test.p6

use NativeCall;

sub cb(Pointer $, Str $) { say 42 }

sub tcc_new(--> Pointer) is native('libtcc') {*}
sub tcc_set_error_func(Pointer, Pointer, &cb (Pointer, Str))
    is native('libtcc') {*}

sub tcc_compile_string(Pointer, Str --> int32) is native('libtcc') {*}

my $tcc = tcc_new;
tcc_set_error_func($tcc, Nil, &cb);
tcc_compile_string($tcc, 'xxx');