Compilation hangs with Xcode 11.4 and Swift 5.2 when -O optimizations are enabled

noremac · March 30, 2020, 6:44pm

My company's project no longer successfully compiles with Xcode 11.4 and Swift 5.2 when -O level optimizations are enabled. The build process seems to hang infinitely on Code Generation for Swift source files for a particular file. Using -Osize instead of -O works and is the workaround we are currently employing.

Unfortunately, I've not (yet) been unable to reduce this to a small sample project that demonstrates the problem.

Using -Osize is absolutely an acceptable solution for now (and maybe even in the long term) but I'd still like to know what's going on here. It seems clear there is some sort of very reproducible bug that I'd like to report, but I'm not sure what my options are given that I've not been able to reproduce in a sample project.

What else could I do to gather information and debug locally?

Some things I've tried:

My assumption is that Code Generation for Swift source files is referring to the phase where the compiler is generating code for us, like default Equatable implementations or default member-wise initializer implementations for structs. I've attempted to reduce this work to zero by manually writing all the Equatable implementations all member-wise initializers in the problem file. This has not helped.
I've added -Xfrontend -debug-time-function-bodies to OTHER_SWIFT_FLAGS and successfully used the build time analyzer tool, but it didn't have much to report when optimizations are enabled.

Joe_Groff · March 30, 2020, 6:48pm

The problem is most likely in the optimizer. You can send the hung swiftc process a signal such as SIGABRT, which should cause it to print a crash message with a backtrace, hopefully indicating what optimizer pass is currently running and what function it's operating on. That may help you narrow down where the problem is occurring.

noremac · March 30, 2020, 9:05pm

I've done: kill -6 <pid> which did not seem to do anything. The process kept going. kill -9 <pid> did stop the process, but it did not have any useful information in Xcode or in Console that I saw outside of listing the invocation that had started the process, and that it was illegally terminated.

Maybe I've not properly done what you suggested? Thanks for the help!

Joe_Groff · March 30, 2020, 11:22pm

If the process isn't responding to signals, then you might try running sample on it to see if you can get a backtrace from it that way.

noremac · April 6, 2020, 8:40pm

Spin dump here:

Sampling process 54572 for 1 second with 1 millisecond of run time between samples
Sampling completed, processing symbols...
Analysis of sampling swift (pid 54572) every 1 millisecond
Process:         swift [54572]
Path:            /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/swift
Load Address:    0x10385b000
Identifier:      swift
Version:         1103.0.32.1
Code Type:       X86-64
Parent Process:  swift [54476]

Date/Time:       2020-04-06 16:37:01.901 -0400
Launch Time:     2020-04-06 16:35:24.784 -0400
OS Version:      Mac OS X 10.15.4 (19E266)
Report Version:  7
Analysis Tool:   /usr/bin/sample

