Is it safe to use ax_gcc_builtin to detect __builtin_offsetof?

[Jeffrey Walton]

Hi Everyone,

The page <https://www.gnu.org/software/autoconf-archive/ax_gcc_builtin.html>
does not list __builtin_offsetof in the list of documented builtins.
But the page says "Unsupported built-ins will be tested with an empty
parameter set and the result of the check might be wrong or
meaningless so use with care."

Is it safe to use ax_gcc_builtin to detect __builtin_offsetof?

Sorry to ask. Google is not returning useful results.

Thanks in advance.