This is something that changed with 70f1346b: our libxamarin.dylib now
requires iOS 8+, which means the app itself must require iOS 8+ when using
libxamarin.dylib.
This fixes an msbuild failure (Xamarin.iOS.Tasks.IBToolLinking("iPhone").BuildTest):
Process exited with code 1, command:
/Applications/Xcode73.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/clang -framework Foundation -framework UIKit /Users/builder/data/lanes/1381/5f73edaa/source/xamarin-macios/_ios-build/Library/Frameworks/Xamarin.iOS.framework/Versions/git/SDKs/MonoTouch.iphoneos.sdk/usr/lib/libmonosgen-2.0.dylib /Users/builder/data/lanes/1381/5f73edaa/source/xamarin-macios/_ios-build/Library/Frameworks/Xamarin.iOS.framework/Versions/git/SDKs/MonoTouch.iphoneos.sdk/usr/lib/libxamarin-debug.dylib -lz -isysroot /Applications/Xcode73.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS9.3.sdk -Qunused-arguments -miphoneos-version-min=7.0 -arch armv7 -shared -read_only_relocs suppress -install_name @executable_path/libXamarin.iOS.dll.dylib -fapplication-extension -o /Users/builder/data/lanes/1381/5f73edaa/source/xamarin-macios/msbuild/tests/MyIBToolLinkTest/obj/iPhone/Debug/mtouch-cache/Xamarin.iOS.dll.armv7.dylib -x assembler /Users/builder/data/lanes/1381/5f73edaa/source/xamarin-macios/msbuild/tests/MyIBToolLinkTest/obj/iPhone/Debug/mtouch-cache/Xamarin.iOS.dll.armv7.s -DDEBUG
ld: warning: embedded dylibs/frameworks only run on iOS 8 or later
ld: embedded dylibs/frameworks are only supported on iOS 8.0 and later (@executable_path/libxamarin-debug.dylib) for architecture armv7
clang: error: linker command failed with exit code 1 (use -v to see invocation)
We need to compile the generated P/Invoke wrappers to a dylib, and link the
dylib for the product assembly (Xamarin.WatchOS.dll) with the generated
P/Invoke wrappers.
Since there might be P/Invokes in any assembly, just link in the P/Invoke
wrapper dylib for every assembly.
https://bugzilla.xamarin.com/show_bug.cgi?id=44048
Rolf Bjarne Kvinge
Manuel de la Pena
Sebastien Pouliot