Physical footprint:         212.3M
Physical footprint (peak):  212.3M
----

Call graph:
    928 Thread_2268274   DispatchQueue_1: com.apple.main-thread  (serial)
      928 start  (in libdyld.dylib) + 1  [0x7fff680abcc9]
        928 main  (in swift) + 1283  [0x10387d4d3]
          928 swift::performFrontend(llvm::ArrayRef<char const*>, char const*, void*, swift::FrontendObserver*)  (in swift) + 19914  [0x1038fe86a]
            928 swift::performLLVM(swift::IRGenOptions&, swift::ASTContext&, llvm::Module*, llvm::StringRef, swift::UnifiedStatsReporter*)  (in swift) + 172  [0x103b1b3dc]
              928 swift::performLLVM(swift::IRGenOptions&, swift::DiagnosticEngine*, llvm::sys::SmartMutex<false>*, llvm::GlobalVariable*, llvm::Module*, llvm::TargetMachine*, swift::version::Version const&, llvm::StringRef, swift::UnifiedStatsReporter*)  (in swift) + 9868  [0x103b14c2c]
                928 llvm::legacy::PassManager::run(llvm::Module&)  (in swift) + 1251  [0x107a5b503]
                  928 llvm::FPPassManager::runOnModule(llvm::Module&)  (in swift) + 67  [0x107a4ffb3]
                    928 llvm::FPPassManager::runOnFunction(llvm::Function&)  (in swift) + 1609  [0x107a507f9]
                      928 llvm::MachineFunctionPass::runOnFunction(llvm::Function&)  (in swift) + 311  [0x105e05477]
                        928 llvm::SelectionDAGISel::runOnMachineFunction(llvm::MachineFunction&)  (in swift) + 2667  [0x10544459b]
                          928 llvm::SelectionDAGISel::SelectAllBasicBlocks(llvm::Function const&)  (in swift) + 11699  [0x1054488e3]
                            928 llvm::SelectionDAGISel::CodeGenAndEmitDAG()  (in swift) + 133  [0x10544a225]
                              928 llvm::SelectionDAG::Combine(llvm::CombineLevel, llvm::AAResults*, llvm::CodeGenOpt::Level)  (in swift) + 2289  [0x10523f4f1]
                                927 (anonymous namespace)::DAGCombiner::combine(llvm::SDNode*)  (in swift) + 31  [0x10523fa9f]
                                + 927 (anonymous namespace)::DAGCombiner::visit(llvm::SDNode*)  (in swift) + 6028  [0x10524210c]
                                +   893 (anonymous namespace)::DAGCombiner::visitSTORE(llvm::SDNode*)  (in swift) + 15729  [0x1052ae361]
                                +   ! 889 (anonymous namespace)::DAGCombiner::checkMergeStoreCandidatesForDependencies(llvm::SmallVectorImpl<(anonymous namespace)::DAGCombiner::MemOpLink>&, unsigned int, llvm::SDNode*)  (in swift) + 1110  [0x1052c0d36]
                                +   ! : 464 llvm::SDNode::hasPredecessorHelper(llvm::SDNode const*, llvm::SmallPtrSetImpl<llvm::SDNode const*>&, llvm::SmallVectorImpl<llvm::SDNode const*>&, unsigned int, bool)  (in swift) + 559  [0x104ba2caf]
                                +   ! : | 423 llvm::SmallPtrSetImplBase::insert_imp_big(void const*)  (in swift) + 125,115,...  [0x107b69a4d,0x107b69a43,...]
                                +   ! : | 22 llvm::SmallPtrSetImplBase::insert_imp_big(void const*)  (in swift) + 264  [0x107b69ad8]
                                +   ! : | + 16 _platform_bzero$VARIANT$Haswell  (in libsystem_platform.dylib) + 84,53,...  [0x7fff682a1df4,0x7fff682a1dd5,...]
                                +   ! : | + 6 _platform_memset$VARIANT$Haswell  (in libsystem_platform.dylib) + 19  [0x7fff682a1d73]
