You are viewing the version of this documentation from Perl 5.33.2. This is a development release of Perl.
$COMPILING
$^C

The current value of the flag associated with the -c switch. Mainly of use with -MO=... to allow code to alter its behavior when being compiled, such as for example to AUTOLOAD at compile time rather than normal, deferred loading. Setting $^C = 1 is similar to calling B::minus_c.

This variable was added in Perl v5.6.0.