[llvm-objdump] Start on -chained_fixups for llvm-otool

[thakis]

Summary

And --chained-fixups for llvm-objdump.

For now, this only prints the dyld_chained_fixups_header and adds
plumbing for the flag. This will be expanded in future commits.

When Apple's effort to upstream their chained fixups code continues,
we'll replace this code with the then-upstreamed code. But we need
something in the meantime for testing ld64.lld's chained fixups
code.

Update chained-fixups.yaml with a file that actually contains
the chained fixup data (LinkEditData doesn't encode it yet,
so use __LINKEDIT via --raw-segment=data).

[thakis]

llvm/test/tools/llvm-objdump/MachO/chained-fixups.yaml

21

The test currently doesn't work, because the yaml file here (added in D113733, where I left a question about it) contains invalid data. I'll fix up the yaml file in a bit. Currently, we get:

out/gn/bin/llvm-objdump: error: '.../obj/llvm/test/tools/llvm-objdump/MachO/Output/chained-fixups.yaml.tmp': truncated or malformed object (bad chained fixups: unknown imports format: 0)

[thakis]

update test

[thakis]

ok, good to go

[jhenderson]

I'm not going to review this as it's Mach-O stuff, which is outside my realms of expertise, but please don't forget to update the llvm-objdump and llvm-otool CommandGuides located under llvm/docs/CommandGuide.

[thakis]

update rst files

[thakis]

In D131890#3723094, @jhenderson wrote:

I'm not going to review this as it's Mach-O stuff, which is outside my realms of expertise, but please don't forget to update the llvm-objdump and llvm-otool CommandGuides located under llvm/docs/CommandGuide.

Done, thanks!

[stefanp]

@thakis

It looks like this patch is causing one of the Big Endian bots to fail on Power PC:
https://lab.llvm.org/buildbot/#/builders/231/builds/1440

The failure is the test tools/llvm-objdump/MachO/chained-fixups.yaml.

[thakis]

In D131890#3724098, @stefanp wrote:

@thakis

It looks like this patch is causing one of the Big Endian bots to fail on Power PC:
https://lab.llvm.org/buildbot/#/builders/231/builds/1440

The failure is the test tools/llvm-objdump/MachO/chained-fixups.yaml.

Could you paste the whole output of bin/llvm-otool -chained_fixups /home/buildbots/ppc64be-clang-test-suite/clang-ppc64be-test-suite/build/test/tools/llvm-objdump/MachO/Output/chained-fixups.yaml.tmp on that bot?

[thakis]

I'm guessing the problem is that MachOObjectFile.cpp swaps load commands and assumes native byte endianness – but the yaml test here uses __LINKEDIT which always contains little-endian data.

Possible fixes:

1. Force the yaml2obj output to be little endian somehow (I don't see a flag for this, though – am I not looking closely enough?)
2. Skip the test on big endian machines (do we have a lit feature for this?)

[thakis]

Maybe 8403cd5b00b916c1172fef2d867dcc37e159c7ec will help.

[thakis]

In D131890#3724321, @thakis wrote:

Maybe 8403cd5b00b916c1172fef2d867dcc37e159c7ec will help.

Looks like it did help: https://lab.llvm.org/buildbot/#/builders/231/builds/1454

[stefanp]

In D131890#3724463, @thakis wrote:

In D131890#3724321, @thakis wrote:

Maybe 8403cd5b00b916c1172fef2d867dcc37e159c7ec will help.

Looks like it did help: https://lab.llvm.org/buildbot/#/builders/231/builds/1454

Thank you for fix this!

llvm/docs/CommandGuide/llvm-objdump.rst

 .. option:: --data-in-code
 
   Display the data in code table.
 
 .. option:: --dis-symname=<name>
 
   Disassemble just the specified symbol's instructions.
 
+.. option:: --chained-fixups
+
+  Print chained fixup information.
+
 .. option:: --dyld_info
 
   Print bind and rebase information used by dyld to resolve external
   references in a final linked binary.
 
 .. option:: --dylibs-used
 
   Display the shared libraries used for linked files.

llvm/docs/CommandGuide/llvm-otool.rst

 
 OPTIONS
 -------
 
 .. option:: -arch <value>
 
  Select slice of universal Mach-O file.
 
+.. option:: -chained_fixups
+
+ Print chained fixup information.
+
 .. option:: -C
 
  Print linker optimization hints.
 