                                +   ! : | 12 llvm::SmallPtrSetImplBase::insert_imp_big(void const*)  (in swift) + 231  [0x107b69ab7]
                                +   ! : | + 11 malloc  (in libsystem_malloc.dylib) + 21  [0x7fff68261cf5]
                                +   ! : | + ! 11 malloc_zone_malloc  (in libsystem_malloc.dylib) + 104  [0x7fff68261d7a]
                                +   ! : | + !   7 szone_malloc_should_clear  (in libsystem_malloc.dylib) + 120  [0x7fff682630fc]
                                +   ! : | + !   : 4 small_malloc_should_clear  (in libsystem_malloc.dylib) + 1327,59,...  [0x7fff682636f0,0x7fff682631fc,...]
                                +   ! : | + !   : 3 small_malloc_should_clear  (in libsystem_malloc.dylib) + 279  [0x7fff682632d8]
                                +   ! : | + !   :   2 small_malloc_from_free_list  (in libsystem_malloc.dylib) + 530  [0x7fff68263b23]
                                +   ! : | + !   :   + 1 small_free_list_remove_ptr  (in libsystem_malloc.dylib) + 141  [0x7fff682687e2]
                                +   ! : | + !   :   + 1 small_free_list_remove_ptr_no_clear  (in libsystem_malloc.dylib) + 1216  [0x7fff68268cd2]
                                +   ! : | + !   :   1 small_malloc_from_free_list  (in libsystem_malloc.dylib) + 184  [0x7fff682639c9]
                                +   ! : | + !   4 default_zone_malloc  (in libsystem_malloc.dylib) + 41,38,...  [0x7fff68261df4,0x7fff68261df1,...]
                                +   ! : | + 1 malloc  (in libsystem_malloc.dylib) + 0  [0x7fff68261ce0]
                                +   ! : | 7 llvm::SmallPtrSetImplBase::insert_imp_big(void const*)  (in swift) + 430  [0x107b69b7e]
                                +   ! : |   2 free  (in libsystem_malloc.dylib) + 107  [0x7fff68262a1c]
                                +   ! : |   ! 1 szone_size  (in libsystem_malloc.dylib) + 73  [0x7fff682653a1]
                                +   ! : |   ! : 1 small_size  (in libsystem_malloc.dylib) + 113  [0x7fff68265617]
                                +   ! : |   ! 1 szone_size  (in libsystem_malloc.dylib) + 22  [0x7fff6826536e]
                                +   ! : |   2 free  (in libsystem_malloc.dylib) + 95,449  [0x7fff68262a10,0x7fff68262b72]
                                +   ! : |   2 free_small  (in libsystem_malloc.dylib) + 1552  [0x7fff68265df6]
                                +   ! : |   1 free_small  (in libsystem_malloc.dylib) + 853  [0x7fff68265b3b]
                                +   ! : |     1 small_free_list_remove_ptr_no_clear  (in libsystem_malloc.dylib) + 88  [0x7fff6826886a]
                                +   ! : 425 llvm::SDNode::hasPredecessorHelper(llvm::SDNode const*, llvm::SmallPtrSetImpl<llvm::SDNode const*>&, llvm::SmallVectorImpl<llvm::SDNode const*>&, unsigned int, bool)  (in swift) + 437,535,...  [0x104ba2c35,0x104ba2c97,...]
                                +   ! 3 (anonymous namespace)::DAGCombiner::checkMergeStoreCandidatesForDependencies(llvm::SmallVectorImpl<(anonymous namespace)::DAGCombiner::MemOpLink>&, unsigned int, llvm::SDNode*)  (in swift) + 1177  [0x1052c0d79]
                                +   ! : 2 free_small  (in libsystem_malloc.dylib) + 513,1552  [0x7fff682659e7,0x7fff68265df6]
