#! perl -slw
use strict;

use Inline C => << '__C__', NAME => 'test', CLEAN_AFTER_BUILD => 0;
#include <stdio.h>

SV* test( SV *a, SV *b ) {
  SV * n = newSVsv( a );
 
    if( !SvPOK( n ) && ( SvNOK( n ) || SvIOK( n ) || SvUOK( n ) ) ) // numeric
        SvPV_nolen( n );             // Force a string rep

    if( !SvPOK( n ) )      // Still nothing, must be undef?
        sv_setpv( n, "" ); // Make it the null string to stop (one possible)
        // Use of uninitialized value in subroutine entry from sv_catsv

    
    if(SvPOK( b ) || ( !SvPOK( b ) && ( SvNOK( b ) || SvIOK( b ) || SvUOK( b ) ) ) ){
      sv_catsv( n, b );
    }
    return n;
}

__C__

print test( 'bill', 'fred' );

my( $p, $q ) = ( 'fred' );
print test( $q, $p );

$q = 'bill';
print test( $q, $p );

$q = 1;
print test( $q, $p );

$p = 1;
print test( $q, $p );
__OUTPUT__
billfred
fred
billfred
1fred
11