Merge pull request #13964 from ziglang/issue-11737

Misc MachO linker improvements and link-tests refactor

Author: kubkon

CMakeLists.txt

@@ -585,10 +585,13 @@ set(ZIG_STAGE2_SOURCES
     "${CMAKE_SOURCE_DIR}/src/link/MachO/DwarfInfo.zig"
     "${CMAKE_SOURCE_DIR}/src/link/MachO/Dylib.zig"
     "${CMAKE_SOURCE_DIR}/src/link/MachO/Object.zig"
+    "${CMAKE_SOURCE_DIR}/src/link/MachO/Relocation.zig"
     "${CMAKE_SOURCE_DIR}/src/link/MachO/Trie.zig"
     "${CMAKE_SOURCE_DIR}/src/link/MachO/ZldAtom.zig"
     "${CMAKE_SOURCE_DIR}/src/link/MachO/bind.zig"
     "${CMAKE_SOURCE_DIR}/src/link/MachO/dead_strip.zig"
+    "${CMAKE_SOURCE_DIR}/src/link/MachO/fat.zig"
+    "${CMAKE_SOURCE_DIR}/src/link/MachO/load_commands.zig"
     "${CMAKE_SOURCE_DIR}/src/link/MachO/thunks.zig"
     "${CMAKE_SOURCE_DIR}/src/link/MachO/zld.zig"
     "${CMAKE_SOURCE_DIR}/src/link/Plan9.zig"

ci/aarch64-macos.sh

@@ -52,3 +52,19 @@ stage3-release/bin/zig build test docs \
 
 # Produce the experimental std lib documentation.
 stage3-release/bin/zig test ../lib/std/std.zig -femit-docs -fno-emit-bin --zig-lib-dir ../lib
+
+# Ensure that stage3 and stage4 are byte-for-byte identical.
+stage3-release/bin/zig build \
+  --prefix stage4-release \
+  -Denable-llvm \
+  -Dno-lib \
+  -Drelease \
+  -Dstrip \
+  -Dtarget=$TARGET \
+  -Duse-zig-libcxx \
+  -Dversion-string="$(stage3-release/bin/zig version)"
+
+# diff returns an error code if the files differ.
+echo "If the following command fails, it means nondeterminism has been"
+echo "introduced, making stage3 and stage4 no longer byte-for-byte identical."
+diff stage3-release/bin/zig stage4-release/bin/zig

ci/x86_64-macos.sh

@@ -60,3 +60,19 @@ stage3-release/bin/zig build test docs \
 
 # Produce the experimental std lib documentation.
 stage3-release/bin/zig test ../lib/std/std.zig -femit-docs -fno-emit-bin --zig-lib-dir ../lib
+
+# Ensure that stage3 and stage4 are byte-for-byte identical.
+stage3-release/bin/zig build \
+  --prefix stage4-release \
+  -Denable-llvm \
+  -Dno-lib \
+  -Drelease \
+  -Dstrip \
+  -Dtarget=$TARGET \
+  -Duse-zig-libcxx \
+  -Dversion-string="$(stage3-release/bin/zig version)"
+
+# diff returns an error code if the files differ.
+echo "If the following command fails, it means nondeterminism has been"
+echo "introduced, making stage3 and stage4 no longer byte-for-byte identical."
+diff stage3-release/bin/zig stage4-release/bin/zig

lib/std/build/CheckObjectStep.zig

@@ -571,6 +571,12 @@ const MachODumper = struct {
                 });
             },
 
+            .UUID => {
+                const uuid = lc.cast(macho.uuid_command).?;
+                try writer.writeByte('\n');
+                try writer.print("uuid {x}", .{std.fmt.fmtSliceHexLower(&uuid.uuid)});
+            },
+
             else => {},
         }
     }

lib/std/macho.zig

@@ -58,10 +58,10 @@ pub const uuid_command = extern struct {
     cmd: LC = .UUID,
 
     /// sizeof(struct uuid_command)
-    cmdsize: u32,
+    cmdsize: u32 = @sizeOf(uuid_command),
 
     /// the 128-bit uuid
-    uuid: [16]u8,
+    uuid: [16]u8 = undefined,
 };
 
 /// The version_min_command contains the min OS version on which this
@@ -71,7 +71,7 @@ pub const version_min_command = extern struct {
     cmd: LC,
 
     /// sizeof(struct version_min_command)
-    cmdsize: u32,
+    cmdsize: u32 = @sizeOf(version_min_command),
 
