authorgravatar for motiejus@jakstys.ltMotiejus Jakštys <motiejus@jakstys.lt> 2022-06-16 15:42:35+03:00
committergravatar for kubkon@jakubkonka.comJakub Konka <kubkon@jakubkonka.com> 2022-06-20 13:39:33+02:00
log98138ba78c1540830a4fdb0537ed6ad5c7b57e7a
tree8ff0a80295d0702fbe63bf8849c4b390ba94bd50
parenta97a39bea6022fb7449620384641cdfa70303f8d

[MachO] add -pagezero_size

Pass `-pagezero_size` to the MachO linker. This is the final "unsupported linker arg" that I could chase that CGo uses. After this and #11874 we may be able to fail on an "unsupported linker arg" instead of emiting a warning. Test case: zig=/code/zig/build/zig CGO_ENABLED=1 GOOS=darwin GOARCH=amd64 CC="$zig cc -target x86_64-macos" CXX="$zig c++ -target x86_64-macos" go build -a -ldflags "-s -w" cgo.go I compiled a trivial CGo program and executed it on an amd64 Darwin host. To be honest, I am not entirely sure what this is doing. This feels right after reading what this argument does in LLVM sources, but I am by no means qualified to make MachO pull requests. Will take feedback.

7 files changed, 29 insertions(+), 10 deletions(-)

src/Compilation.zig+5-2
...@@ -903,6 +903,8 @@ pub const InitOptions = struct {...@@ -903,6 +903,8 @@ pub const InitOptions = struct {
903 install_name: ?[]const u8 = null,903 install_name: ?[]const u8 = null,
904 /// (Darwin) Path to entitlements file904 /// (Darwin) Path to entitlements file
905 entitlements: ?[]const u8 = null,905 entitlements: ?[]const u8 = null,
906 /// (Darwin) size of the __PAGEZERO segment
907 pagezero_size: ?u64 = null,
906};908};
907909
908fn addPackageTableToCacheHash(910fn addPackageTableToCacheHash(
...@@ -2359,7 +2361,7 @@ fn prepareWholeEmitSubPath(arena: Allocator, opt_emit: ?EmitLoc) error{OutOfMemo...@@ -2359,7 +2361,7 @@ fn prepareWholeEmitSubPath(arena: Allocator, opt_emit: ?EmitLoc) error{OutOfMemo
2359/// to remind the programmer to update multiple related pieces of code that2361/// to remind the programmer to update multiple related pieces of code that
2360/// are in different locations. Bump this number when adding or deleting2362/// are in different locations. Bump this number when adding or deleting
2361/// anything from the link cache manifest.2363/// anything from the link cache manifest.
2362pub const link_hash_implementation_version = 3;2364pub const link_hash_implementation_version = 4;
23632365
2364fn addNonIncrementalStuffToCacheManifest(comp: *Compilation, man: *Cache.Manifest) !void {2366fn addNonIncrementalStuffToCacheManifest(comp: *Compilation, man: *Cache.Manifest) !void {
2365 const gpa = comp.gpa;2367 const gpa = comp.gpa;
...@@ -2369,7 +2371,7 @@ fn addNonIncrementalStuffToCacheManifest(comp: *Compilation, man: *Cache.Manifes...@@ -2369,7 +2371,7 @@ fn addNonIncrementalStuffToCacheManifest(comp: *Compilation, man: *Cache.Manifes
2369 defer arena_allocator.deinit();2371 defer arena_allocator.deinit();
2370 const arena = arena_allocator.allocator();2372 const arena = arena_allocator.allocator();
23712373
2372 comptime assert(link_hash_implementation_version == 3);2374 comptime assert(link_hash_implementation_version == 4);
23732375
2374 if (comp.bin_file.options.module) |mod| {2376 if (comp.bin_file.options.module) |mod| {
2375 const main_zig_file = try mod.main_pkg.root_src_directory.join(arena, &[_][]const u8{2377 const main_zig_file = try mod.main_pkg.root_src_directory.join(arena, &[_][]const u8{
...@@ -2474,6 +2476,7 @@ fn addNonIncrementalStuffToCacheManifest(comp: *Compilation, man: *Cache.Manifes...@@ -2474,6 +2476,7 @@ fn addNonIncrementalStuffToCacheManifest(comp: *Compilation, man: *Cache.Manifes
