Provide symbol mangling for dependencies about cocoapods-packager

[neonichu]

OK, sounds just like the main purpose of -packager except for not packaging the dependencies. I am thinking this should be an option to the standard action, like --omit-dependencies or so.

[segiddins]

I think omitting the dependencies is the killer feature of packager (and is what this issue is about).

[blakewatters]

@segiddins Omitting dependencies isn’t what you really want. What you want to do is include all the dependencies exactly as specified but obfuscate all of the symbols exported by the dependencies.

For example, consider a closed source library that uses FMDB internally. If a user of that library also wishes to use FMDB, you’d want to allow two copies of it to exist within the application address space without affecting one another. If you omit the dependencies, then you aren’t necessarily producing a compatible runtime environment for the closed source library. And the developers of that library aren’t going to want to have to try to support a version of their package that has been statically linked against an arbitrary combination of dependencies. The private library dependencies themselves shouldn’t even be public knowledge — you’ll just want to link FooLib.a and have it work without knowing what its leveraging internally.

[AliSoftware]

@blakewatters I understand your arguments, but the problem with this approach is that if your closed source library uses FMDB v2.3 (let's say, the latest version) and the user appends to wish to use FMDB 2.3 too (which seems reasonable), you will have two copies of the compiled code in your final binary : one embedded in your closed source library, with FMDB's symbols obfuscated, and the other one from the app itself.

This means that you will have duplication of your executable code and a bigger application binary at the end. If it only concerns a small dependency, it may be ok, but if you drag a whole dependency tree with a lot of internal libraries, you may end up with an app 3 times bigger…

Actually maybe the best choice for cocoapods-packager is to propose both options, not including dependencies by default, and including then but obfuscating their symbols when a flag --with-dependencies is given?

[alloy]

Actually maybe the best choice for cocoapods-packager is to propose both options, not including dependencies by default, and including then but obfuscating their symbols when a flag --with-dependencies is given?

While this would be great, I don’t see a reliable way to do this. Are there standard tools that can reliably mangle symbols taking Objective-C semantics into account? (E.g. class/category/method names.)

[blakewatters]

@AliSoftware I’d argue that its exactly what you’d want. Imagine that you’ve integrated a third-party framework (libAwesome) that uses FMDB v2.3 and you also build your app against v2.3. Time passes and you wish to upgrade to FMDB v3.0 to get access to some whiz bang killer new feature, but libAwesome is in maintenance mode pending a major release 3 months away. Your application development decisions are now completely dominated by the implementation details of a third-party.

Responsible third-party SDK developers should be mindful of the number of dependencies they use and try to be respectful in the footprint they impose on applications adopting their work. But I also don’t think that the footprint would be that significant in the larger scheme of things. Image assets are going to add up much faster than stripped optimized code segments. I’d wager that most developers would gladly sacrifice 800k of binary space on potentially duplicated code segments for autonomy and isolation from third-party implementation details.

[blakewatters]

@alloy the nm utility available with the Xcode build change lists the symbol table for object files. Below is a dump of the symbols from a Pod build of TransitionKit, which we are using internally within LayerKit. It captures all the classes, categories, methods, and constants exported. If these symbols were aliased by injecting pre-processor definitions into the PCH when the target was built I think you could completely isolate the dependency:

