramework(arena, dir, framework, ext)) |full_path| {
- try libs.append(full_path);
+ if (try resolveFramework(arena, dir, f_name, ext)) |full_path| {
+ try libs.put(full_path, self.base.options.frameworks.get(f_name).?);
continue :outer;
}
}
} else {
- log.warn("framework not found for '-framework {s}'", .{framework});
+ log.warn("framework not found for '-framework {s}'", .{f_name});
framework_not_found = true;
}
}
@@ -987,6 +989,10 @@ pub fn flushModule(self: *MachO, comp: *Compilation, prog_node: *std.Progress.No
try argv.append("-headerpad_max_install_names");
}
+ if (self.base.options.dead_strip_dylibs) {
+ try argv.append("-dead_strip_dylibs");
+ }
+
if (self.base.options.entry) |entry| {
try argv.append("-e");
try argv.append(entry);
@@ -1020,15 +1026,25 @@ pub fn flushModule(self: *MachO, comp: *Compilation, prog_node: *std.Progress.No
try argv.append("-lc");
for (self.base.options.system_libs.keys()) |l_name| {
- try argv.append(try std.fmt.allocPrint(arena, "-l{s}", .{l_name}));
+ const needed = self.base.options.system_libs.get(l_name).?.needed;
+ const arg = if (needed)
+ try std.fmt.allocPrint(arena, "-needed-l{s}", .{l_name})
+ else
+ try std.fmt.allocPrint(arena, "-l{s}", .{l_name});
+ try argv.append(arg);
}
for (self.base.options.lib_dirs) |lib_dir| {
try argv.append(try std.fmt.allocPrint(arena, "-L{s}", .{lib_dir}));
}
- for (self.base.options.frameworks) |framework| {
- try argv.append(try std.fmt.allocPrint(arena, "-framework {s}", .{framework}));
+ for (self.base.options.frameworks.keys()) |framework| {
+ const needed = self.base.options.frameworks.get(framework).?.needed;
+ const arg = if (needed)
+ try std.fmt.allocPrint(arena, "-needed_framework {s}", .{framework})
+ else
+ try std.fmt.allocPrint(arena, "-framework {s}", .{framework});
+ try argv.append(arg);
}
for (self.base.options.framework_dirs) |framework_dir| {
@@ -1051,7 +1067,7 @@ pub fn flushModule(self: *MachO, comp: *Compilation, prog_node: *std.Progress.No
defer dependent_libs.deinit();
try self.parseInputFiles(positionals.items, self.base.options.sysroot, &dependent_libs);
try self.parseAndForceLoadStaticArchives(must_link_archives.keys());
- try self.parseLibs(libs.items, self.base.options.sysroot, &dependent_libs);
+ try self.parseLibs(libs.keys(), libs.values(), self.base.options.sysroot, &dependent_libs);
try self.parseDependentLibs(self.base.options.sysroot, &dependent_libs);
}
@@ -1376,6 +1392,7 @@ const DylibCreateOpts = struct {
dependent_libs: *std.fifo.LinearFifo(Dylib.Id, .Dynamic),
id: ?Dylib.Id = null,
is_dependent: bool = false,
+ is_needed: bool = false,
};
pub fn parseDylib(self: *MachO, path: []const u8, opts: DylibCreateOpts) ParseDylibError!bool {
@@ -1425,7 +1442,12 @@ pub fn parseDylib(self: *MachO, path: []const u8, opts: DylibCreateOpts) ParseDy
try self.dylibs.append(self.base.allocator, dylib);
try self.dylibs_map.putNoClobber(self.base.allocator, dylib.id.?.name, dylib_id);
- if (!(opts.is_dependent or self.referenced_dylibs.contains(dylib_id))) {
+ const should_link_dylib_even_if_unreachable = blk: {
+ if (self.base.options.dead_strip_dylibs and !opts.is_needed) break :blk false;
+ break :blk !(opts.is_dependent or self.referenced_dylibs.contains(dylib_id));
+ };
+
+ if (should_link_dylib_even_if_unreachable) {
try self.addLoadDylibLC(dylib_id);
try self.referenced_dylibs.putNoClobber(self.base.allocator, dylib_id, {});
}
@@ -1469,12 +1491,20 @@ fn parseAndForceLoadStaticArchives(self: *MachO, files: []const []const u8) !voi
}
}
-fn parseLibs(self: *MachO, libs: []const []const u8, syslibroot: ?[]const u8, dependent_libs: anytype) !void {
- for (libs) |lib| {
+fn parseLibs(
+ self: *MachO,
+ lib_names: []const []const u8,
+ lib_infos: []const Compilation.SystemLib,
+ syslibroot: ?[]const u8,
+ dependent_libs: anytype,
+) !void {
+ for (lib_names) |lib, i| {
+ const lib_info = lib_infos[i];
log.debug("parsing lib path '{s}'", .{lib});
if (try self.parseDylib(lib, .{
.syslibroot = syslibroot,
.dependent_libs = dependent_libs,
+ .is_needed = lib_info.needed,
})) continue;
if (try self.parseArchive(lib, false)) continue;
diff --git a/src/link/Wasm.zig b/src/link/Wasm.zig
@@ -2546,7 +2546,7 @@ fn linkWithLLD(self: *Wasm, comp: *Compilation, prog_node: *std.Progress.Node) !
