Without this all checks fail-Werror is redundant because CMake pasrses the flagsoutput of try_compile,
like this:and if it finds the name of the tested flag in the output it concludes
`... -nodefaultlibs -D-Warray-bounds -Werror -std=c++17 ...`that the flag is unsupported.
NotThe patch also fixes a typo in a variable name the `-D` beforeat was the reason for
adding -Werror in the `-W`first place.