can't build boys.gpu.test - undefined reference to `main'

[jeffhammond]

I don't really know where to start with this...

jhammond@nuclear:~/Chemistry/libintx/build$ cmake --build .  --target boys.gpu.test
[ 66%] Built target libboys
[100%] Linking CXX executable boys.gpu.test
/usr/bin/ld: /usr/lib/gcc/x86_64-linux-gnu/11/../../../x86_64-linux-gnu/Scrt1.o: in function `_start':
(.text+0x1b): undefined reference to `main'
collect2: error: ld returned 1 exit status
gmake[3]: *** [tests/CMakeFiles/boys.gpu.test.dir/build.make:82: tests/boys.gpu.test] Error 1
gmake[2]: *** [CMakeFiles/Makefile2:1069: tests/CMakeFiles/boys.gpu.test.dir/all] Error 2
gmake[1]: *** [CMakeFiles/Makefile2:1076: tests/CMakeFiles/boys.gpu.test.dir/rule] Error 2
gmake: *** [Makefile:621: boys.gpu.test] Error 2