// We are about to obtain this lock, so here we give other processes a chance first.
self.base.releaseLock();
- comptime assert(Compilation.link_hash_implementation_version == 6);
+ comptime assert(Compilation.link_hash_implementation_version == 7);
for (self.base.options.objects) |obj| {
_ = try man.addFile(obj.path, null);
diff --git a/src/main.zig b/src/main.zig
@@ -444,6 +444,8 @@ const usage_build_generic =
\\ --stack [size] Override default stack size
\\ --image-base [addr] Set base address for executable image
\\ -framework [name] (Darwin) link against framework
+ \\ -needed_framework [name] (Darwin) link against framework (even if unused)
+ \\ -needed_library [lib] (Darwin) link against system library (even if unused)
\\ -F[dir] (Darwin) add search path for frameworks
\\ -install_name=[value] (Darwin) add dylib's install name
\\ --entitlements [path] (Darwin) add path to entitlements file for embedding in code signature
@@ -452,6 +454,7 @@ const usage_build_generic =
\\ -search_dylibs_first (Darwin) search `libx.dylib` in each dir in library search paths, then `libx.a`
\\ -headerpad [value] (Darwin) set minimum space for future expansion of the load commands in hexadecimal notation
\\ -headerpad_max_install_names (Darwin) set enough space as if all paths were MAXPATHLEN
+ \\ -dead_strip_dylibs (Darwin) remove dylibs that are unreachable by the entry point or exported symbols
\\ --import-memory (WebAssembly) import memory from the environment
\\ --import-table (WebAssembly) import function table from the host environment
\\ --export-table (WebAssembly) export function table to the host environment
@@ -703,6 +706,7 @@ fn buildOutputType(
var search_strategy: ?link.File.MachO.SearchStrategy = null;
var headerpad_size: ?u32 = null;
var headerpad_max_install_names: bool = false;
+ var dead_strip_dylibs: bool = false;
// e.g. -m3dnow or -mno-outline-atomics. They correspond to std.Target llvm cpu feature names.
// This array is populated by zig cc frontend and then has to be converted to zig-style
@@ -748,8 +752,7 @@ fn buildOutputType(
var framework_dirs = std.ArrayList([]const u8).init(gpa);
defer framework_dirs.deinit();
- var frameworks = std.ArrayList([]const u8).init(gpa);
- defer frameworks.deinit();
+ var frameworks: std.StringArrayHashMapUnmanaged(Compilation.SystemLib) = .{};
// null means replace with the test executable binary
var test_exec_args = std.ArrayList(?[]const u8).init(gpa);
@@ -910,9 +913,15 @@ fn buildOutputType(
fatal("expected parameter after {s}", .{arg});
});
} else if (mem.eql(u8, arg, "-framework")) {
- try frameworks.append(args_iter.next() orelse {
+ const path = args_iter.next() orelse {
fatal("expected parameter after {s}", .{arg});
- });
+ };
+ try frameworks.put(gpa, path, .{ .needed = false });
+ } else if (mem.eql(u8, arg, "-needed_framework")) {
+ const path = args_iter.next() orelse {
+ fatal("expected parameter after {s}", .{arg});
+ };
+ try frameworks.put(gpa, path, .{ .needed = true });
} else if (mem.eql(u8, arg, "-install_name")) {
install_name = args_iter.next() orelse {
fatal("expected parameter after {s}", .{arg});
@@ -937,6 +946,8 @@ fn buildOutputType(
};
} else if (mem.eql(u8, arg, "-headerpad_max_install_names")) {
headerpad_max_install_names = true;
+ } else if (mem.eql(u8, arg, "-dead_strip_dylibs")) {
+ dead_strip_dylibs = true;
} else if (mem.eql(u8, arg, "-T") or mem.eql(u8, arg, "--script")) {
linker_script = args_iter.next() orelse {
fatal("expected parameter after {s}", .{arg});
@@ -952,7 +963,10 @@ fn buildOutputType(
// We don't know whether this library is part of libc or libc++ until
// we resolve the target, so we simply append to the list for now.
