Issues with archiving iOS project: libz.dylib not found

Question

I have issues when making an archive from a (legacy) iOS project. While archiving I get the following error:

Libtool /Users/appcell/Library/Developer/Xcode/DerivedData/elho-ctuevlyyxtyssvblxkqezbfgdtyq/Build/Intermediates/ArchiveIntermediates/Elho/IntermediateBuildFilesPath/PSPDFKit-lib.build/Release-iphoneos/PSPDFKit.build/Objects-normal/armv7/libPSPDFKit.a normal armv7
cd /Users/appcell/Documents/Projects/Elho/Libraries/PSPDFKit
export IPHONEOS_DEPLOYMENT_TARGET=5.0
export PATH="/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/usr/bin:/Applications/Xcode.app/Contents/Developer/usr/bin:/usr/local/bin:/usr/bin:/bin:/usr/sbin:/sbin"
/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/libtool -static -arch_only armv7 -syslibroot /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS9.3.sdk -L/Users/appcell/Library/Developer/Xcode/DerivedData/elho-ctuevlyyxtyssvblxkqezbfgdtyq/Build/Intermediates/ArchiveIntermediates/Elho/BuildProductsPath/Release-iphoneos -filelist /Users/appcell/Library/Developer/Xcode/DerivedData/elho-ctuevlyyxtyssvblxkqezbfgdtyq/Build/Intermediates/ArchiveIntermediates/Elho/IntermediateBuildFilesPath/PSPDFKit-lib.build/Release-iphoneos/PSPDFKit.build/Objects-normal/armv7/PSPDFKit.LinkFileList /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS9.3.sdk/usr/lib/libz.dylib -framework AssetsLibrary -framework CoreMedia -framework AVFoundation -framework ImageIO -framework MediaPlayer -framework CoreText -framework CoreGraphics -weak_framework UIKit -framework MessageUI -framework QuartzCore -framework Foundation -o /Users/appcell/Library/Developer/Xcode/DerivedData/elho-ctuevlyyxtyssvblxkqezbfgdtyq/Build/Intermediates/ArchiveIntermediates/Elho/IntermediateBuildFilesPath/PSPDFKit-lib.build/Release-iphoneos/PSPDFKit.build/Objects-normal/armv7/libPSPDFKit.a

error: /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/libtool: can't open file: /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS9.3.sdk/usr/lib/libz.dylib (No such file or directory)

When I create a link frrom the /usr/lib/libz.dylib file to /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS9.3.sdk/usr/lib (which used to work in the past), I now get the following error:

ld: warning: ignoring file /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS9.3.sdk/usr/lib/libz.dylib, missing required architecture armv7 in file /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS9.3.sdk/usr/lib/libz.dylib (2 slices)
Undefined symbols for architecture armv7:
"_deflateInit_", referenced from:
  -[NSData(PSPDFCompression) pspdf_zlibDeflate] in libPSPDFKit.a(NSData+PSPDFCompression.o)
"_deflate", referenced from:
  -[ASIDataCompressor compressBytes:length:error:shouldFinish:] in ASIDataCompressor.o
  -[NSData(PSPDFCompression) pspdf_zlibDeflate] in libPSPDFKit.a(NSData+PSPDFCompression.o)
"_deflateInit2_", referenced from:
  -[ASIDataCompressor setupStream] in ASIDataCompressor.o
"_inflate", referenced from:
  _unzReadCurrentFile in unzip.o
  -[ASIDataDecompressor uncompressBytes:length:error:] in ASIDataDecompressor.o
  -[NSData(PSPDFCompression) pspdf_zlibInflate] in libPSPDFKit.a(NSData+PSPDFCompression.o)
"_get_crc_table", referenced from:
  _unzOpenCurrentFile3 in unzip.o
"_inflateEnd", referenced from:
  _unzCloseCurrentFile in unzip.o
  -[ASIDataDecompressor closeStream] in ASIDataDecompressor.o
  -[NSData(PSPDFCompression) pspdf_zlibInflate] in libPSPDFKit.a(NSData+PSPDFCompression.o)
"_crc32", referenced from:
  _unzReadCurrentFile in unzip.o
"_inflateInit_", referenced from:
  -[NSData(PSPDFCompression) pspdf_zlibInflate] in libPSPDFKit.a(NSData+PSPDFCompression.o)
"_deflateEnd", referenced from:
  -[ASIDataCompressor closeStream] in ASIDataCompressor.o
  -[NSData(PSPDFCompression) pspdf_zlibDeflate] in libPSPDFKit.a(NSData+PSPDFCompression.o)
"_inflateInit2_", referenced from:
  _unzOpenCurrentFile3 in unzip.o
  -[ASIDataDecompressor setupStream] in ASIDataDecompressor.o
ld: symbol(s) not found for architecture armv7
clang: error: linker command failed with exit code 1 (use -v to see invocation)

Has anyone ever had the same issues?

Answer 1

PSPDFKit founder here. Our PDF SDK uses libz, so either link with libz.dylib (which has been renamed in later Xcode versions to be libz.tbd) or add the linker flag -lz which should als do the trick.

If you update our SDK to the latest version this all happens automatically, since we're using a dynamic framework which already knows what dependencies it requires.