                                +   ! : 1 free  (in libsystem_malloc.dylib) + 107  [0x7fff68262a1c]
                                +   ! :   1 szone_size  (in libsystem_malloc.dylib) + 45  [0x7fff68265385]
                                +   ! :     1 tiny_size  (in libsystem_malloc.dylib) + 37  [0x7fff68265416]
                                +   ! 1 (anonymous namespace)::DAGCombiner::checkMergeStoreCandidatesForDependencies(llvm::SmallVectorImpl<(anonymous namespace)::DAGCombiner::MemOpLink>&, unsigned int, llvm::SDNode*)  (in swift) + 824  [0x1052c0c18]
                                +   13 (anonymous namespace)::DAGCombiner::visitSTORE(llvm::SDNode*)  (in swift) + 19360  [0x1052af190]
                                +   ! 7 (anonymous namespace)::DAGCombiner::getStoreMergeCandidates(llvm::StoreSDNode*, llvm::SmallVectorImpl<(anonymous namespace)::DAGCombiner::MemOpLink>&, llvm::SDNode*&)::$_42::operator()(llvm::StoreSDNode*, llvm::BaseIndexOffset&, long long&) const  (in swift) + 618  [0x1052bfbda]
                                +   ! : 7 llvm::BaseIndexOffset::match(llvm::SDNode const*, llvm::SelectionDAG const&)  (in swift) + 629,665,...  [0x10543af25,0x10543af49,...]
                                +   ! 3 (anonymous namespace)::DAGCombiner::getStoreMergeCandidates(llvm::StoreSDNode*, llvm::SmallVectorImpl<(anonymous namespace)::DAGCombiner::MemOpLink>&, llvm::SDNode*&)::$_42::operator()(llvm::StoreSDNode*, llvm::BaseIndexOffset&, long long&) const  (in swift) + 1197  [0x1052bfe1d]
                                +   ! : 3 llvm::BaseIndexOffset::match(llvm::SDNode const*, llvm::SelectionDAG const&)  (in swift) + 665  [0x10543af49]
                                +   ! 2 (anonymous namespace)::DAGCombiner::getStoreMergeCandidates(llvm::StoreSDNode*, llvm::SmallVectorImpl<(anonymous namespace)::DAGCombiner::MemOpLink>&, llvm::SDNode*&)::$_42::operator()(llvm::StoreSDNode*, llvm::BaseIndexOffset&, long long&) const  (in swift) + 95  [0x1052bf9cf]
                                +   ! 1 (anonymous namespace)::DAGCombiner::getStoreMergeCandidates(llvm::StoreSDNode*, llvm::SmallVectorImpl<(anonymous namespace)::DAGCombiner::MemOpLink>&, llvm::SDNode*&)::$_42::operator()(llvm::StoreSDNode*, llvm::BaseIndexOffset&, long long&) const  (in swift) + 1272  [0x1052bfe68]
                                +   !   1 llvm::BaseIndexOffset::equalBaseIndex(llvm::BaseIndexOffset const&, llvm::SelectionDAG const&, long long&) const  (in swift) + 7  [0x10543ab27]
                                +   7 (anonymous namespace)::DAGCombiner::visitSTORE(llvm::SDNode*)  (in swift) + 1442,8215,...  [0x1052aab92,0x1052ac607,...]
                                +   4 (anonymous namespace)::DAGCombiner::visitSTORE(llvm::SDNode*)  (in swift) + 16188  [0x1052ae52c]
                                +   ! 4 _platform_memmove$VARIANT$Haswell  (in libsystem_platform.dylib) + 131,244,...  [0x7fff682a1983,0x7fff682a19f4,...]
                                +   2 (anonymous namespace)::DAGCombiner::visitSTORE(llvm::SDNode*)  (in swift) + 8269  [0x1052ac63d]
                                +   ! 2 llvm::BaseIndexOffset::match(llvm::SDNode const*, llvm::SelectionDAG const&)  (in swift) + 72,1311  [0x10543acf8,0x10543b1cf]
                                +   2 (anonymous namespace)::DAGCombiner::visitSTORE(llvm::SDNode*)  (in swift) + 8555  [0x1052ac75b]