try system_libs.put(next_arg, .{ .needed = false });
- } else if (mem.eql(u8, arg, "--needed-library") or mem.eql(u8, arg, "-needed-l")) {
+ } else if (mem.eql(u8, arg, "--needed-library") or
+ mem.eql(u8, arg, "-needed-l") or
+ mem.eql(u8, arg, "--needed_library"))
+ {
const next_arg = args_iter.next() orelse {
fatal("expected parameter after {s}", .{arg});
};
@@ -1582,7 +1596,7 @@ fn buildOutputType(
try clang_argv.appendSlice(it.other_args);
},
.framework_dir => try framework_dirs.append(it.only_arg),
- .framework => try frameworks.append(it.only_arg),
+ .framework => try frameworks.put(gpa, it.only_arg, .{ .needed = false }),
.nostdlibinc => want_native_include_dirs = false,
.strip => strip = true,
.exec_model => {
@@ -1700,6 +1714,8 @@ fn buildOutputType(
};
} else if (mem.eql(u8, arg, "-headerpad_max_install_names")) {
headerpad_max_install_names = true;
+ } else if (mem.eql(u8, arg, "-dead_strip_dylibs")) {
+ dead_strip_dylibs = true;
} else if (mem.eql(u8, arg, "--gc-sections")) {
linker_gc_sections = true;
} else if (mem.eql(u8, arg, "--no-gc-sections")) {
@@ -1868,7 +1884,19 @@ fn buildOutputType(
if (i >= linker_args.items.len) {
fatal("expected linker arg after '{s}'", .{arg});
}
- try frameworks.append(linker_args.items[i]);
+ try frameworks.put(gpa, linker_args.items[i], .{ .needed = false });
+ } else if (mem.eql(u8, arg, "-needed_framework")) {
+ i += 1;
+ if (i >= linker_args.items.len) {
+ fatal("expected linker arg after '{s}'", .{arg});
+ }
+ try frameworks.put(gpa, linker_args.items[i], .{ .needed = true });
+ } else if (mem.eql(u8, arg, "-needed_library")) {
+ i += 1;
+ if (i >= linker_args.items.len) {
+ fatal("expected linker arg after '{s}'", .{arg});
+ }
+ try system_libs.put(linker_args.items[i], .{ .needed = true });
} else if (mem.eql(u8, arg, "-compatibility_version")) {
i += 1;
if (i >= linker_args.items.len) {
@@ -2238,7 +2266,7 @@ fn buildOutputType(
if (comptime builtin.target.isDarwin()) {
// If we want to link against frameworks, we need system headers.