 .. option:: -D
 
  Print shared library id.
 

llvm/include/llvm/BinaryFormat/MachO.h

 struct nlist_64 {
   uint32_t n_strx;
   uint8_t n_type;
   uint8_t n_sect;
   uint16_t n_desc;
   uint64_t n_value;
 };
 
+// Values for dyld_chained_fixups_header::imports_format.
+enum {
+  DYLD_CHAINED_IMPORT = 1,
+  DYLD_CHAINED_IMPORT_ADDEND = 2,
+  DYLD_CHAINED_IMPORT_ADDEND64 = 3,
+};
+
+// Values for dyld_chained_fixups_header::symbols_format.
+enum {
+  DYLD_CHAINED_SYMBOL_UNCOMPRESSED = 0,
+  DYLD_CHAINED_SYMBOL_ZLIB = 1,
+};
+
 /// Structs for dyld chained fixups.
 /// dyld_chained_fixups_header is the data pointed to by LC_DYLD_CHAINED_FIXUPS
 /// load command.
 struct dyld_chained_fixups_header {
   uint32_t fixups_version; ///< 0
   uint32_t starts_offset;  ///< Offset of dyld_chained_starts_in_image.
   uint32_t imports_offset; ///< Offset of imports table in chain_data.
   uint32_t symbols_offset; ///< Offset of symbol strings in chain_data.

llvm/test/tools/llvm-objdump/MachO/chained-fixups.yaml

 # RUN: yaml2obj %s -o %t
 # RUN: llvm-objdump -p %t | FileCheck %s
 # RUN: llvm-otool -l %t | FileCheck %s
-#
+
 # CHECK: LC_DYLD_CHAINED_FIXUPS
 # CHECK: LC_DYLD_EXPORTS_TRIE
 
