Out-of-source build failure

[jserv]

After applying fixes from #3, file libinterpose.dylib was build. However, out-of-source build still fails. Re-run with make VERBOSE=1:

[ 18%] Built target syscall_tabgen
/Library/Developer/CommandLineTools/usr/bin/make  -f tests/CMakeFiles/file-O0.dir/build.make tests/CMakeFiles/file-O0.dir/depend
cd /tmp/86x64/build && /usr/local/Cellar/cmake/3.24.2/bin/cmake -E cmake_depends "Unix Makefiles" /tmp/86x64 /tmp/86x64/tests /tmp/86x64/build /tmp/86x64/build/tests /tmp/86x64/build/tests/CMakeFiles/file-O0.dir/DependInfo.cmake --color=
/Library/Developer/CommandLineTools/usr/bin/make  -f tests/CMakeFiles/file-O0.dir/build.make tests/CMakeFiles/file-O0.dir/build
[ 18%] Generating file-O0-32.o
cd /tmp/86x64/build/tests && cc -O0 -fno-stack-protector -fno-stack-check -c -m32 -o file-O0-32.o file.c
clang: error: no such file or directory: 'file.c'
clang: error: no input files
make[2]: *** [tests/file-O0-32.o] Error 1
make[1]: *** [tests/CMakeFiles/file-O0.dir/all] Error 2

It seems that build scripts attempted to search test files in directory build instead of directory tests in top-level.