- if (framework_dirs.items.len > 0 or frameworks.items.len > 0)
+ if (framework_dirs.items.len > 0 or frameworks.count() > 0)
want_native_include_dirs = true;
}
@@ -2728,7 +2756,7 @@ fn buildOutputType(
.c_source_files = c_source_files.items,
.link_objects = link_objects.items,
.framework_dirs = framework_dirs.items,
- .frameworks = frameworks.items,
+ .frameworks = frameworks,
.system_lib_names = system_libs.keys(),
.system_lib_infos = system_libs.values(),
.wasi_emulated_libs = wasi_emulated_libs.items,
@@ -2821,6 +2849,7 @@ fn buildOutputType(
.search_strategy = search_strategy,
.headerpad_size = headerpad_size,
.headerpad_max_install_names = headerpad_max_install_names,
+ .dead_strip_dylibs = dead_strip_dylibs,
}) catch |err| switch (err) {
error.LibCUnavailable => {
const target = target_info.target;
diff --git a/test/link.zig b/test/link.zig
@@ -40,7 +40,16 @@ pub fn addCases(cases: *tests.StandaloneContext) void {
.build_modes = true,
});
- cases.addBuildFile("test/link/macho/frameworks/build.zig", .{
+ cases.addBuildFile("test/link/macho/dead_strip_dylibs/build.zig", .{
+ .build_modes = true,
+ .requires_macos_sdk = true,
+ });
+
+ cases.addBuildFile("test/link/macho/needed_l/build.zig", .{
+ .build_modes = true,
+ });
+
+ cases.addBuildFile("test/link/macho/needed_framework/build.zig", .{
.build_modes = true,
.requires_macos_sdk = true,
});
diff --git a/test/link/macho/dead_strip_dylibs/build.zig b/test/link/macho/dead_strip_dylibs/build.zig
@@ -0,0 +1,46 @@
+const std = @import("std");
+const Builder = std.build.Builder;
+const LibExeObjectStep = std.build.LibExeObjStep;
+
+pub fn build(b: *Builder) void {
+ const mode = b.standardReleaseOptions();
+
+ const test_step = b.step("test", "Test the program");
+ test_step.dependOn(b.getInstallStep());
+
+ {
+ // Without -dead_strip_dylibs we expect `-la` to include liba.dylib in the final executable
+ const exe = createScenario(b, mode);
+
+ const check = exe.checkObject(.macho);
+ check.checkStart("cmd LOAD_DYLIB");
+ check.checkNext("name {*}Cocoa");
+
+ check.checkStart("cmd LOAD_DYLIB");
+ check.checkNext("name {*}libobjc{*}.dylib");
+
+ test_step.dependOn(&check.step);
+
+ const run_cmd = exe.run();
+ test_step.dependOn(&run_cmd.step);
+ }
+
+ {
+ // With -dead_strip_dylibs, we should include liba.dylib as it's unreachable
+ const exe = createScenario(b, mode);
+ exe.dead_strip_dylibs = true;
+
+ const run_cmd = exe.run();
+ run_cmd.expected_exit_code = @bitCast(u8, @as(i8, -2)); // should fail
+ test_step.dependOn(&run_cmd.step);
+ }
+}
+
+fn createScenario(b: *Builder, mode: std.builtin.Mode) *LibExeObjectStep {
+ const exe = b.addExecutable("test", null);
+ exe.addCSourceFile("main.c", &[0][]const u8{});
+ exe.setBuildMode(mode);
+ exe.linkLibC();
+ exe.linkFramework("Cocoa");
+ return exe;
+}
diff --git a/test/link/macho/dead_strip_dylibs/main.c b/test/link/macho/dead_strip_dylibs/main.c
@@ -0,0 +1,11 @@
+#include <objc/runtime.h>
+
+int main(int argc, char* argv[]) {
+ if (objc_getClass("NSObject") == 0) {
+ return -1;
+ }
+ if (objc_getClass("NSApplication") == 0) {
+ return -2;
+ }
+ return 0;
+}
diff --git a/test/link/macho/dylib/main.c b/test/link/macho/dylib/main.c
@@ -3,7 +3,7 @@
char* hello();
extern char world[];
-int main() {
+int main(int argc, char* argv[]) {
printf("%s %s", hello(), world);
return 0;
}
diff --git a/test/link/macho/frameworks/build.zig b/test/link/macho/frameworks/build.zig
@@ -1,32 +0,0 @@
-const std = @import("std");
-const Builder = std.build.Builder;
-
-pub fn build(b: *Builder) void {
- const mode = b.standardReleaseOptions();
-