+# RUN: llvm-objdump --macho --chained-fixups %t | \
+# RUN:     FileCheck --check-prefix=DETAILS -DNAME=%t %s
+# RUN: llvm-otool -chained_fixups %t | \
+# RUN:     FileCheck --check-prefix=DETAILS -DNAME=%t %s
+
+# DETAILS:      [[NAME]]:
+# DETAILS-NEXT: chained fixups header (LC_DYLD_CHAINED_FIXUPS)
+# DETAILS-NEXT:   fixups_version = 0
+# DETAILS-NEXT:   starts_offset  = 32
+# DETAILS-NEXT:   imports_offset = 44
+# DETAILS-NEXT:   symbols_offset = 44
+# DETAILS-NEXT:   imports_count  = 0
+# DETAILS-NEXT:   imports_format = 1 (DYLD_CHAINED_IMPORT)
+# DETAILS-NEXT:   symbols_format = 0
+
+## This yaml is from a dylib produced by ld64
+##   echo ".global _foo\n_foo" > dylib.s
+##   clang -target=x86_64-apple-macos12 -dynamiclib -isysroot Inputs/MacOSX.sdk dylib.s -o libdylib.dylib
+##   obj2yaml --raw-segment=data libdylib.dylib
 --- !mach-o
 FileHeader:
   magic:           0xFEEDFACF
-  cputype:         0x100000C
-  cpusubtype:      0x0
-  filetype:        0x2
-  ncmds:           16
-  sizeofcmds:      744
-  flags:           0x200085
+  cputype:         0x1000007
+  cpusubtype:      0x3
+  filetype:        0x6
+  ncmds:           13
+  sizeofcmds:      568
+  flags:           0x100085
   reserved:        0x0
 LoadCommands:
   - cmd:             LC_SEGMENT_64
-    cmdsize:         72
-    segname:         __PAGEZERO
-    vmaddr:          0
-    vmsize:          4294967296
-    fileoff:         0
-    filesize:        0
-    maxprot:         0
-    initprot:        0
-    nsects:          0
-    flags:           0
-  - cmd:             LC_SEGMENT_64
-    cmdsize:         232
+    cmdsize:         152
     segname:         __TEXT
-    vmaddr:          4294967296
+    vmaddr:          0
     vmsize:          16384
     fileoff:         0
     filesize:        16384
     maxprot:         5
     initprot:        5
-    nsects:          2
+    nsects:          1
     flags:           0
     Sections:
       - sectname:        __text
         segname:         __TEXT
-        addr:            0x100003F98
-        size:            24
-        offset:          0x3F98
-        align:           2
+        addr:            0x4000
+        size:            0
+        offset:          0x4000
+        align:           0
         reloff:          0x0
         nreloc:          0
         flags:           0x80000400
         reserved1:       0x0
         reserved2:       0x0
         reserved3:       0x0
-        content:         C0035FD6FF4300D100008052FF0F00B9FF430091C0035FD6
-      - sectname:        __unwind_info
-        segname:         __TEXT
-        addr:            0x100003FB0
-        size:            80
-        offset:          0x3FB0
-        align:           2
-        reloff:          0x0
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-        flags:           0x0
-        reserved1:       0x0
-        reserved2:       0x0
-        reserved3:       0x0
-        content:         010000001C000000000000001C000000000000001C00000002000000983F00003400000034000000B13F00000000000034000000030000000C0002001400020000000001040000000010000200000002
+        content:         ''
   - cmd:             LC_SEGMENT_64
     cmdsize:         72
     segname:         __LINKEDIT
-    vmaddr:          4294983680
+    vmaddr:          16384
     vmsize:          16384
     fileoff:         16384
-    filesize:        753
+    filesize:        96
     maxprot:         1
     initprot:        1
     nsects:          0
     flags:           0
+  - cmd:             LC_ID_DYLIB
+    cmdsize:         48
+    dylib:
+      name:            24
+      timestamp:       1
+      current_version: 0
+      compatibility_version: 0
+    Content:         libdylib.dylib
+    ZeroPadBytes:    3
   - cmd:             LC_DYLD_CHAINED_FIXUPS
     cmdsize:         16
     dataoff:         16384
-    datasize:        56
+    datasize:        48
   - cmd:             LC_DYLD_EXPORTS_TRIE
     cmdsize:         16
-    dataoff:         16440
-    datasize:        56
+    dataoff:         16432
+    datasize:        16
   - cmd:             LC_SYMTAB
     cmdsize:         24
-    symoff:          16504
-    nsyms:           15
-    stroff:          16744
-    strsize:         120
+    symoff:          16456
+    nsyms:           1
+    stroff:          16472
+    strsize:         8
   - cmd:             LC_DYSYMTAB
     cmdsize:         80
     ilocalsym:       0
-    nlocalsym:       12
-    iextdefsym:      12
-    nextdefsym:      3
-    iundefsym:       15
+    nlocalsym:       0
+    iextdefsym:      0
+    nextdefsym:      1
+    iundefsym:       1
     nundefsym:       0
     tocoff:          0
     ntoc:            0
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     nmodtab:         0
     extrefsymoff:    0
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     nindirectsyms:   0
     extreloff:       0
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     locreloff:       0
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-  - cmd:             LC_LOAD_DYLINKER
-    cmdsize:         32
-    name:            12
-    Content:         '/usr/lib/dyld'
-    ZeroPadBytes:    7
   - cmd:             LC_UUID
     cmdsize:         24
-    uuid:            F445529E-643C-3A38-8F59-AB64566BCAFF
+    uuid:            52409B91-DF59-346A-A63F-D4E6FFDC3E04
   - cmd:             LC_BUILD_VERSION
     cmdsize:         32
     platform:        1
     minos:           786432
-    sdk:             786432
+    sdk:             851968
     ntools:          1
     Tools:
       - tool:            3
-        version:         46596096
+        version:         53674242
   - cmd:             LC_SOURCE_VERSION
     cmdsize:         16
     version:         0
-  - cmd:             LC_MAIN
-    cmdsize:         24
-    entryoff:        16284
-    stacksize:       0
   - cmd:             LC_LOAD_DYLIB
     cmdsize:         56
     dylib:
       name:            24
       timestamp:       2
-      current_version: 85917696
+      current_version: 65793
       compatibility_version: 65536
-    Content:         '/usr/lib/libSystem.B.dylib'
-    ZeroPadBytes:    6
+    Content:         '/usr/lib/libSystem.dylib'
+    ZeroPadBytes:    8
   - cmd:             LC_FUNCTION_STARTS
     cmdsize:         16
-    dataoff:         16496
+    dataoff:         16448
     datasize:        8
   - cmd:             LC_DATA_IN_CODE
     cmdsize:         16
-    dataoff:         16504
+    dataoff:         16456
     datasize:        0
-  - cmd:             LC_CODE_SIGNATURE
-    cmdsize:         16
-    dataoff:         16864
-    datasize:        273
-LinkEditData:
-  NameList:
-    - n_strx:          33
-      n_type:          0x64
-      n_sect:          0
-      n_desc:          0
-      n_value:         0
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-      n_type:          0xF
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-  StringTable:
-    - ' '
-    - __mh_execute_header
-    - _foo
-    - _main
-    - '/tmp/'
-    - main.c
-    - '/var/folders/gj/wf3swl0x215b2sq1qy84kzkm0000gn/T/main-e32fe7.o'
-    - _foo
-    - _main
+__LINKEDIT:      00000000200000002C0000002C000000000000000100000000000000000000000200000000000000000000000000000000015F666F6F000804008080010000000000000000000000020000000F010000004000000000000020005F666F6F0000
 ...