                                +   ! 2 realloc  (in libsystem_malloc.dylib) + 253  [0x7fff68263e64]
                                +   !   2 malloc_zone_realloc  (in libsystem_malloc.dylib) + 111  [0x7fff6826509f]
                                +   !     1 szone_realloc  (in libsystem_malloc.dylib) + 806  [0x7fff682663df]
                                +   !     : 1 szone_malloc_should_clear  (in libsystem_malloc.dylib) + 66  [0x7fff682630c6]
                                +   !     :   1 tiny_malloc_should_clear  (in libsystem_malloc.dylib) + 288  [0x7fff68264297]
                                +   !     :     1 tiny_malloc_from_free_list  (in libsystem_malloc.dylib) + 555  [0x7fff68264a3d]
                                +   !     :       1 set_tiny_meta_header_in_use  (in libsystem_malloc.dylib) + 50  [0x7fff68264f69]
                                +   !     1 szone_realloc  (in libsystem_malloc.dylib) + 882  [0x7fff6826642b]
                                +   !       1 free_tiny  (in libsystem_malloc.dylib) + 459  [0x7fff68266d8b]
                                +   !         1 tiny_free_no_lock  (in libsystem_malloc.dylib) + 1111  [0x7fff682672d6]
                                +   !           1 tiny_free_list_add_ptr  (in libsystem_malloc.dylib) + 1042  [0x7fff68267cfc]
                                +   2 (anonymous namespace)::DAGCombiner::visitSTORE(llvm::SDNode*)  (in swift) + 15959  [0x1052ae447]
                                +   ! 2 _platform_memmove$VARIANT$Haswell  (in libsystem_platform.dylib) + 240,244  [0x7fff682a19f0,0x7fff682a19f4]
                                +   1 (anonymous namespace)::DAGCombiner::visitSTORE(llvm::SDNode*)  (in swift) + 887  [0x1052aa967]
                                +   ! 1 llvm::SelectionDAG::InferPtrAlignment(llvm::SDValue) const  (in swift) + 1  [0x105427aa1]
                                +   1 (anonymous namespace)::DAGCombiner::visitSTORE(llvm::SDNode*)  (in swift) + 8584  [0x1052ac778]
                                +   ! 1 malloc  (in libsystem_malloc.dylib) + 21  [0x7fff68261cf5]
                                +   !   1 malloc_zone_malloc  (in libsystem_malloc.dylib) + 80  [0x7fff68261d62]
                                +   1 (anonymous namespace)::DAGCombiner::visitSTORE(llvm::SDNode*)  (in swift) + 14549  [0x1052adec5]
                                +   ! 1 llvm::TargetLoweringBase::getTypeConversion(llvm::LLVMContext&, llvm::EVT) const  (in swift) + 1802  [0x105f7307a]
                                +   1 (anonymous namespace)::DAGCombiner::visitSTORE(llvm::SDNode*)  (in swift) + 26474  [0x1052b0d5a]
                                +     1 llvm::MetadataTracking::track(void*, llvm::Metadata&, llvm::PointerUnion<llvm::MetadataAsValue*, llvm::Metadata*>)  (in swift) + 0  [0x107a5f2f0]
                                1 (anonymous namespace)::DAGCombiner::combine(llvm::SDNode*)  (in swift) + 146  [0x10523fb12]
                                  1 llvm::AArch64TargetLowering::PerformDAGCombine(llvm::SDNode*, llvm::TargetLowering::DAGCombinerInfo&) const  (in swift) + 7761  [0x1050bebb1]
                                    1 llvm::AArch64Subtarget::supportsAddressTopByteIgnored() const  (in swift) + 128  [0x105152950]