     /// X.Y.Z is encoded in nibbles xxxx.yy.zz
     version: u32,
@@ -87,7 +87,7 @@ pub const source_version_command = extern struct {
     cmd: LC = .SOURCE_VERSION,
 
     /// sizeof(source_version_command)
-    cmdsize: u32,
+    cmdsize: u32 = @sizeOf(source_version_command),
 
     /// A.B.C.D.E packed as a24.b10.c10.d10.e10
     version: u64,
@@ -155,13 +155,13 @@ pub const entry_point_command = extern struct {
     cmd: LC = .MAIN,
 
     /// sizeof(struct entry_point_command)
-    cmdsize: u32,
+    cmdsize: u32 = @sizeOf(entry_point_command),
 
     /// file (__TEXT) offset of main()
-    entryoff: u64,
+    entryoff: u64 = 0,
 
     /// if not zero, initial stack size
-    stacksize: u64,
+    stacksize: u64 = 0,
 };
 
 /// The symtab_command contains the offsets and sizes of the link-edit 4.3BSD
@@ -172,19 +172,19 @@ pub const symtab_command = extern struct {
     cmd: LC = .SYMTAB,
 
     /// sizeof(struct symtab_command)
-    cmdsize: u32,
+    cmdsize: u32 = @sizeOf(symtab_command),
 
     /// symbol table offset
-    symoff: u32,
+    symoff: u32 = 0,
 
     /// number of symbol table entries
-    nsyms: u32,
+    nsyms: u32 = 0,
 
     /// string table offset
-    stroff: u32,
+    stroff: u32 = 0,
 
     /// string table size in bytes
-    strsize: u32,
+    strsize: u32 = 0,
 };
 
 /// This is the second set of the symbolic information which is used to support
@@ -230,7 +230,7 @@ pub const dysymtab_command = extern struct {
     cmd: LC = .DYSYMTAB,
 
     /// sizeof(struct dysymtab_command)
-    cmdsize: u32,
+    cmdsize: u32 = @sizeOf(dysymtab_command),
 
     // The symbols indicated by symoff and nsyms of the LC_SYMTAB load command
     // are grouped into the following three groups:
@@ -247,22 +247,22 @@ pub const dysymtab_command = extern struct {
     // table when this is a dynamically linked shared library file).
 
     /// index of local symbols
-    ilocalsym: u32,
+    ilocalsym: u32 = 0,
 
     /// number of local symbols
-    nlocalsym: u32,
+    nlocalsym: u32 = 0,
 
     /// index to externally defined symbols
-    iextdefsym: u32,
+    iextdefsym: u32 = 0,
 
     /// number of externally defined symbols
-    nextdefsym: u32,
+    nextdefsym: u32 = 0,
 
     /// index to undefined symbols
-    iundefsym: u32,
+    iundefsym: u32 = 0,
 
     /// number of undefined symbols
-    nundefsym: u32,
+    nundefsym: u32 = 0,
 
     // For the for the dynamic binding process to find which module a symbol
     // is defined in the table of contents is used (analogous to the ranlib
@@ -272,10 +272,10 @@ pub const dysymtab_command = extern struct {
     // symbols are sorted by name and is use as the table of contents.
 
     /// file offset to table of contents
-    tocoff: u32,
+    tocoff: u32 = 0,
 
     /// number of entries in table of contents
-    ntoc: u32,
+    ntoc: u32 = 0,
 
     // To support dynamic binding of "modules" (whole object files) the symbol
     // table must reflect the modules that the file was created from.  This is
@@ -286,10 +286,10 @@ pub const dysymtab_command = extern struct {
     // contains one module so everything in the file belongs to the module.
 
     /// file offset to module table
-    modtaboff: u32,
+    modtaboff: u32 = 0,
 
     /// number of module table entries
-    nmodtab: u32,
+    nmodtab: u32 = 0,
 
     // To support dynamic module binding the module structure for each module
     // indicates the external references (defined and undefined) each module
@@ -300,10 +300,10 @@ pub const dysymtab_command = extern struct {
     // undefined external symbols indicates the external references.
 
     /// offset to referenced symbol table
-    extrefsymoff: u32,
+    extrefsymoff: u32 = 0,
 
     /// number of referenced symbol table entries
-    nextrefsyms: u32,
+    nextrefsyms: u32 = 0,
 
     // The sections that contain "symbol pointers" and "routine stubs" have
     // indexes and (implied counts based on the size of the section and fixed
@@ -315,10 +315,10 @@ pub const dysymtab_command = extern struct {
     // The indirect symbol table is ordered to match the entries in the section.
 