llvm/tools/llvm-objdump/MachODump.h

 namespace objdump {
 
 void parseMachOOptions(const llvm::opt::InputArgList &InputArgs);
 
 // MachO specific options
 extern bool Bind;
 extern bool DataInCode;
 extern std::string DisSymName;
+extern bool ChainedFixups;
 extern bool DyldInfo;
 extern bool DylibId;
 extern bool DylibsUsed;
 extern bool ExportsTrie;
 extern bool FirstPrivateHeader;
 extern bool FullLeadingAddr;
 extern bool FunctionStarts;
 extern bool IndirectSymbols;

llvm/tools/llvm-objdump/MachODump.cpp

 bool objdump::LeadingHeaders;
 bool objdump::UniversalHeaders;
 static bool ArchiveMemberOffsets;
 bool objdump::IndirectSymbols;
 bool objdump::DataInCode;
 bool objdump::FunctionStarts;
 bool objdump::LinkOptHints;
 bool objdump::InfoPlist;
+bool objdump::ChainedFixups;
 bool objdump::DyldInfo;
 bool objdump::DylibsUsed;
 bool objdump::DylibId;
 bool objdump::Verbose;
 bool objdump::ObjcMetaData;
 std::string objdump::DisSymName;
 bool objdump::SymbolicOperands;
 static std::vector<std::string> ArchFlags;
void objdump::parseMachOOptions(const llvm::opt::InputArgList &InputArgs) {
   LeadingHeaders = !InputArgs.hasArg(OBJDUMP_no_leading_headers);
   UniversalHeaders = InputArgs.hasArg(OBJDUMP_universal_headers);
   ArchiveMemberOffsets = InputArgs.hasArg(OBJDUMP_archive_member_offsets);
   IndirectSymbols = InputArgs.hasArg(OBJDUMP_indirect_symbols);
   DataInCode = InputArgs.hasArg(OBJDUMP_data_in_code);
   FunctionStarts = InputArgs.hasArg(OBJDUMP_function_starts);
   LinkOptHints = InputArgs.hasArg(OBJDUMP_link_opt_hints);
   InfoPlist = InputArgs.hasArg(OBJDUMP_info_plist);
+  ChainedFixups = InputArgs.hasArg(OBJDUMP_chained_fixups);
   DyldInfo = InputArgs.hasArg(OBJDUMP_dyld_info);
   DylibsUsed = InputArgs.hasArg(OBJDUMP_dylibs_used);
   DylibId = InputArgs.hasArg(OBJDUMP_dylib_id);
   Verbose = !InputArgs.hasArg(OBJDUMP_non_verbose);
   ObjcMetaData = InputArgs.hasArg(OBJDUMP_objc_meta_data);
   DisSymName = InputArgs.getLastArgValue(OBJDUMP_dis_symname).str();
   SymbolicOperands = !InputArgs.hasArg(OBJDUMP_no_symbolic_operands);
   ArchFlags = InputArgs.getAllArgValues(OBJDUMP_arch_EQ);
static void printMachOChainedFixups(object::MachOObjectFile *Obj) {
   Error Err = Error::success();
   for (const object::MachOChainedFixupEntry &Entry : Obj->fixupTable(Err)) {
     (void)Entry;
   }
   if (Err)
     reportError(std::move(Err), Obj->getFileName());
 }
 
