[ 93%] Building CXX object CMakeFiles/nana.dir/source/system/platform.cpp.o
/opt/local/bin/ccache /usr/bin/clang++ -DAPPLE -DNANA_IGNORE_CONF -I/opt/local/var/macports/build/nana-d07a3683/work/nana-1.7.4/include -isystem /opt/local/include -isystem /opt/local/include/freetype2 -pipe -Os -DNDEBUG -I/opt/local/include -stdlib=libc++ -isysroot/Library/Developer/CommandLineTools/SDKs/MacOSX10.15.sdk -std=gnu++17 -arch x86_64 -isysroot /Library/Developer/CommandLineTools/SDKs/MacOSX10.15.sdk -mmacosx-version-min=10.15 -Wall -MD -MT CMakeFiles/nana.dir/source/system/platform.cpp.o -MF CMakeFiles/nana.dir/source/system/platform.cpp.o.d -o CMakeFiles/nana.dir/source/system/platform.cpp.o -c /opt/local/var/macports/build/nana-d07a3683/work/nana-1.7.4/source/system/platform.cpp
/opt/local/var/macports/build/nana-d07a3683/work/nana-1.7.4/source/system/platform.cpp:89:7: error: use of undeclared identifier 'errno'
                        if(errno == EINTR)
                           ^
/opt/local/var/macports/build/nana-d07a3683/work/nana-1.7.4/source/system/platform.cpp:89:16: error: use of undeclared identifier 'EINTR'
                        if(errno == EINTR)
                                    ^
/opt/local/var/macports/build/nana-d07a3683/work/nana-1.7.4/source/system/platform.cpp:106:22: warning: 'syscall' is deprecated: first deprecated in macOS 10.12 - syscall(2) is unsupported; please switch to a supported interface. For SYS_kdebug_trace use kdebug_signpost(). [-Wdeprecated-declarations]
                return (thread_t)::syscall(SYS_thread_selfid);
                                   ^
/Library/Developer/CommandLineTools/SDKs/MacOSX10.15.sdk/usr/include/unistd.h:742:6: note: 'syscall' has been explicitly marked deprecated here
int      syscall(int, ...);
         ^
1 warning and 2 errors generated.