I get the error on 5.12.2 and 5.12.3. Didn't checking blead. The scalar in question is this one

$fh = IV(0x933914c) at 0x9339150
  REFCNT = 1
  FLAGS = (PADMY,ROK)
  RV = 0x938abe8
  SV = PVGV(0x9361de8) at 0x938abe8       <--------
    REFCNT = 3
    FLAGS = ()
    NAME = "$fh"
    NAMELEN = 3
    GvSTASH = 0x924ce18 "File::Temp"
    GP = 0x923d880
      SV = 0x0
      REFCNT = 1
      IO = 0x922ae48
      FORM = 0x0  
      AV = 0x0
      HV = 0x0
      CV = 0x0
      CVGEN = 0x0
      LINE = 513
      FILE = "/home/eric/usr/perlbrew/perls/perl-5.12.2/lib/5.12.2/Fil
+e/Temp.pm"
      FLAGS = 0x0
      EGV = 0x938abe8   "$fh"
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Destroying the tied handle before global destruction appears to avoid the problem.

{
   my $fhWrapper = Symbol::gensym;
   tie(local *$fhWrapper, 'MyWrapper', $fhWrapper, $fh);
   ...
}
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