Thanks again, for now, setCallback() is only being called once...

but it still panics on the second callback, whether to the same callback as the first successful one, or a different one being called for the first time?

That it works the first time and fails the second, still makes me think I am messing up the stack somehow?

As you'll see below, I've had various attempts at ensuring that the stack is cleaned up. I've tried both the Inline_* macros and the XS macros to no avail?

#! perl -slw
use strict;
use Inline 'NoClean', 'FORCE', 'INFO' ;
use Inline Config => WARNINGS => 4;
use Inline 'C' => 'DATA', NAME =>'test';
use Devel::Peek;


sub recorder{ print "record: @_"; }
sub player{ print "player: @_"; }

print Dump \&recorder;

printf "r:%x p:%x\n", \&recorder, \&player;
setCallbacks( \&recorder, \&player );

record( 'test' );
play( 'test' );

__DATA__
__C__

SV *g_rec = (SV*)NULL;
SV *g_play = (SV*)NULL;

int setCallbacks( SV *rec, SV *play ) {
    printf( "r:%x p:%x\n", rec, play );
    g_rec  = SvREFCNT_inc( SvRV( rec ) );
    g_play = SvREFCNT_inc( SvRV( play ) );
    return 0;
}

int record( SV *m ) {
//    ENTER;
//    SAVETMPS;
    call_sv( g_rec, G_VOID );
//    FREETMPS;
//    LEAVE;
    return 0;
}

int play( SV *m ) {
//    ENTER;
//    SAVETMPS;
    call_sv( g_play, G_VOID );
//    FREETMPS;
//    LEAVE;
    return 0;
}
__END__
<-----------------------End of Information Section--------------------
+-------->
SV = RV(0x18404b4) at 0x1949a74
  REFCNT = 1
  FLAGS = (TEMP,ROK)
  RV = 0x226004
  SV = PVCV(0x1824094) at 0x226004
    REFCNT = 2
    FLAGS = ()
    IV = 0
    NV = 0
    COMP_STASH = 0x2251d0       "main"
    START = 0x1958cd4 ===> 11609
    ROOT = 0x1958c90
    XSUB = 0x0
    XSUBANY = 0
    GVGV::GV = 0x1959b98        "main" :: "recorder"
    FILE = "P:\test\test.pl"
    DEPTH = 0
    FLAGS = 0x0
    OUTSIDE_SEQ = 951
    PADLIST = 0x226010
    PADNAME = 0x22601c(0x1826a5c) PAD = 0x22604c(0x182ebb4)
    OUTSIDE = 0x2253c8 (MAIN)

r:226004 p:1959c04
r:1949a74 p:2252a8
record: test
panic: memory wrap at P:\test\test.pl line 18.
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