2474 man.hash.addListOfBytes(comp.bin_file.options.framework_dirs);2476 man.hash.addListOfBytes(comp.bin_file.options.framework_dirs);
2475 man.hash.addListOfBytes(comp.bin_file.options.frameworks);2477 man.hash.addListOfBytes(comp.bin_file.options.frameworks);
2476 try man.addOptionalFile(comp.bin_file.options.entitlements);2478 try man.addOptionalFile(comp.bin_file.options.entitlements);
2479 if (comp.bin_file.options.pagezero_size) |value| man.hash.add(value);
24772480
2478 // COFF specific stuff2481 // COFF specific stuff
2479 man.hash.addOptional(comp.bin_file.options.subsystem);2482 man.hash.addOptional(comp.bin_file.options.subsystem);
src/link.zig+3
...@@ -187,6 +187,9 @@ pub const Options = struct {...@@ -187,6 +187,9 @@ pub const Options = struct {
187 /// (Darwin) Path to entitlements file187 /// (Darwin) Path to entitlements file
188 entitlements: ?[]const u8 = null,188 entitlements: ?[]const u8 = null,
189189
190 /// (Darwin) size of the __PAGEZERO segment
191 pagezero_size: ?u64 = null,
192
190 pub fn effectiveOutputMode(options: Options) std.builtin.OutputMode {193 pub fn effectiveOutputMode(options: Options) std.builtin.OutputMode {
191 return if (options.use_lld) .Obj else options.output_mode;194 return if (options.use_lld) .Obj else options.output_mode;
192 }195 }
src/link/Coff.zig+1-1
...@@ -969,7 +969,7 @@ fn linkWithLLD(self: *Coff, comp: *Compilation, prog_node: *std.Progress.Node) !...@@ -969,7 +969,7 @@ fn linkWithLLD(self: *Coff, comp: *Compilation, prog_node: *std.Progress.Node) !
969 man = comp.cache_parent.obtain();969 man = comp.cache_parent.obtain();
970 self.base.releaseLock();970 self.base.releaseLock();
971971
972 comptime assert(Compilation.link_hash_implementation_version == 3);972 comptime assert(Compilation.link_hash_implementation_version == 4);
973973
974 for (self.base.options.objects) |obj| {974 for (self.base.options.objects) |obj| {
975 _ = try man.addFile(obj.path, null);975 _ = try man.addFile(obj.path, null);
src/link/Elf.zig+1-1
...@@ -1298,7 +1298,7 @@ fn linkWithLLD(self: *Elf, comp: *Compilation, prog_node: *std.Progress.Node) !v...@@ -1298,7 +1298,7 @@ fn linkWithLLD(self: *Elf, comp: *Compilation, prog_node: *std.Progress.Node) !v
1298 // We are about to obtain this lock, so here we give other processes a chance first.1298 // We are about to obtain this lock, so here we give other processes a chance first.
1299 self.base.releaseLock();1299 self.base.releaseLock();
13001300
1301 comptime assert(Compilation.link_hash_implementation_version == 3);1301 comptime assert(Compilation.link_hash_implementation_version == 4);
13021302
1303 try man.addOptionalFile(self.base.options.linker_script);1303 try man.addOptionalFile(self.base.options.linker_script);
1304 try man.addOptionalFile(self.base.options.version_script);1304 try man.addOptionalFile(self.base.options.version_script);
src/link/MachO.zig+6-5
...@@ -286,8 +286,8 @@ const default_dyld_path: [*:0]const u8 = "/usr/lib/dyld";...@@ -286,8 +286,8 @@ const default_dyld_path: [*:0]const u8 = "/usr/lib/dyld";
286const minimum_text_block_size = 64;286const minimum_text_block_size = 64;
287pub const min_text_capacity = padToIdeal(minimum_text_block_size);287pub const min_text_capacity = padToIdeal(minimum_text_block_size);
288288
289/// Virtual memory offset corresponds to the size of __PAGEZERO segment and start of289/// Virtual memory offset corresponds to the size of __PAGEZERO segment and
290/// __TEXT segment.290/// start of __TEXT segment.