Total number in stack (recursive counted multiple, when >=5):

Sort by top of stack, same collapsed (when >= 5):
        llvm::SDNode::hasPredecessorHelper(llvm::SDNode const*, llvm::SmallPtrSetImpl<llvm::SDNode const*>&, llvm::SmallVectorImpl<llvm::SDNode const*>&, unsigned int, bool)  (in swift)        425
        llvm::SmallPtrSetImplBase::insert_imp_big(void const*)  (in swift)        423
        _platform_bzero$VARIANT$Haswell  (in libsystem_platform.dylib)        16
        llvm::BaseIndexOffset::match(llvm::SDNode const*, llvm::SelectionDAG const&)  (in swift)        12
        (anonymous namespace)::DAGCombiner::visitSTORE(llvm::SDNode*)  (in swift)        7
        _platform_memmove$VARIANT$Haswell  (in libsystem_platform.dylib)        6
        _platform_memset$VARIANT$Haswell  (in libsystem_platform.dylib)        6

Binary Images:
       0x10385b000 -        0x1085c3ffb +swift (1103.0.32.1) <BD0CD6C2-B423-314B-91B9-D07CD87D912B> /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/swift
       0x113ada000 -        0x113b6beff  dyld (750.5) <1F893B81-89A5-3502-8510-95B97B9F730D> /usr/lib/dyld
    0x7fff65091000 -     0x7fff65092fff  libSystem.B.dylib (1281.100.1) <DB8310F1-272D-3533-A840-3B390AF55C26> /usr/lib/libSystem.B.dylib
    0x7fff65377000 -     0x7fff653c9fff  libc++.1.dylib (902.1) <08199809-33CA-321E-9B9D-FD5B2BC64580> /usr/lib/libc++.1.dylib
    0x7fff653ca000 -     0x7fff653dfffb  libc++abi.dylib (902) <1C880020-396D-3F91-BE27-5A09A9239F68> /usr/lib/libc++abi.dylib
    0x7fff65e06000 -     0x7fff65e23fff  libedit.3.dylib (55) <A41E499B-D031-38EA-8D1D-F271EED15830> /usr/lib/libedit.3.dylib
    0x7fff66877000 -     0x7fff668a6fff  libncurses.5.4.dylib (57) <6BD6F430-C8B3-39D8-87B5-2C16E6578FD5> /usr/lib/libncurses.5.4.dylib
    0x7fff66ef1000 -     0x7fff66f24fde  libobjc.A.dylib (787.1) <20AC082F-2DB7-3974-A2D4-8C5E01787584> /usr/lib/libobjc.A.dylib
    0x7fff675cd000 -     0x7fff675dfff3  libz.1.dylib (76) <6A449C6A-DF88-36C1-8F2D-DB9A808263B5> /usr/lib/libz.1.dylib
    0x7fff67e8d000 -     0x7fff67e92ff3  libcache.dylib (83) <5F90FFCE-403B-3724-991D-BA32401D99C5> /usr/lib/system/libcache.dylib
    0x7fff67e93000 -     0x7fff67e9efff  libcommonCrypto.dylib (60165) <C7A5E3F7-1E5A-3785-875A-B6647082B614> /usr/lib/system/libcommonCrypto.dylib
    0x7fff67e9f000 -     0x7fff67ea6fff  libcompiler_rt.dylib (101.2) <A517E149-2D25-3C04-BCEF-F69149C85B18> /usr/lib/system/libcompiler_rt.dylib
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    0x7fff67eb1000 -     0x7fff67f43fe3  libcorecrypto.dylib (866.100.30) <FCDEC0D1-8C30-3989-BDD1-996BBC715C29> /usr/lib/system/libcorecrypto.dylib
    0x7fff68050000 -     0x7fff68090ff0  libdispatch.dylib (1173.100.2) <EB592997-B11C-3AB3-85B1-F725F3D0B412> /usr/lib/system/libdispatch.dylib
    0x7fff68091000 -     0x7fff680c7fff  libdyld.dylib (750.5) <D2A07EF5-A64B-3692-BE13-89DAA2EC5E80> /usr/lib/system/libdyld.dylib
    0x7fff680c8000 -     0x7fff680c8ffb  libkeymgr.dylib (30) <CC5A2B43-770B-3C6C-BA10-AA3A6B4A142D> /usr/lib/system/libkeymgr.dylib
    0x7fff680d6000 -     0x7fff680d6ff7  liblaunch.dylib (1738.100.39) <A7FF7357-600F-3014-8C28-A4F367717E8D> /usr/lib/system/liblaunch.dylib
    0x7fff680d7000 -     0x7fff680dcff7  libmacho.dylib (959.0.1) <D8FED478-25A2-3844-AE4B-A5C9F9827615> /usr/lib/system/libmacho.dylib
    0x7fff680dd000 -     0x7fff680dfff3  libquarantine.dylib (110.40.3) <51E0304F-AB11-3BF7-99DC-BB916CC9088B> /usr/lib/system/libquarantine.dylib