     /// file offset to the indirect symbol table
-    indirectsymoff: u32,
+    indirectsymoff: u32 = 0,
 
     /// number of indirect symbol table entries
-    nindirectsyms: u32,
+    nindirectsyms: u32 = 0,
 
     // To support relocating an individual module in a library file quickly the
     // external relocation entries for each module in the library need to be
@@ -347,20 +347,20 @@ pub const dysymtab_command = extern struct {
     // remaining relocation entries must be local).
 
     /// offset to external relocation entries
-    extreloff: u32,
+    extreloff: u32 = 0,
 
     /// number of external relocation entries
-    nextrel: u32,
+    nextrel: u32 = 0,
 
     // All the local relocation entries are grouped together (they are not
     // grouped by their module since they are only used if the object is moved
     // from it staticly link edited address).
 
     /// offset to local relocation entries
-    locreloff: u32,
+    locreloff: u32 = 0,
 
     /// number of local relocation entries
-    nlocrel: u32,
+    nlocrel: u32 = 0,
 };
 
 /// The linkedit_data_command contains the offsets and sizes of a blob
@@ -370,13 +370,13 @@ pub const linkedit_data_command = extern struct {
     cmd: LC,
 
     /// sizeof(struct linkedit_data_command)
-    cmdsize: u32,
+    cmdsize: u32 = @sizeOf(linkedit_data_command),
 
     /// file offset of data in __LINKEDIT segment
-    dataoff: u32,
+    dataoff: u32 = 0,
 
     /// file size of data in __LINKEDIT segment
-    datasize: u32,
+    datasize: u32 = 0,
 };
 
 /// The dyld_info_command contains the file offsets and sizes of
@@ -387,10 +387,10 @@ pub const linkedit_data_command = extern struct {
 /// to interpret it.
 pub const dyld_info_command = extern struct {
     /// LC_DYLD_INFO or LC_DYLD_INFO_ONLY
-    cmd: LC,
+    cmd: LC = .DYLD_INFO_ONLY,
 
     /// sizeof(struct dyld_info_command)
-    cmdsize: u32,
+    cmdsize: u32 = @sizeOf(dyld_info_command),
 
     // Dyld rebases an image whenever dyld loads it at an address different
     // from its preferred address.  The rebase information is a stream
@@ -403,10 +403,10 @@ pub const dyld_info_command = extern struct {
     // bytes.
 
     /// file offset to rebase info
-    rebase_off: u32,
+    rebase_off: u32 = 0,
 
     /// size of rebase info
-    rebase_size: u32,
+    rebase_size: u32 = 0,
 
     // Dyld binds an image during the loading process, if the image
     // requires any pointers to be initialized to symbols in other images.
@@ -420,10 +420,10 @@ pub const dyld_info_command = extern struct {
     // encoded in a few bytes.
 
     /// file offset to binding info
-    bind_off: u32,
+    bind_off: u32 = 0,
 
     /// size of binding info
-    bind_size: u32,
+    bind_size: u32 = 0,
 
     // Some C++ programs require dyld to unique symbols so that all
     // images in the process use the same copy of some code/data.
@@ -440,10 +440,10 @@ pub const dyld_info_command = extern struct {
     // and the call to operator new is then rebound.
 
     /// file offset to weak binding info
-    weak_bind_off: u32,
+    weak_bind_off: u32 = 0,
 
     /// size of weak binding info
-    weak_bind_size: u32,
+    weak_bind_size: u32 = 0,
 
     // Some uses of external symbols do not need to be bound immediately.
     // Instead they can be lazily bound on first use.  The lazy_bind
@@ -457,10 +457,10 @@ pub const dyld_info_command = extern struct {
     // to bind.
 
     /// file offset to lazy binding info
-    lazy_bind_off: u32,
+    lazy_bind_off: u32 = 0,
 
     /// size of lazy binding info
-    lazy_bind_size: u32,
+    lazy_bind_size: u32 = 0,
 
     // The symbols exported by a dylib are encoded in a trie.  This
     // is a compact representation that factors out common prefixes.
@@ -494,10 +494,10 @@ pub const dyld_info_command = extern struct {
     // edge points to.
 
     /// file offset to lazy binding info
-    export_off: u32,
+    export_off: u32 = 0,
 
     /// size of lazy binding info
-    export_size: u32,
+    export_size: u32 = 0,
 };
 
 /// A program that uses a dynamic linker contains a dylinker_command to identify