libPods-Unit Tests-TransitionKit.a(Pods-Unit Tests-TransitionKit-dummy.o):
         U _OBJC_CLASS_$_NSObject
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         U _OBJC_METACLASS_$_NSObject
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         U __objc_empty_cache
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libPods-Unit Tests-TransitionKit.a(TKEvent.o):
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libPods-Unit Tests-TransitionKit.a(TKState.o):
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00002714 s +[TKState stateWithName:].eh
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libPods-Unit Tests-TransitionKit.a(TKStateMachine.o):
00000000 t +[TKStateMachine keyPathsForValuesAffectingValueForKey:]
00008d68 s +[TKStateMachine keyPathsForValuesAffectingValueForKey:].eh
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00008f28 s -[TKStateMachine activate].eh
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00008e48 s -[TKStateMachine addStates:].eh
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00008f48 s -[TKStateMachine canFireEvent:].eh
00003f40 t -[TKStateMachine copyWithZone:]
00008fc8 s -[TKStateMachine copyWithZone:].eh
000049f0 t -[TKStateMachine currentState]
00009004 s -[TKStateMachine currentState].eh
00000400 t -[TKStateMachine description]
00008da8 s -[TKStateMachine description].eh
00003d20 t -[TKStateMachine encodeWithCoder:]
00008fa8 s -[TKStateMachine encodeWithCoder:].eh
00001e10 t -[TKStateMachine eventNamed:]
00008f08 s -[TKStateMachine eventNamed:].eh
00001450 t -[TKStateMachine events]
00008ea8 s -[TKStateMachine events].eh
000027e0 t -[TKStateMachine fireEvent:userInfo:error:]
00008f68 s -[TKStateMachine fireEvent:userInfo:error:].eh
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00008d88 s -[TKStateMachine init].eh
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00008fe8 s -[TKStateMachine initialState].eh
00004b40 t -[TKStateMachine isActive]
000090ac s -[TKStateMachine isActive].eh
00001190 t -[TKStateMachine isInState:]
00008e88 s -[TKStateMachine isInState:].eh
00004bb0 t -[TKStateMachine lock]
000090e4 s -[TKStateMachine lock].eh
00004ad0 t -[TKStateMachine mutableEvents]
00009074 s -[TKStateMachine mutableEvents].eh
00004a60 t -[TKStateMachine mutableStates]
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libPods-Unit Tests-TransitionKit.a(TKTransition.o):
00000000 t +[TKTransition transitionForEvent:fromState:inStateMachine:userInfo:]
00001940 s +[TKTransition transitionForEvent:fromState:inStateMachine:userInfo:].eh
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``

[alloy]

The problem is that since Objective-C has a dynamic runtime, we cannot reliably know if we’ve renamed everything. E.g.

[object performSelector:NSStringFromSelector([NSString stringWithFormat:@"perform%@", action])];

[segiddins]

We actually wouldn't need to rename selectors, since they are uniqued. Just classes and protocols and exported c function names.

-Samuel E. Giddins

On May 16, 2014, at 12:45 PM, Eloy Durán [email protected] wrote:

The problem is that since Objective-C has a dynamic runtime, we cannot reliably know if we’ve renamed everything. E.g.

[object performSelector:NSStringFromSelector([NSString stringWithFormat:@"perform%@", action])];
—
Reply to this email directly or view it on GitHub.

[alloy]

@segiddins Multiple methods on the same class (from e.g. categories) with the same selector would still pose a problem.

[blakewatters]

I don’t think you actually need to rename methods except for those exported on categories. And it would be the responsibility of whoever is creating the package to ensure that it works as intended

[alloy]

it would be the responsibility of whoever is creating the package to ensure that it works as intended

While this is definitely true, it means we cannot build such a package which is guaranteed to work out of the box. I’m slightly afraid that that will lead to people doing the wrong thing.

Having said that, I don’t see an alternative, and it would indeed be great if we can automate it as much as possible. I guess time will have to tell.

[AliSoftware]

Never used it in practice so not sure it applies here, but wouldn't it be a use case where @compatibility_alias could be useful?

[alloy]

@AliSoftware Nope, that would make both names be usable in the runtime to refer to the same class instance.

[blakewatters]

I think if you invoke the packager with the --mangle-dependency-symbols (or whatever) then we just emit a warning indicating that symbol integrity cannot be programmatically guaranteed. In practice the only folks who will be doing this are those building closed source libraries with open source dependencies. They should have a handle on their dependencies and have a commercial grade QA process for the binaries anyway.

The concern around category methods really doesn’t bother me much. I’m don’t have any category methods introduced in any of my dependencies. IMHO category methods have been overused in the community and should be avoided if you are shipping closed source bits. And if you do have them and follow prefixing conventions then they’ll be easy to alias away. That should narrow the dynamic invocation concerns to category methods that are dynamically invoked from selectors composed via strings. That’s a pretty narrow corner.

[neonichu]

Renamed this to reflect that this is actually just about implementing the symbol mangling

[blakewatters]

Here is my Podspec. Given this, I want to be able to generate a framework, static library + headers, and a Podspec for installing the public version of the bits:

