I.e. preprocessor mode. This silences warning messages both when
cross-compiling perl and when compiling perl packages on device.
Note that the main perl binary ends up with RUNPATH set to
$PREFIX/lib/perl5/5.32.1/arm-android/CORE, instead of $PREFIX/lib
_and_ $PREFIX/lib/perl5/5.32.1/arm-android/CORE. perl only links
against the standard libraries and libperl.so though, and the latter
is in $PREFIX/lib/perl5/5.32.1/arm-android/CORE so there should be no
need to add $PREFIX/lib to RUNPATH (unless I am missing something).
Tested by running perl and installing some perl modules on an arm
tablet,
c7443b67fe