+static void
+PrintChainedFixupsHeader(const MachO::dyld_chained_fixups_header &H) {
+  outs() << "chained fixups header (LC_DYLD_CHAINED_FIXUPS)\n";
+  outs() << "  fixups_version = " << H.fixups_version << '\n';
+  outs() << "  starts_offset  = " << H.starts_offset << '\n';
+  outs() << "  imports_offset = " << H.imports_offset << '\n';
+  outs() << "  symbols_offset = " << H.symbols_offset << '\n';
+  outs() << "  imports_count  = " << H.imports_count << '\n';
+
+  outs() << "  imports_format = " << H.imports_format;
+  switch (H.imports_format) {
+  case llvm::MachO::DYLD_CHAINED_IMPORT:
+    outs() << " (DYLD_CHAINED_IMPORT)";
+    break;
+  case llvm::MachO::DYLD_CHAINED_IMPORT_ADDEND:
+    outs() << " (DYLD_CHAINED_IMPORT_ADDEND)";
+    break;
+  case llvm::MachO::DYLD_CHAINED_IMPORT_ADDEND64:
+    outs() << " (DYLD_CHAINED_IMPORT_ADDEND64)";
+    break;
+  }
+  outs() << '\n';
+
+  outs() << "  symbols_format = " << H.symbols_format;
+  if (H.symbols_format == llvm::MachO::DYLD_CHAINED_SYMBOL_ZLIB)
+    outs() << " (zlib compressed)";
+  outs() << '\n';
+}
+
+static void PrintChainedFixups(MachOObjectFile *O) {
+  // MachOObjectFile::getChainedFixupsHeader() reads LC_DYLD_CHAINED_FIXUPS.
+  // FIXME: Support chained fixups in __TEXT,__chain_starts section too.
+  auto ChainedFixupHeader =
+      unwrapOrError(O->getChainedFixupsHeader(), O->getFileName());
+  if (!ChainedFixupHeader)
+    return;
+
+  PrintChainedFixupsHeader(*ChainedFixupHeader);
+
+  // FIXME: Print more things.
+}
+
 static void PrintDyldInfo(MachOObjectFile *O) {
   outs() << "dyld information:" << '\n';
   printMachOChainedFixups(O);
 }
 
 static void PrintDylibs(MachOObjectFile *O, bool JustId) {
   unsigned Index = 0;
   for (const auto &Load : O->load_commands()) {

 static void ProcessMachO(StringRef Name, MachOObjectFile *MachOOF,
                          StringRef ArchiveMemberName = StringRef(),
                          StringRef ArchitectureName = StringRef()) {
   // If we are doing some processing here on the Mach-O file print the header
   // info.  And don't print it otherwise like in the case of printing the
   // UniversalHeaders or ArchiveHeaders.
   if (Disassemble || Relocations || PrivateHeaders || ExportsTrie || Rebase ||
       Bind || SymbolTable || LazyBind || WeakBind || IndirectSymbols ||
-      DataInCode || FunctionStarts || LinkOptHints || DyldInfo || DylibsUsed ||
-      DylibId || Rpaths || ObjcMetaData || (!FilterSections.empty())) {
+      DataInCode || FunctionStarts || LinkOptHints || ChainedFixups ||
+      DyldInfo || DylibsUsed || DylibId || Rpaths || ObjcMetaData ||
+      (!FilterSections.empty())) {
     if (LeadingHeaders) {
       outs() << Name;
       if (!ArchiveMemberName.empty())
         outs() << '(' << ArchiveMemberName << ')';
       if (!ArchitectureName.empty())
         outs() << " (architecture " << ArchitectureName << ")";
       outs() << ":\n";
     }
static void ProcessMachO(StringRef Name, MachOObjectFile *MachOOF,
   if (SectionHeaders)
     printSectionHeaders(*MachOOF);
   if (SectionContents)
     printSectionContents(MachOOF);
   if (!FilterSections.empty())
     DumpSectionContents(FileName, MachOOF, Verbose);
   if (InfoPlist)
     DumpInfoPlistSectionContents(FileName, MachOOF);
+  if (ChainedFixups)
+    PrintChainedFixups(MachOOF);
   if (DyldInfo)
     PrintDyldInfo(MachOOF);
   if (DylibsUsed)
     PrintDylibs(MachOOF, false);
   if (DylibId)
     PrintDylibs(MachOOF, true);
   if (SymbolTable)
     printSymbolTable(*MachOOF, ArchiveName, ArchitectureName);

llvm/tools/llvm-objdump/ObjdumpOpts.td

HelpText<"Print the linker optimization hints for "
            "Mach-O objects (requires --macho)">,
   Group<grp_mach_o>;
 
 def info_plist : Flag<["--"], "info-plist">,
   HelpText<"Print the info plist section as strings for "
            "Mach-O objects (requires --macho)">,
   Group<grp_mach_o>;
 