Pod::Spec.new do |s|
  s.name     = 'LayerKit'
  s.version  = '0.50.0'
  s.license  = 'Commercial'
  s.summary  = 'LayerKit is the iOS client interface for the Layer communications cloud.'
  s.homepage = 'https://github.com/layerhq/LayerKit'
  s.authors  = { 'Blake Watters' => '[email protected]', 'Klemen Verdnik' => '[email protected]' }
  s.source   = { :git => 'https://github.com/layerhq/LayerKit.git', :tag => "v#{s.version}" }  
  s.requires_arc = true
  s.ios.deployment_target = '7.0'

  s.source_files = 'Code/**/*.{h,m}'
  s.public_header_files = 'Code/*.h'
  s.private_header_files = 'Code/Private/**/*.h'
  s.prefix_header_file = 'Code/Private/LayerKit-Prefix.pch'

  s.libraries = 'sqlite3', 'z'
  s.ios.frameworks = 'CFNetwork', 'Security', 'MobileCoreServices', 'SystemConfiguration'

  s.prefix_header_contents = <<-PCH
#import <DDLog.h>
#include "LYRLog.h"
PCH

  s.ios.deployment_target = '5.0'
  s.osx.deployment_target = '10.7'

  # Dependencies
  s.dependency 'CocoaSPDY', '~> 1.0.1'
  s.dependency 'CocoaLumberjack', '~> 1.8.1'
  s.dependency 'FMDB', '~> 2.2'
  s.dependency 'layer-thrift', '~> 0.50.0'
  s.dependency 'TransitionKit', '~> 2.1.0'
end

[segiddins]

Is this still needed with the new modules stuff?

[neonichu]

I'm pretty sure it is.

[neonichu]

Implemented in 4259238

[Whirlwind]

I use cocoapods-packager v1.1.0 and Cocoapods v0.35.0, but I found the symbols still exist.

My pod spec:

  s.dependency 'MTDates', '0.14.0'

I run pod package testFramework.podspec, then I found the size of binary is 1MB!!

I use the nm to test it.

