Determining if the include file pthread.h exists failed with the following output:
Change Dir: /home/buildroot/autobuild/instance-3/output-1/build/libuhttpd-3.14.1/CMakeFiles/CMakeTmp

Run Build Command(s):/usr/bin/gmake -f Makefile cmTC_35314/fast && gmake[1]: Entering directory '/home/buildroot/autobuild/instance-3/output-1/build/libuhttpd-3.14.1/CMakeFiles/CMakeTmp'
/usr/bin/gmake  -f CMakeFiles/cmTC_35314.dir/build.make CMakeFiles/cmTC_35314.dir/build
gmake[2]: Entering directory '/home/buildroot/autobuild/instance-3/output-1/build/libuhttpd-3.14.1/CMakeFiles/CMakeTmp'
Building C object CMakeFiles/cmTC_35314.dir/CheckIncludeFile.c.o
/home/buildroot/autobuild/instance-3/output-1/host/bin/mips64-buildroot-linux-uclibc-gcc --sysroot=/home/buildroot/autobuild/instance-3/output-1/host/mips64-buildroot-linux-uclibc/sysroot   -D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 -Og -g0 -static  -o CMakeFiles/cmTC_35314.dir/CheckIncludeFile.c.o -c /home/buildroot/autobuild/instance-3/output-1/build/libuhttpd-3.14.1/CMakeFiles/CMakeTmp/CheckIncludeFile.c
/home/buildroot/autobuild/instance-3/output-1/build/libuhttpd-3.14.1/CMakeFiles/CMakeTmp/CheckIncludeFile.c:1:10: fatal error: pthread.h: No such file or directory
    1 | #include <pthread.h>
      |          ^~~~~~~~~~~
compilation terminated.
gmake[2]: *** [CMakeFiles/cmTC_35314.dir/build.make:78: CMakeFiles/cmTC_35314.dir/CheckIncludeFile.c.o] Error 1
gmake[2]: Leaving directory '/home/buildroot/autobuild/instance-3/output-1/build/libuhttpd-3.14.1/CMakeFiles/CMakeTmp'
gmake[1]: *** [Makefile:127: cmTC_35314/fast] Error 2
gmake[1]: Leaving directory '/home/buildroot/autobuild/instance-3/output-1/build/libuhttpd-3.14.1/CMakeFiles/CMakeTmp'