    0x7fff680e0000 -     0x7fff680e1ff7  libremovefile.dylib (48) <078F29AB-26BA-3493-BCAA-E1E75A187521> /usr/lib/system/libremovefile.dylib
    0x7fff680e2000 -     0x7fff680f9ff3  libsystem_asl.dylib (377.60.2) <0F1BAC19-2AE0-3F8E-9B90-AACF819B2BF7> /usr/lib/system/libsystem_asl.dylib
    0x7fff680fa000 -     0x7fff680faff7  libsystem_blocks.dylib (74) <32224AFF-C06F-3279-B753-097194EDEF49> /usr/lib/system/libsystem_blocks.dylib
    0x7fff680fb000 -     0x7fff68182fff  libsystem_c.dylib (1353.100.2) <4F5EED22-4D46-3F04-8C64-C492CDAD70EB> /usr/lib/system/libsystem_c.dylib
    0x7fff68183000 -     0x7fff68186ffb  libsystem_configuration.dylib (1061.101.1) <2A2C778D-07EB-35C7-A954-8BF8FD74BD75> /usr/lib/system/libsystem_configuration.dylib
    0x7fff68187000 -     0x7fff6818afff  libsystem_coreservices.dylib (114) <FDA41CC4-170A-3D93-85BD-838A563B03C4> /usr/lib/system/libsystem_coreservices.dylib
    0x7fff6818b000 -     0x7fff68193fff  libsystem_darwin.dylib (1353.100.2) <B567B86D-8818-38A4-A861-03EB83B55867> /usr/lib/system/libsystem_darwin.dylib
    0x7fff68194000 -     0x7fff6819bfff  libsystem_dnssd.dylib (1096.100.3) <7C690DF5-E119-33FB-85CD-9EFC67A36E40> /usr/lib/system/libsystem_dnssd.dylib
    0x7fff6819c000 -     0x7fff6819dffb  libsystem_featureflags.dylib (17) <415D83EF-084C-3485-B757-53001870EA94> /usr/lib/system/libsystem_featureflags.dylib
    0x7fff6819e000 -     0x7fff681ebff7  libsystem_info.dylib (538) <17049D3F-C798-3651-B391-1551FC699D3E> /usr/lib/system/libsystem_info.dylib
    0x7fff681ec000 -     0x7fff68218ff7  libsystem_kernel.dylib (6153.101.6) <E76440E1-D1E8-3D9A-8B47-D01F554FF1C4> /usr/lib/system/libsystem_kernel.dylib
    0x7fff68219000 -     0x7fff68260fff  libsystem_m.dylib (3178) <74741FA8-5C29-3241-9046-4FC91C6A6D4A> /usr/lib/system/libsystem_m.dylib
    0x7fff68261000 -     0x7fff68288fff  libsystem_malloc.dylib (283.100.5) <97833239-2F83-3AEB-A426-0593997C8A54> /usr/lib/system/libsystem_malloc.dylib
    0x7fff68289000 -     0x7fff68296ffb  libsystem_networkextension.dylib (1095.100.29) <C9E988B2-6A18-35C0-9577-63201E9D6018> /usr/lib/system/libsystem_networkextension.dylib
    0x7fff68297000 -     0x7fff682a0ff7  libsystem_notify.dylib (241.100.2) <E405F84B-BD4F-3874-9755-CB3EC86E18D5> /usr/lib/system/libsystem_notify.dylib
    0x7fff682a1000 -     0x7fff682a9fef  libsystem_platform.dylib (220.100.1) <6EF12F34-C33F-36BF-9A9A-2A35EA19EFE0> /usr/lib/system/libsystem_platform.dylib
    0x7fff682aa000 -     0x7fff682b4fff  libsystem_pthread.dylib (416.100.3) <A8514582-E000-3854-911A-0A73D2C79600> /usr/lib/system/libsystem_pthread.dylib
    0x7fff682b5000 -     0x7fff682b9ff3  libsystem_sandbox.dylib (1217.101.2) <E9D78CDE-FB67-32E7-BABC-9EFC23AA0DC6> /usr/lib/system/libsystem_sandbox.dylib
    0x7fff682ba000 -     0x7fff682bcfff  libsystem_secinit.dylib (62.100.2) <AAC639E5-7103-3366-A602-8FC6944E2C13> /usr/lib/system/libsystem_secinit.dylib
    0x7fff682bd000 -     0x7fff682c4ffb  libsystem_symptoms.dylib (1238.100.26) <487B92DE-45F9-39F9-A478-89BBD478157D> /usr/lib/system/libsystem_symptoms.dylib
    0x7fff682c5000 -     0x7fff682dbff2  libsystem_trace.dylib (1147.100.8) <BB90B1FD-8C09-3DF4-BD8B-9E4AEADFEA2B> /usr/lib/system/libsystem_trace.dylib
    0x7fff682dd000 -     0x7fff682e2ff7  libunwind.dylib (35.4) <CC87C836-BE9D-334E-A0E6-0297D52E9D73> /usr/lib/system/libunwind.dylib
    0x7fff682e3000 -     0x7fff68318ffe  libxpc.dylib (1738.100.39) <32B0E31E-9DA3-328B-A962-BC9591B93537> /usr/lib/system/libxpc.dylib
Sample analysis of process 54572 written to file /dev/stdout