3.16.0 FTBFS on osx: error: 'shared_mutex' is unavailable: introduced in macOS 10.12
We're trying to update to 3.16.0 in conda-forge with (seems we use osx 10.9), and it fails:
2019-11-30T11:41:10.9641780Z [ 78%] Building CXX object Source/CMakeFiles/CMakeServerLib.dir/cmConnection.cxx.o
2019-11-30T11:41:10.9646090Z cd $SRC_DIR/Source && $BUILD_PREFIX/bin/x86_64-apple-darwin13.4.0-clang++ -DLIBARCHIVE_STATIC -I$SRC_DIR/Utilities -I$SRC_DIR/Source -I$SRC_DIR/Source/LexerParser -I/Library/Frameworks/Mono.framework/Headers -I$SRC_DIR/Source/CTest -I$SRC_DIR/Source/CPack -isystem $SRC_DIR/Utilities/std -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 $PREFIX/include -fdebug-prefix-map=$SRC_DIR=/usr/local/src/conda/cmake-3.16.0 -fdebug-prefix-map=$PREFIX=/usr/local/src/conda-prefix -O3 -DNDEBUG -isysroot /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.9.sdk -mmacosx-version-min=10.9 -std=gnu++17 -o CMakeFiles/CMakeServerLib.dir/cmConnection.cxx.o -c $SRC_DIR/Source/cmConnection.cxx
2019-11-30T11:41:11.0979620Z Scanning dependencies of target CTestLib
2019-11-30T11:41:11.0989150Z make[2]: Leaving directory '$SRC_DIR'
2019-11-30T11:41:11.0990980Z make -f Source/CMakeFiles/CTestLib.dir/build.make Source/CMakeFiles/CTestLib.dir/build
2019-11-30T11:41:11.1151760Z make[2]: Entering directory '$SRC_DIR'
2019-11-30T11:41:11.1289100Z [ 79%] Building CXX object Source/CMakeFiles/CTestLib.dir/cmCTest.cxx.o
2019-11-30T11:41:11.1292560Z cd $SRC_DIR/Source && $BUILD_PREFIX/bin/x86_64-apple-darwin13.4.0-clang++ -DLIBARCHIVE_STATIC -I$SRC_DIR/Utilities -I$SRC_DIR/Source -I$SRC_DIR/Source/LexerParser -I/Library/Frameworks/Mono.framework/Headers -I$SRC_DIR/Source/CTest -I$SRC_DIR/Source/CPack -isystem $SRC_DIR/Utilities/std -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 $PREFIX/include -fdebug-prefix-map=$SRC_DIR=/usr/local/src/conda/cmake-3.16.0 -fdebug-prefix-map=$PREFIX=/usr/local/src/conda-prefix -O3 -DNDEBUG -isysroot /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.9.sdk -mmacosx-version-min=10.9 -std=gnu++17 -o CMakeFiles/CTestLib.dir/cmCTest.cxx.o -c $SRC_DIR/Source/cmCTest.cxx
2019-11-30T11:41:12.1183390Z In file included from /usr/local/miniconda/conda-bld/cmake_1575112968133/work/Source/cmConnection.cxx:10:
2019-11-30T11:41:12.1184840Z /usr/local/miniconda/conda-bld/cmake_1575112968133/work/Source/cmServer.h:68:15: error: 'shared_mutex' is unavailable: introduced in macOS 10.12
2019-11-30T11:41:12.1185320Z mutable cm::shared_mutex ConnectionsMutex;