Determining if the futimes exist failed with the following output: Change Dir: /home/buildroot/autobuild/instance-3/output-1/build/libdeflate-1.15/CMakeFiles/CMakeTmp Run Build Command(s):/usr/bin/make -f Makefile cmTC_6b918/fast && make[1]: Entering directory '/home/buildroot/autobuild/instance-3/output-1/build/libdeflate-1.15/CMakeFiles/CMakeTmp' /usr/bin/make -f CMakeFiles/cmTC_6b918.dir/build.make CMakeFiles/cmTC_6b918.dir/build make[2]: Entering directory '/home/buildroot/autobuild/instance-3/output-1/build/libdeflate-1.15/CMakeFiles/CMakeTmp' Building C object CMakeFiles/cmTC_6b918.dir/CheckSymbolExists.c.o /home/buildroot/autobuild/instance-3/output-1/host/bin/x86_64-buildroot-linux-uclibc-gcc --sysroot=/home/buildroot/autobuild/instance-3/output-1/host/x86_64-buildroot-linux-uclibc/sysroot -D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 -O2 -g0 -static -D_DEFAULT_SOURCE -DNDEBUG -o CMakeFiles/cmTC_6b918.dir/CheckSymbolExists.c.o -c /home/buildroot/autobuild/instance-3/output-1/build/libdeflate-1.15/CMakeFiles/CMakeTmp/CheckSymbolExists.c /home/buildroot/autobuild/instance-3/output-1/build/libdeflate-1.15/CMakeFiles/CMakeTmp/CheckSymbolExists.c: In function 'main': /home/buildroot/autobuild/instance-3/output-1/build/libdeflate-1.15/CMakeFiles/CMakeTmp/CheckSymbolExists.c:8:19: error: 'futimes' undeclared (first use in this function); did you mean 'lutimes'? 8 | return ((int*)(&futimes))[argc]; | ^~~~~~~ | lutimes /home/buildroot/autobuild/instance-3/output-1/build/libdeflate-1.15/CMakeFiles/CMakeTmp/CheckSymbolExists.c:8:19: note: each undeclared identifier is reported only once for each function it appears in CMakeFiles/cmTC_6b918.dir/build.make:77: recipe for target 'CMakeFiles/cmTC_6b918.dir/CheckSymbolExists.c.o' failed make[2]: *** [CMakeFiles/cmTC_6b918.dir/CheckSymbolExists.c.o] Error 1 make[2]: Leaving directory '/home/buildroot/autobuild/instance-3/output-1/build/libdeflate-1.15/CMakeFiles/CMakeTmp' Makefile:127: recipe for target 'cmTC_6b918/fast' failed make[1]: *** [cmTC_6b918/fast] Error 2 make[1]: Leaving directory '/home/buildroot/autobuild/instance-3/output-1/build/libdeflate-1.15/CMakeFiles/CMakeTmp' File /home/buildroot/autobuild/instance-3/output-1/build/libdeflate-1.15/CMakeFiles/CMakeTmp/CheckSymbolExists.c: /* */ #include int main(int argc, char** argv) { (void)argv; #ifndef futimes return ((int*)(&futimes))[argc]; #else (void)argc; return 0; #endif }