Determining if the include file pthread.h exists failed with the following output:
Change Dir: /home/autobuild/autobuild/instance-4/output-1/build/zxing-cpp-1.4.0/buildroot-build/CMakeFiles/CMakeTmp

Run Build Command(s):/home/autobuild/make/make -f Makefile cmTC_896a7/fast && make[1]: Entering directory '/home/autobuild/autobuild/instance-4/output-1/build/zxing-cpp-1.4.0/buildroot-build/CMakeFiles/CMakeTmp'
/home/autobuild/make/make  -f CMakeFiles/cmTC_896a7.dir/build.make CMakeFiles/cmTC_896a7.dir/build
make[2]: Entering directory '/home/autobuild/autobuild/instance-4/output-1/build/zxing-cpp-1.4.0/buildroot-build/CMakeFiles/CMakeTmp'
Building CXX object CMakeFiles/cmTC_896a7.dir/CheckIncludeFile.cxx.o
/home/autobuild/autobuild/instance-4/output-1/per-package/zxing-cpp/host/bin/xtensa-buildroot-linux-uclibc-g++ --sysroot=/home/autobuild/autobuild/instance-4/output-1/per-package/zxing-cpp/host/xtensa-buildroot-linux-uclibc/sysroot   -D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 -mlongcalls -mauto-litpools -O3 -g0   -DNDEBUG -std=c++17 -o CMakeFiles/cmTC_896a7.dir/CheckIncludeFile.cxx.o -c /home/autobuild/autobuild/instance-4/output-1/build/zxing-cpp-1.4.0/buildroot-build/CMakeFiles/CMakeTmp/CheckIncludeFile.cxx
/home/autobuild/autobuild/instance-4/output-1/build/zxing-cpp-1.4.0/buildroot-build/CMakeFiles/CMakeTmp/CheckIncludeFile.cxx:1:10: fatal error: pthread.h: No such file or directory
    1 | #include <pthread.h>
      |          ^~~~~~~~~~~
compilation terminated.
make[2]: *** [CMakeFiles/cmTC_896a7.dir/build.make:78: CMakeFiles/cmTC_896a7.dir/CheckIncludeFile.cxx.o] Error 1
make[2]: Leaving directory '/home/autobuild/autobuild/instance-4/output-1/build/zxing-cpp-1.4.0/buildroot-build/CMakeFiles/CMakeTmp'
make[1]: *** [Makefile:127: cmTC_896a7/fast] Error 2
make[1]: Leaving directory '/home/autobuild/autobuild/instance-4/output-1/build/zxing-cpp-1.4.0/buildroot-build/CMakeFiles/CMakeTmp'