Conda compilation from source not compatible with macOS SDK in Xcode 13

[traversaro]

Since yesterday, the CI of conda on macos-latest failed with:

2021-12-14T02:36:03.7886020Z [159/1268] Building CXX object src/libYARP_os/src/CMakeFiles/YARP_os.dir/yarp/os/impl/macos/MacOSAPI.mm.o
2021-12-14T02:36:03.7985980Z FAILED: src/libYARP_os/src/CMakeFiles/YARP_os.dir/yarp/os/impl/macos/MacOSAPI.mm.o 
2021-12-14T02:36:03.8099100Z /Users/runner/miniconda3/envs/test/bin/x86_64-apple-darwin13.4.0-clang++ -DBUILDING_YARP -DYARP_HAS_ACE -DYARP_HAS_Libedit -DYARP_os_EXPORTS -D__ACE_INLINE__ -I/Users/runner/work/robotology-superbuild/robotology-superbuild/src/YARP/src/libYARP_os/src -I/Users/runner/work/robotology-superbuild/robotology-superbuild/src/YARP/src/libYARP_conf/src -I/Users/runner/work/robotology-superbuild/robotology-superbuild/build/src/YARP/src/libYARP_conf/src -isystem /Users/runner/work/robotology-superbuild/robotology-superbuild/src/YARP/extern/hmac/hmac -Wall -Wextra -Wsign-compare -Wpointer-arith -Winit-self -Wnon-virtual-dtor -Wcast-align -Wunused -Wvla -Wmissing-include-dirs -Wreorder -Wsizeof-pointer-memaccess -Woverloaded-virtual -Wtautological-undefined-compare -Wmismatched-new-delete -Wparentheses-equality -Wundef -Wredundant-decls -Wunknown-pragmas -Wunused-result -Wc++17-compat -Wc++2a-compat -Wheader-guard -Wignored-attributes -Wnewline-eof -Wdangling-else -Wgcc-compat -Wmicrosoft-exists -Wstatic-inline-explicit-instantiation -Wmisleading-indentation -Wtautological-compare -Winconsistent-missing-override -Wsuggest-override -Wnull-conversion  -Wno-unused-parameter  -Wdeprecated-declarations -march=core2 -mtune=haswell -mssse3 -ftree-vectorize -fPIC -fPIE -fstack-protector-strong -O2 -pipe -stdlib=libc++ -fvisibility-inlines-hidden -std=c++14 -fmessage-length=0 -isystem /Users/runner/miniconda3/envs/test/include -O3 -DNDEBUG -isysroot /Applications/Xcode_13.1.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX.sdk -fPIC -fvisibility=hidden -fvisibility-inlines-hidden -std=c++14 -MD -MT src/libYARP_os/src/CMakeFiles/YARP_os.dir/yarp/os/impl/macos/MacOSAPI.mm.o -MF src/libYARP_os/src/CMakeFiles/YARP_os.dir/yarp/os/impl/macos/MacOSAPI.mm.o.d -o src/libYARP_os/src/CMakeFiles/YARP_os.dir/yarp/os/impl/macos/MacOSAPI.mm.o -c /Users/runner/work/robotology-superbuild/robotology-superbuild/src/YARP/src/libYARP_os/src/yarp/os/impl/macos/MacOSAPI.mm
2021-12-14T02:36:03.8188790Z In file included from /Users/runner/work/robotology-superbuild/robotology-superbuild/src/YARP/src/libYARP_os/src/yarp/os/impl/macos/MacOSAPI.mm:8:
2021-12-14T02:36:03.8289100Z In file included from /Applications/Xcode_13.1.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX.sdk/System/Library/Frameworks/Foundation.framework/Headers/Foundation.h:12:
2021-12-14T02:36:03.8392380Z /Applications/Xcode_13.1.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX.sdk/System/Library/Frameworks/Foundation.framework/Headers/NSBundle.h:91:143: error: function does not return NSString
2021-12-14T02:36:03.8493800Z - (NSAttributedString *)localizedAttributedStringForKey:(NSString *)key value:(nullable NSString *)value table:(nullable NSString *)tableName NS_FORMAT_ARGUMENT(1) NS_REFINED_FOR_SWIFT API_AVAILABLE(macos(12.0), ios(15.0), watchos(8.0), tvos(15.0));
2021-12-14T02:36:03.8592390Z                                                          ~~~~~~~~~~~~~~                                                                       ^                  ~
2021-12-14T02:36:03.8695020Z /Applications/Xcode_13.1.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX.sdk/System/Library/Frameworks/Foundation.framework/Headers/NSObjCRuntime.h:103:48: note: expanded from macro 'NS_FORMAT_ARGUMENT'
2021-12-14T02:36:03.8794480Z         #define NS_FORMAT_ARGUMENT(A) __attribute__ ((format_arg(A)))
2021-12-14T02:36:03.8895780Z                                                       ^          ~
2021-12-14T02:36:03.8998840Z In file included from /Users/runner/work/robotology-superbuild/robotology-superbuild/src/YARP/src/libYARP_os/src/yarp/os/impl/macos/MacOSAPI.mm:8:
2021-12-14T02:36:03.9068890Z In file included from /Applications/Xcode_13.1.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX.sdk/System/Library/Frameworks/Foundation.framework/Headers/Foundation.h:130:
2021-12-14T02:36:03.9188110Z /Applications/Xcode_13.1.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX.sdk/System/Library/Frameworks/Foundation.framework/Headers/NSURLSession.h:500:168: error: expected ')'
2021-12-14T02:36:03.9292600Z - (void)readDataOfMinLength:(NSUInteger)minBytes maxLength:(NSUInteger)maxBytes timeout:(NSTimeInterval)timeout completionHandler:(void (^) (NSData * _Nullable_result data, BOOL atEOF, NSError * _Nullable error))completionHandler;
2021-12-14T02:36:03.9398600Z                                                                                                                                                                        ^
2021-12-14T02:36:03.9501760Z /Applications/Xcode_13.1.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX.sdk/System/Library/Frameworks/Foundation.framework/Headers/NSURLSession.h:500:141: note: to match this '('
2021-12-14T02:36:03.9603800Z - (void)readDataOfMinLength:(NSUInteger)minBytes maxLength:(NSUInteger)maxBytes timeout:(NSTimeInterval)timeout completionHandler:(void (^) (NSData * _Nullable_result data, BOOL atEOF, NSError * _Nullable error))completionHandler;
2021-12-14T02:36:03.9701700Z                                                                                                                                             ^
2021-12-14T02:36:03.9806730Z 2 errors generated.

Homebrew on macos-10.15 did not failed, so I wonder if this problem is related to the macos-latest image.

[traversaro]

So, conda compiler fail with the macOS SDK provided by XCode 13. As a cross-check, I added a CI run with homebrew with Xcode 13 in #960, to understand if that fails also there or not.

[traversaro]

As shown in #960, the homebrew CI works fine. The issue is caused by some kind of incompatibility between the macOS SDK in Xcode 13 and the conda-forge compilers.

[traversaro]

The problem was solved on its own, see #1216 , probably thanks to a compiler or macOS SDK update, a rare case in which ignoring a problem and just putting in place a workaround eventually lead to the problem being solved. : )