$ nm TestFramework

TestFramework(NSDate+MTDates.o):
0000000000008fae t +[NSDate(MTDates) mt_calendar]
0000000000009065 t +[NSDate(MTDates) mt_components]
0000000000001234 t +[NSDate(MTDates) mt_dateFromComponents:]
00000000000004e7 t +[NSDate(MTDates) mt_dateFromISOString:]
0000000000000865 t +[NSDate(MTDates) mt_dateFromString:usingFormat:]
00000000000009e6 t +[NSDate(MTDates) mt_dateFromYear:month:day:]
0000000000000adb t +[NSDate(MTDates) mt_dateFromYear:month:day:hour:minute:]
0000000000000bc5 t +[NSDate(MTDates) mt_dateFromYear:month:day:hour:minute:second:]
0000000000000d2a t +[NSDate(MTDates) mt_dateFromYear:week:weekday:]
0000000000000e1f t +[NSDate(MTDates) mt_dateFromYear:week:weekday:hour:minute:]
0000000000000f09 t +[NSDate(MTDates) mt_dateFromYear:week:weekday:hour:minute:second:]
00000000000084c9 t +[NSDate(MTDates) mt_datesCollectionFromDate:untilDate:]
0000000000001562 t +[NSDate(MTDates) mt_endOfToday]
00000000000016e4 t +[NSDate(MTDates) mt_endOfTomorrow]
0000000000001623 t +[NSDate(MTDates) mt_endOfYesterday]
0000000000008dd5 t +[NSDate(MTDates) mt_maxValueForUnit:]
0000000000008d1c t +[NSDate(MTDates) mt_minValueForUnit:]
0000000000001aa9 t +[NSDate(MTDates) mt_monthlySymbols]
0000000000008e92 t +[NSDate(MTDates) mt_prepareDefaults]
000000000000921f t +[NSDate(MTDates) mt_reset]
000000000000017b t +[NSDate(MTDates) mt_setCalendarIdentifier:]
00000000000003bb t +[NSDate(MTDates) mt_setFirstDayOfWeek:]
00000000000073be t +[NSDate(MTDates) mt_setFormatterDateStyle:]
0000000000007479 t +[NSDate(MTDates) mt_setFormatterTimeStyle:]
000000000000023b t +[NSDate(MTDates) mt_setLocale:]
00000000000002fb t +[NSDate(MTDates) mt_setTimeZone:]
0000000000000451 t +[NSDate(MTDates) mt_setWeekNumberingSystem:]
0000000000000000 t +[NSDate(MTDates) mt_sharedFormatter]
00000000000019e8 t +[NSDate(MTDates) mt_shortMonthlySymbols]
00000000000017a5 t +[NSDate(MTDates) mt_shortWeekdaySymbols]
000000000000131f t +[NSDate(MTDates) mt_startOfToday]
00000000000014a1 t +[NSDate(MTDates) mt_startOfTomorrow]
00000000000013e0 t +[NSDate(MTDates) mt_startOfYesterday]
0000000000001b6a t +[NSDate(MTDates) mt_veryShortMonthlySymbols]
0000000000001927 t +[NSDate(MTDates) mt_veryShortWeekdaySymbols]
0000000000001866 t +[NSDate(MTDates) mt_weekdaySymbols]
00000000000092d8 t +[NSDate(MTDates) sharedRecursiveLock]
0000000000021800 b +[NSDate(MTDates) sharedRecursiveLock].lock
0000000000021808 b +[NSDate(MTDates) sharedRecursiveLock].onceToken
0000000000002568 t -[NSDate(MTDates) mt_components]
000000000000106e t -[NSDate(MTDates) mt_dateByAddingYears:months:weeks:days:hours:minutes:seconds:]
0000000000004c9f t -[NSDate(MTDates) mt_dateDaysAfter:]
0000000000004bce t -[NSDate(MTDates) mt_dateDaysBefore:]
00000000000056e2 t -[NSDate(MTDates) mt_dateHoursAfter:]
0000000000005615 t -[NSDate(MTDates) mt_dateHoursBefore:]
0000000000006138 t -[NSDate(MTDates) mt_dateMinutesAfter:]
000000000000606b t -[NSDate(MTDates) mt_dateMinutesBefore:]
0000000000003797 t -[NSDate(MTDates) mt_dateMonthsAfter:]
00000000000036c5 t -[NSDate(MTDates) mt_dateMonthsBefore:]
00000000000067c1 t -[NSDate(MTDates) mt_dateSecondsAfter:]
00000000000066f4 t -[NSDate(MTDates) mt_dateSecondsBefore:]
0000000000004247 t -[NSDate(MTDates) mt_dateWeeksAfter:]
0000000000004176 t -[NSDate(MTDates) mt_dateWeeksBefore:]
0000000000002d74 t -[NSDate(MTDates) mt_dateYearsAfter:]
0000000000002ca2 t -[NSDate(MTDates) mt_dateYearsBefore:]
0000000000002131 t -[NSDate(MTDates) mt_dayOfMonth]
0000000000001de9 t -[NSDate(MTDates) mt_dayOfYear]
00000000000089c3 t -[NSDate(MTDates) mt_daysInCurrentMonth]
0000000000008b2b t -[NSDate(MTDates) mt_daysInNextMonth]
0000000000008a77 t -[NSDate(MTDates) mt_daysInPreviousMonth]
0000000000004d6d t -[NSDate(MTDates) mt_daysSinceDate:]
0000000000004e77 t -[NSDate(MTDates) mt_daysUntilDate:]
000000000000488f t -[NSDate(MTDates) mt_endOfCurrentDay]
00000000000052e0 t -[NSDate(MTDates) mt_endOfCurrentHour]
0000000000005d36 t -[NSDate(MTDates) mt_endOfCurrentMinute]
0000000000003385 t -[NSDate(MTDates) mt_endOfCurrentMonth]
0000000000003e37 t -[NSDate(MTDates) mt_endOfCurrentWeek]
0000000000002962 t -[NSDate(MTDates) mt_endOfCurrentYear]
0000000000004979 t -[NSDate(MTDates) mt_endOfNextDay]
00000000000053c7 t -[NSDate(MTDates) mt_endOfNextHour]
0000000000005e1d t -[NSDate(MTDates) mt_endOfNextMinute]
000000000000346f t -[NSDate(MTDates) mt_endOfNextMonth]
0000000000003f21 t -[NSDate(MTDates) mt_endOfNextWeek]
0000000000002a4c t -[NSDate(MTDates) mt_endOfNextYear]
00000000000047cf t -[NSDate(MTDates) mt_endOfPreviousDay]
0000000000005220 t -[NSDate(MTDates) mt_endOfPreviousHour]
0000000000005c76 t -[NSDate(MTDates) mt_endOfPreviousMinute]
00000000000032c5 t -[NSDate(MTDates) mt_endOfPreviousMonth]
0000000000003d77 t -[NSDate(MTDates) mt_endOfPreviousWeek]
00000000000028a2 t -[NSDate(MTDates) mt_endOfPreviousYear]
0000000000002210 t -[NSDate(MTDates) mt_hourOfDay]