291const pagezero_vmsize: u64 = 0x100000000;291const pagezero_vmsize: u64 = 0x100000000;
292292
293pub const Export = struct {293pub const Export = struct {
...@@ -536,7 +536,7 @@ pub fn flushModule(self: *MachO, comp: *Compilation, prog_node: *std.Progress.No...@@ -536,7 +536,7 @@ pub fn flushModule(self: *MachO, comp: *Compilation, prog_node: *std.Progress.No
536 // We are about to obtain this lock, so here we give other processes a chance first.536 // We are about to obtain this lock, so here we give other processes a chance first.
537 self.base.releaseLock();537 self.base.releaseLock();
538538
539 comptime assert(Compilation.link_hash_implementation_version == 3);539 comptime assert(Compilation.link_hash_implementation_version == 4);
540540
541 for (self.base.options.objects) |obj| {541 for (self.base.options.objects) |obj| {
542 _ = try man.addFile(obj.path, null);542 _ = try man.addFile(obj.path, null);
...@@ -549,6 +549,7 @@ pub fn flushModule(self: *MachO, comp: *Compilation, prog_node: *std.Progress.No...@@ -549,6 +549,7 @@ pub fn flushModule(self: *MachO, comp: *Compilation, prog_node: *std.Progress.No
549 // We can skip hashing libc and libc++ components that we are in charge of building from Zig549 // We can skip hashing libc and libc++ components that we are in charge of building from Zig
550 // installation sources because they are always a product of the compiler version + target information.550 // installation sources because they are always a product of the compiler version + target information.
551 man.hash.add(stack_size);551 man.hash.add(stack_size);
552 if (self.base.options.pagezero_size) |value| man.hash.add(value);
552 man.hash.addListOfBytes(self.base.options.lib_dirs);553 man.hash.addListOfBytes(self.base.options.lib_dirs);
553 man.hash.addListOfBytes(self.base.options.framework_dirs);554 man.hash.addListOfBytes(self.base.options.framework_dirs);
554 man.hash.addListOfBytes(self.base.options.frameworks);555 man.hash.addListOfBytes(self.base.options.frameworks);
...@@ -4372,7 +4373,7 @@ fn populateMissingMetadata(self: *MachO) !void {...@@ -4372,7 +4373,7 @@ fn populateMissingMetadata(self: *MachO) !void {
4372 .segment = .{4373 .segment = .{
4373 .inner = .{4374 .inner = .{
4374 .segname = makeStaticString("__PAGEZERO"),4375 .segname = makeStaticString("__PAGEZERO"),
4375 .vmsize = pagezero_vmsize,4376 .vmsize = self.base.options.pagezero_size orelse pagezero_vmsize,
4376 .cmdsize = @sizeOf(macho.segment_command_64),4377 .cmdsize = @sizeOf(macho.segment_command_64),
4377 },4378 },
4378 },4379 },
...@@ -4394,7 +4395,7 @@ fn populateMissingMetadata(self: *MachO) !void {...@@ -4394,7 +4395,7 @@ fn populateMissingMetadata(self: *MachO) !void {
4394 .segment = .{4395 .segment = .{
4395 .inner = .{4396 .inner = .{
4396 .segname = makeStaticString("__TEXT"),4397 .segname = makeStaticString("__TEXT"),
4397 .vmaddr = pagezero_vmsize,4398 .vmaddr = self.base.options.pagezero_size orelse pagezero_vmsize,
4398 .vmsize = needed_size,4399 .vmsize = needed_size,
4399 .filesize = needed_size,4400 .filesize = needed_size,
4400 .maxprot = macho.PROT.READ | macho.PROT.EXEC,4401 .maxprot = macho.PROT.READ | macho.PROT.EXEC,
src/link/Wasm.zig+1-1
...@@ -2274,7 +2274,7 @@ fn linkWithLLD(self: *Wasm, comp: *Compilation, prog_node: *std.Progress.Node) !...@@ -2274,7 +2274,7 @@ fn linkWithLLD(self: *Wasm, comp: *Compilation, prog_node: *std.Progress.Node) !
2274 // We are about to obtain this lock, so here we give other processes a chance first.2274 // We are about to obtain this lock, so here we give other processes a chance first.
