In file included from /usr/lib/arm-linux-gnueabihf/perl/5.20/CORE/perl.h:5102:0, from TellStick.xs:2: TellStick.xs: In function ‘XS_TellStick_tdSensor’: TellStick.xs:76:31: warning: passing argument 2 of ‘Perl_newRV_noinc’ from incompatible pointer type RETVAL = newRV_noinc(hv); ^ /usr/lib/arm-linux-gnueabihf/perl/5.20/CORE/embed.h:371:48: note: in definition of macro ‘newRV_noinc’ #define newRV_noinc(a) Perl_newRV_noinc(aTHX_ a) ^ In file included from /usr/lib/arm-linux-gnueabihf/perl/5.20/CORE/perl.h:5061:0, from TellStick.xs:2: /usr/lib/arm-linux-gnueabihf/perl/5.20/CORE/proto.h:2874:19: note: expected ‘struct SV * const’ but argument is of type ‘struct HV *’ PERL_CALLCONV SV* Perl_newRV_noinc(pTHX_ SV *const sv)