- const test_step = b.step("test", "Test the program");
-
- const exe = b.addExecutable("test", null);
- b.default_step.dependOn(&exe.step);
- exe.addCSourceFile("main.c", &[0][]const u8{});
- exe.setBuildMode(mode);
- exe.linkLibC();
- exe.linkFramework("Cocoa");
-
- const check = exe.checkObject(.macho);
- check.checkStart("cmd LOAD_DYLIB");
- check.checkNext("name {*}Cocoa");
-
- switch (mode) {
- .Debug, .ReleaseSafe => {
- check.checkStart("cmd LOAD_DYLIB");
- check.checkNext("name {*}libobjc{*}.dylib");
- },
- else => {},
- }
-
- test_step.dependOn(&check.step);
-
- const run_cmd = exe.run();
- test_step.dependOn(&run_cmd.step);
-}
diff --git a/test/link/macho/frameworks/main.c b/test/link/macho/frameworks/main.c
@@ -1,7 +0,0 @@
-#include <assert.h>
-#include <objc/runtime.h>
-
-int main() {
- assert(objc_getClass("NSObject") > 0);
- assert(objc_getClass("NSApplication") > 0);
-}
diff --git a/test/link/macho/needed_framework/build.zig b/test/link/macho/needed_framework/build.zig
@@ -0,0 +1,27 @@
+const std = @import("std");
+const Builder = std.build.Builder;
+const LibExeObjectStep = std.build.LibExeObjStep;
+
+pub fn build(b: *Builder) void {
+ const mode = b.standardReleaseOptions();
+
+ const test_step = b.step("test", "Test the program");
+ test_step.dependOn(b.getInstallStep());
+
+ // -dead_strip_dylibs
+ // -needed_framework Cocoa
+ const exe = b.addExecutable("test", null);
+ exe.addCSourceFile("main.c", &[0][]const u8{});
+ exe.setBuildMode(mode);
+ exe.linkLibC();
+ exe.linkFrameworkNeeded("Cocoa");
+ exe.dead_strip_dylibs = true;
+
+ const check = exe.checkObject(.macho);
+ check.checkStart("cmd LOAD_DYLIB");
+ check.checkNext("name {*}Cocoa");
+ test_step.dependOn(&check.step);
+
+ const run_cmd = exe.run();
+ test_step.dependOn(&run_cmd.step);
+}
diff --git a/test/link/macho/needed_framework/main.c b/test/link/macho/needed_framework/main.c
@@ -0,0 +1,3 @@
+int main(int argc, char* argv[]) {
+ return 0;
+}
diff --git a/test/link/macho/needed_l/a.c b/test/link/macho/needed_l/a.c
@@ -0,0 +1 @@
+int a = 42;
diff --git a/test/link/macho/needed_l/build.zig b/test/link/macho/needed_l/build.zig
@@ -0,0 +1,35 @@
+const std = @import("std");
+const Builder = std.build.Builder;
+const LibExeObjectStep = std.build.LibExeObjStep;
+
+pub fn build(b: *Builder) void {
+ const mode = b.standardReleaseOptions();
+
+ const test_step = b.step("test", "Test the program");
+ test_step.dependOn(b.getInstallStep());
+
+ const dylib = b.addSharedLibrary("a", null, b.version(1, 0, 0));
+ dylib.setBuildMode(mode);
+ dylib.addCSourceFile("a.c", &.{});
+ dylib.linkLibC();
+ dylib.install();
+
+ // -dead_strip_dylibs
+ // -needed-la
+ const exe = b.addExecutable("test", null);
+ exe.addCSourceFile("main.c", &[0][]const u8{});
+ exe.setBuildMode(mode);
+ exe.linkLibC();
+ exe.linkSystemLibraryNeeded("a");
+ exe.addLibraryPath(b.pathFromRoot("zig-out/lib"));
+ exe.addRPath(b.pathFromRoot("zig-out/lib"));
+ exe.dead_strip_dylibs = true;
+
+ const check = exe.checkObject(.macho);
+ check.checkStart("cmd LOAD_DYLIB");
+ check.checkNext("name @rpath/liba.dylib");
+ test_step.dependOn(&check.step);
+
+ const run_cmd = exe.run();
+ test_step.dependOn(&run_cmd.step);
+}
diff --git a/test/link/macho/needed_l/main.c b/test/link/macho/needed_l/main.c
@@ -0,0 +1,3 @@
+int main(int argc, char* argv[]) {
+ return 0;
+}
diff --git a/test/link/macho/search_strategy/main.c b/test/link/macho/search_strategy/main.c
@@ -3,7 +3,7 @@
char* hello();
extern char world[];
-int main() {
+int main(int argc, char* argv[]) {
printf("%s %s", hello(), world);
return 0;
}