2275 self.base.releaseLock();2275 self.base.releaseLock();
22762276
2277 comptime assert(Compilation.link_hash_implementation_version == 3);2277 comptime assert(Compilation.link_hash_implementation_version == 4);
22782278
2279 for (self.base.options.objects) |obj| {2279 for (self.base.options.objects) |obj| {
2280 _ = try man.addFile(obj.path, null);2280 _ = try man.addFile(obj.path, null);
src/main.zig+12
...@@ -447,6 +447,7 @@ const usage_build_generic =...@@ -447,6 +447,7 @@ const usage_build_generic =
447 \\ -F[dir] (Darwin) add search path for frameworks447 \\ -F[dir] (Darwin) add search path for frameworks
448 \\ -install_name=[value] (Darwin) add dylib's install name448 \\ -install_name=[value] (Darwin) add dylib's install name
449 \\ --entitlements [path] (Darwin) add path to entitlements file for embedding in code signature449 \\ --entitlements [path] (Darwin) add path to entitlements file for embedding in code signature
450 \\ -pagezero_size [value] (Darwin) size of the __PAGEZERO segment
450 \\ --import-memory (WebAssembly) import memory from the environment451 \\ --import-memory (WebAssembly) import memory from the environment
451 \\ --import-table (WebAssembly) import function table from the host environment452 \\ --import-table (WebAssembly) import function table from the host environment
452 \\ --export-table (WebAssembly) export function table to the host environment453 \\ --export-table (WebAssembly) export function table to the host environment
...@@ -694,6 +695,7 @@ fn buildOutputType(...@@ -694,6 +695,7 @@ fn buildOutputType(
694 var install_name: ?[]const u8 = null;695 var install_name: ?[]const u8 = null;
695 var hash_style: link.HashStyle = .both;696 var hash_style: link.HashStyle = .both;
696 var entitlements: ?[]const u8 = null;697 var entitlements: ?[]const u8 = null;
698 var pagezero_size: ?u64 = null;
697699
698 // e.g. -m3dnow or -mno-outline-atomics. They correspond to std.Target llvm cpu feature names.700 // e.g. -m3dnow or -mno-outline-atomics. They correspond to std.Target llvm cpu feature names.
699 // This array is populated by zig cc frontend and then has to be converted to zig-style701 // This array is populated by zig cc frontend and then has to be converted to zig-style
...@@ -1647,6 +1649,15 @@ fn buildOutputType(...@@ -1647,6 +1649,15 @@ fn buildOutputType(
1647 linker_optimization = std.fmt.parseUnsigned(u8, arg["-O".len..], 10) catch |err| {1649 linker_optimization = std.fmt.parseUnsigned(u8, arg["-O".len..], 10) catch |err| {
1648 fatal("unable to parse '{s}': {s}", .{ arg, @errorName(err) });1650 fatal("unable to parse '{s}': {s}", .{ arg, @errorName(err) });
1649 };1651 };
1652 } else if (mem.eql(u8, arg, "-pagezero_size")) {
1653 i += 1;
1654 if (i >= linker_args.items.len) {
1655 fatal("expected linker arg after '{s}'", .{arg});
1656 }
1657 const next_arg = linker_args.items[i];
1658 pagezero_size = std.fmt.parseUnsigned(u64, next_arg, 0) catch |err| {
1659 fatal("unable to parse '{s}': {s}", .{ arg, @errorName(err) });
1660 };
1650 } else if (mem.eql(u8, arg, "--gc-sections")) {1661 } else if (mem.eql(u8, arg, "--gc-sections")) {
1651 linker_gc_sections = true;1662 linker_gc_sections = true;
1652 } else if (mem.eql(u8, arg, "--no-gc-sections")) {1663 } else if (mem.eql(u8, arg, "--no-gc-sections")) {
...@@ -2763,6 +2774,7 @@ fn buildOutputType(...@@ -2763,6 +2774,7 @@ fn buildOutputType(
2763 .native_darwin_sdk = native_darwin_sdk,2774 .native_darwin_sdk = native_darwin_sdk,
2764 .install_name = install_name,2775 .install_name = install_name,
2765 .entitlements = entitlements,2776 .entitlements = entitlements,
2777 .pagezero_size = pagezero_size,
2766 }) catch |err| switch (err) {2778 }) catch |err| switch (err) {
2767 error.LibCUnavailable => {2779 error.LibCUnavailable => {
2768 const target = target_info.target;2780 const target = target_info.target;