-Werror is redundant because CMake parses the output of try_compile, and if it finds the name of the tested flag in the output it concludes that the flag is unsupported. The patch also fixes a typo in a variable name that was the reason for adding -Werror in the first place.

-Werror is redundant because CMake not only checks the exit status, but also parses the output of try_compile. -Wformat-security is a special case, because specifying it without -Wformat causes gcc to emit a warning in a format not recognized by CMake, which makes the check pass.

-Werror is redundant because CMake parses the output of try_compile,not only checks the and if it finds the name of the tested flag inexit status, but also parses the output it concludesof try_compile. that the flag is unsupported.-Wformat-security is a special case, because specifying it The patch also fixes a typowithout -Wformat causes gcc to emit a warning in a variable name that waformat not recognized by CMake, which makes the reason forcheck pass. adding -Werror in the first place.