+def chained_fixups : Flag<["--"], "chained-fixups">,
+  HelpText<"Print chained fixup information (requires --macho)">,
+  Group<grp_mach_o>;
+
 def dyld_info : Flag<["--"], "dyld_info">,
-      HelpText<"Print bind and rebase information used by dyld to resolve "
-               "external references in a final linked binary "
-               "(requires --macho)">,
-      Group<grp_mach_o>;
 
 def dylibs_used : Flag<["--"], "dylibs-used">,
   HelpText<"Print the shared libraries used for linked "
            "Mach-O files (requires --macho)">,
   Group<grp_mach_o>;
 
 def dylib_id : Flag<["--"], "dylib-id">,
   HelpText<"Print the shared library's id for the "

llvm/tools/llvm-objdump/OtoolOpts.td

 def version : Flag<["--"], "version">, HelpText<"print version">;
 def v : Flag<["-"], "v">,
   HelpText<"verbose output / disassemble when printing text sections">;
 def V : Flag<["-"], "V">,
   HelpText<"symbolize disassembled operands (implies -v)">;
 def x : Flag<["-"], "x">, HelpText<"print all text sections">;
 def X : Flag<["-"], "X">, HelpText<"omit leading addresses or headers">;
 
+def chained_fixups : Flag<["-"], "chained_fixups">,
+  HelpText<"print chained fixup information">;
+
 // Not (yet?) implemented:
 // def a : Flag<["-"], "a">, HelpText<"print archive header">;
 // -c print argument strings of a core file
 // -m don't use archive(member) syntax
 // -dyld_info
 // -dyld_opcodes
-// -chained_fixups
 // -addr_slide=arg
 // -function_offsets
 
 // Obsolete and unsupported:
 def grp_obsolete : OptionGroup<"kind">,
   HelpText<"Obsolete and unsupported flags">;
 
 def : Flag<["-"], "B">, Flags<[HelpHidden]>, Group<grp_obsolete>,

llvm/tools/llvm-objdump/llvm-objdump.cpp

if (InputArgs.hasArg(OTOOL_t))
     FilterSections.push_back("__TEXT,__text");
   Verbose = InputArgs.hasArg(OTOOL_v) || InputArgs.hasArg(OTOOL_V) ||
             InputArgs.hasArg(OTOOL_o);
   SymbolicOperands = InputArgs.hasArg(OTOOL_V);
   if (InputArgs.hasArg(OTOOL_x))
     FilterSections.push_back(",__text");
   LeadingAddr = LeadingHeaders = !InputArgs.hasArg(OTOOL_X);
 
+  ChainedFixups = InputArgs.hasArg(OTOOL_chained_fixups);
+
   InputFilenames = InputArgs.getAllArgValues(OTOOL_INPUT);
   if (InputFilenames.empty())
     reportCmdLineError("no input file");
 
   for (const Arg *A : InputArgs) {
     const Option &O = A->getOption();
     if (O.getGroup().isValid() && O.getGroup().getID() == OTOOL_grp_obsolete) {
       reportCmdLineWarning(O.getPrefixedName() +
int main(int argc, char **argv) {
   if (DisassembleAll || PrintSource || PrintLines ||
       !DisassembleSymbols.empty())
     Disassemble = true;
 
   if (!ArchiveHeaders && !Disassemble && DwarfDumpType == DIDT_Null &&
       !DynamicRelocations && !FileHeaders && !PrivateHeaders && !RawClangAST &&
       !Relocations && !SectionHeaders && !SectionContents && !SymbolTable &&
       !DynamicSymbolTable && !UnwindInfo && !FaultMapSection && !Offloading &&
-      !(MachOOpt && (Bind || DataInCode || DyldInfo || DylibId || DylibsUsed ||
-                     ExportsTrie || FirstPrivateHeader || FunctionStarts ||
-                     IndirectSymbols || InfoPlist || LazyBind || LinkOptHints ||
-                     ObjcMetaData || Rebase || Rpaths || UniversalHeaders ||
-                     WeakBind || !FilterSections.empty()))) {
+      !(MachOOpt &&
+        (Bind || DataInCode || ChainedFixups || DyldInfo || DylibId ||
+         DylibsUsed || ExportsTrie || FirstPrivateHeader || FunctionStarts ||
+         ObjcMetaData || Rebase || Rpaths || UniversalHeaders || WeakBind ||
+         !FilterSections.empty()))) {
     T->printHelp(ToolName);
     return 2;
   }
 
   DisasmSymbolSet.insert(DisassembleSymbols.begin(), DisassembleSymbols.end());
 
   llvm::for_each(InputFilenames, dumpInput);
 
   warnOnNoMatchForSections();
 
   return EXIT_SUCCESS;
 }