000000000000861e t -[NSDate(MTDates) mt_hoursInCurrentDayAsDatesCollection]
00000000000057ac t -[NSDate(MTDates) mt_hoursSinceDate:]
00000000000058b6 t -[NSDate(MTDates) mt_hoursUntilDate:]
0000000000008bdf t -[NSDate(MTDates) mt_inTimeZone:]
0000000000006a9f t -[NSDate(MTDates) mt_isAfter:]
0000000000006b5f t -[NSDate(MTDates) mt_isBefore:]
00000000000072a3 t -[NSDate(MTDates) mt_isBetweenDate:andDate:]
0000000000008795 t -[NSDate(MTDates) mt_isInAM]
0000000000006c1f t -[NSDate(MTDates) mt_isOnOrAfter:]
0000000000006cf1 t -[NSDate(MTDates) mt_isOnOrBefore:]
000000000000882e t -[NSDate(MTDates) mt_isStartOfAnHour]
000000000000707b t -[NSDate(MTDates) mt_isWithinSameDay:]
000000000000717e t -[NSDate(MTDates) mt_isWithinSameHour:]
0000000000006e8f t -[NSDate(MTDates) mt_isWithinSameMonth:]
0000000000006f70 t -[NSDate(MTDates) mt_isWithinSameWeek:]
0000000000006dc3 t -[NSDate(MTDates) mt_isWithinSameYear:]
00000000000022ef t -[NSDate(MTDates) mt_minuteOfHour]
0000000000006202 t -[NSDate(MTDates) mt_minutesSinceDate:]
000000000000630c t -[NSDate(MTDates) mt_minutesUntilDate:]
0000000000002052 t -[NSDate(MTDates) mt_monthOfYear]
0000000000003866 t -[NSDate(MTDates) mt_monthsSinceDate:]
0000000000003970 t -[NSDate(MTDates) mt_monthsUntilDate:]
0000000000004b04 t -[NSDate(MTDates) mt_oneDayNext]
0000000000004a39 t -[NSDate(MTDates) mt_oneDayPrevious]
000000000000554e t -[NSDate(MTDates) mt_oneHourNext]
0000000000005487 t -[NSDate(MTDates) mt_oneHourPrevious]
0000000000005fa4 t -[NSDate(MTDates) mt_oneMinuteNext]
0000000000005edd t -[NSDate(MTDates) mt_oneMinutePrevious]
00000000000035fb t -[NSDate(MTDates) mt_oneMonthNext]
000000000000352f t -[NSDate(MTDates) mt_oneMonthPrevious]
000000000000662d t -[NSDate(MTDates) mt_oneSecondNext]
0000000000006566 t -[NSDate(MTDates) mt_oneSecondPrevious]
00000000000040ac t -[NSDate(MTDates) mt_oneWeekNext]
0000000000003fe1 t -[NSDate(MTDates) mt_oneWeekPrevious]
0000000000002bd8 t -[NSDate(MTDates) mt_oneYearNext]
0000000000002b0c t -[NSDate(MTDates) mt_oneYearPrevious]
00000000000023ce t -[NSDate(MTDates) mt_secondOfMinute]
00000000000024ad t -[NSDate(MTDates) mt_secondsIntoDay]
000000000000688b t -[NSDate(MTDates) mt_secondsSinceDate:]
0000000000006995 t -[NSDate(MTDates) mt_secondsUntilDate:]
00000000000045e9 t -[NSDate(MTDates) mt_startOfCurrentDay]
0000000000005041 t -[NSDate(MTDates) mt_startOfCurrentHour]
0000000000005a80 t -[NSDate(MTDates) mt_startOfCurrentMinute]
0000000000003117 t -[NSDate(MTDates) mt_startOfCurrentMonth]
0000000000003b3a t -[NSDate(MTDates) mt_startOfCurrentWeek]
00000000000026f4 t -[NSDate(MTDates) mt_startOfCurrentYear]
000000000000470f t -[NSDate(MTDates) mt_startOfNextDay]
0000000000005160 t -[NSDate(MTDates) mt_startOfNextHour]
0000000000005bb6 t -[NSDate(MTDates) mt_startOfNextMinute]
0000000000003205 t -[NSDate(MTDates) mt_startOfNextMonth]
00000000000064be t -[NSDate(MTDates) mt_startOfNextSecond]
0000000000003cb7 t -[NSDate(MTDates) mt_startOfNextWeek]
00000000000027e2 t -[NSDate(MTDates) mt_startOfNextYear]
0000000000004529 t -[NSDate(MTDates) mt_startOfPreviousDay]
0000000000004f81 t -[NSDate(MTDates) mt_startOfPreviousHour]
00000000000059c0 t -[NSDate(MTDates) mt_startOfPreviousMinute]
0000000000003057 t -[NSDate(MTDates) mt_startOfPreviousMonth]
0000000000006416 t -[NSDate(MTDates) mt_startOfPreviousSecond]
0000000000003a7a t -[NSDate(MTDates) mt_startOfPreviousWeek]
0000000000002634 t -[NSDate(MTDates) mt_startOfPreviousYear]
00000000000079bf t -[NSDate(MTDates) mt_stringFromDateWithAMPMSymbol]
0000000000007bc0 t -[NSDate(MTDates) mt_stringFromDateWithFormat:localized:]
0000000000007913 t -[NSDate(MTDates) mt_stringFromDateWithFullMonth]
0000000000007b14 t -[NSDate(MTDates) mt_stringFromDateWithFullWeekdayTitle]
0000000000007e4e t -[NSDate(MTDates) mt_stringFromDateWithGreatestComponentsForSecondsPassed:]
0000000000008148 t -[NSDate(MTDates) mt_stringFromDateWithGreatestComponentsUntilDate:]
00000000000077a8 t -[NSDate(MTDates) mt_stringFromDateWithHourAndMinuteFormat:]
0000000000007cf6 t -[NSDate(MTDates) mt_stringFromDateWithISODateTime]
0000000000007867 t -[NSDate(MTDates) mt_stringFromDateWithShortMonth]
0000000000007a68 t -[NSDate(MTDates) mt_stringFromDateWithShortWeekdayTitle]
00000000000075fb t -[NSDate(MTDates) mt_stringValueWithDateStyle:timeStyle:]
0000000000007534 t -[NSDate(MTDates) mt_stringValue]
0000000000001eae t -[NSDate(MTDates) mt_weekOfMonth]
0000000000001d0a t -[NSDate(MTDates) mt_weekOfYear]
0000000000001f8d t -[NSDate(MTDates) mt_weekdayOfWeek]
000000000000890f t -[NSDate(MTDates) mt_weekdayStartOfCurrentMonth]
0000000000004315 t -[NSDate(MTDates) mt_weeksSinceDate:]
000000000000441f t -[NSDate(MTDates) mt_weeksUntilDate:]
0000000000001c2b t -[NSDate(MTDates) mt_year]
0000000000002e43 t -[NSDate(MTDates) mt_yearsSinceDate:]
0000000000002f4d t -[NSDate(MTDates) mt_yearsUntilDate:]

So the symbols still exist, and the dependency be packaged.

[Whirlwind]

I found the size of binary is same to the --no-mangle.

[neonichu]

Indeed, categories cannot be mangled, otherwise they would extend a class that doesn't exist.

[Whirlwind]

I think the categories should be mangled.
I have a repo to manage all categories, and my libraries would dependency it.If the categories are not be mangled, I will get many conflict for the categories.

If the version of the categories is different, so I will find that some categories override the same name function categories.

[AliSoftware]

I'm not sure how symbol mangling works in cocoapods-packager ATM, but what IMHO, one would expect:

• Methods in categories to be mangled, same as methods in classes of the pod, to avoid name conflicts on methods
• Categories applying to a class that is itself defined it the pod to have its related class it applies on mangled as well, as the class name itself will be mangled anyway
• Categories applying to a class that is defined outside a pod (typically one of Apple's class) not to mangle the class it applies on

---

So for example:

// Inside FooPod, before mangling:
@interface FooPod
- (void)baseMethod;
@end

@interface FooPod(MyCategory)
- (void)categoryMethod;
@end

@interface NSString(FooAdditions)
- (void)additionMethod
@end

Should end up compiled as:

// Inside FooPod, after mangling:
@interface ManglePrefix-FooPod
- (void)manglePrefix-baseMethod;
@end

@interface ManglePrefix-FooPod(MyCategory)
- (void)manglePrefix-categoryMethod;
@end

@interface NSString(FooAdditions)
- (void)manglePrefix-additionMethod
@end

[neonichu]

OK, I see the unmatched expectation now. The packager does not mangle selectors and will not be able to using the current approach (preprocessor defines). Personally, I don't think it is a good idea for libraries to contain categories, because conflict issues reach far beyond the packager. Nevertheless, I'll open a separate issue to document that this is currently not done.

[Whirlwind]

I found that if I build the library without the OTHER_LDFLAGS in Pods.xcconfig, the library will be compile well and without any dependency.

It said that I only need the HEADER_SEARCH_PATHS, so every thing will be ok.

[Whirlwind]

Do nobody agree with me?