Get-magic is ignored on retval of @INC hook

[p5pRT]

Migrated from rt.perl.org#105908 (status was 'resolved')

Searchable as RT105908$

[p5pRT]

From @cpansprout

sub TIESCALAR { bless \$_[0] }
sub FETCH { ${$_[0]} }
unshift @​INC, sub { tie $x, "", sub { warn "called"; $_ = 1; 0} };
require foo;

That program gives​:

foo.pm did not return a true value at - line 4.

I would expect​:

called at - line 3.

---

Flags​:
  category=core
  severity=low

---

Site configuration information for perl 5.15.4​:

Configured by sprout at Wed Nov 2 09​:06​:14 PDT 2011.

Summary of my perl5 (revision 5 version 15 subversion 4) configuration​:
  Snapshot of​: f364061
  Platform​:
  osname=darwin, osvers=10.5.0, archname=darwin-thread-multi-2level
  uname='darwin pint.local 10.5.0 darwin kernel version 10.5.0​: fri nov 5 23​:20​:39 pdt 2010; root​:xnu-1504.9.17~1release_i386 i386 '
  config_args='-de -Doptimize=-g -Dusedevel -Duseithreads -Dmad'
  hint=recommended, useposix=true, d_sigaction=define
  useithreads=define, usemultiplicity=define
  useperlio=define, d_sfio=undef, uselargefiles=define, usesocks=undef
  use64bitint=undef, use64bitall=undef, uselongdouble=undef
  usemymalloc=n, bincompat5005=undef
  Compiler​:
  cc='cc', ccflags ='-fno-common -DPERL_DARWIN -fno-strict-aliasing -pipe -fstack-protector -I/usr/local/include',
  optimize='-g',
  cppflags='-fno-common -DPERL_DARWIN -fno-strict-aliasing -pipe -fstack-protector -I/usr/local/include'
  ccversion='', gccversion='4.2.1 (Apple Inc. build 5664)', gccosandvers=''
  intsize=4, longsize=4, ptrsize=4, doublesize=8, byteorder=1234
  d_longlong=define, longlongsize=8, d_longdbl=define, longdblsize=16
  ivtype='long', ivsize=4, nvtype='double', nvsize=8, Off_t='off_t', lseeksize=8
  alignbytes=8, prototype=define
  Linker and Libraries​:
  ld='env MACOSX_DEPLOYMENT_TARGET=10.3 cc', ldflags =' -fstack-protector -L/usr/local/lib'
  libpth=/usr/local/lib /usr/lib
  libs=-ldbm -ldl -lm -lutil -lc
  perllibs=-ldl -lm -lutil -lc
  libc=, so=dylib, useshrplib=false, libperl=libperl.a
  gnulibc_version=''
  Dynamic Linking​:
  dlsrc=dl_dlopen.xs, dlext=bundle, d_dlsymun=undef, ccdlflags=' '
  cccdlflags=' ', lddlflags=' -bundle -undefined dynamic_lookup -L/usr/local/lib -fstack-protector'

Locally applied patches​:
 

---

@​INC for perl 5.15.4​:
  /usr/local/lib/perl5/site_perl/5.15.4/darwin-thread-multi-2level
  /usr/local/lib/perl5/site_perl/5.15.4
  /usr/local/lib/perl5/5.15.4/darwin-thread-multi-2level
  /usr/local/lib/perl5/5.15.4
  /usr/local/lib/perl5/site_perl
  .

---

Environment for perl 5.15.4​:
  DYLD_LIBRARY_PATH (unset)
  HOME=/Users/sprout
  LANG=en_US.UTF-8
  LANGUAGE (unset)
  LD_LIBRARY_PATH (unset)
  LOGDIR (unset)
  PATH=/usr/bin​:/bin​:/usr/sbin​:/sbin​:/usr/local/bin​:/usr/X11/bin​:/usr/local/bin
  PERL_BADLANG (unset)
  SHELL=/bin/bash

[p5pRT]

From zefram@fysh.org

The test case that you gave doesn't make sense; it seems to be a mishmash
of two different approaches to demonstrating the issue. Nevertheless,
it is correct that get magic wasn't applied there in 5.15.4. A test
case that makes sense is​:

$ perl5.15.4 -lwe 'sub TIESCALAR { my $z = $_[1]; bless \$z } sub FETCH { warn "fetched"; ${$_[0]} } unshift @​INC, sub { tie my $x, "main", "123"; \$x }; require foo'
foo.pm did not return a true value at -e line 1.

This apparently got fixed in 5.19.4, and now the test case passes​:

$ perl5.27.5 -lwe 'sub TIESCALAR { my $z = $_[1]; bless \$z } sub FETCH { warn "fetched"; ${$_[0]} } unshift @​INC, sub { tie my $x, "main", "123"; \$x }; require foo'
fetched at -e line 1.

This ticket can be closed.

-zefram

[p5pRT]

The RT System itself - Status changed from 'new' to 'open'

[p5pRT]

@xsawyerx - Status changed from 'open' to 'resolved'

[p5pRT]

From @cpansprout

On Sat, 04 Nov 2017 16​:05​:46 -0700, zefram fysh.org wrote​:

This apparently got fixed in 5.19.4, and now the test case passes​:

$ perl5.27.5 -lwe 'sub TIESCALAR { my $z = $_[1]; bless \$z } sub
FETCH { warn "fetched"; ${$_[0]} } unshift @​INC, sub { tie my $x,
"main", "123"; \$x }; require foo'
fetched at -e line 1.

This ticket can be closed.

-zefram

For the record, it seems I fixed it​:

commit 536ac39
Author​: Father Chrysostomos <sprout@​cpan.org>
Date​: Fri Aug 9 08​:42​:32 2013 -0700

  Tying $_ in @​INC filter
 
  Crazy? Probably. But the existing code partially handles magic val-
  ues already; it’s just buggy. Also, the magic value could come from
  another source filter that is not registered via @​INC, and this is one
  way to test that code path.

--

Father Chrysostomos

[p5pRT]

From [Unknown Contact. See original ticket]

On Sat, 04 Nov 2017 16​:05​:46 -0700, zefram fysh.org wrote​:

This apparently got fixed in 5.19.4, and now the test case passes​:

$ perl5.27.5 -lwe 'sub TIESCALAR { my $z = $_[1]; bless \$z } sub
FETCH { warn "fetched"; ${$_[0]} } unshift @​INC, sub { tie my $x,
"main", "123"; \$x }; require foo'
fetched at -e line 1.

This ticket can be closed.

-zefram

For the record, it seems I fixed it​:

commit 536ac39
Author​: Father Chrysostomos <sprout@​cpan.org>
Date​: Fri Aug 9 08​:42​:32 2013 -0700

  Tying $_ in @​INC filter
 
  Crazy? Probably. But the existing code partially handles magic val-
  ues already; it’s just buggy. Also, the magic value could come from
  another source filter that is not registered via @​INC, and this is one
  way to test that code path.

--

Father Chrysostomos

[p5pRT]

From @cpansprout

On Wed, 15 Nov 2017 12​:56​:42 -0800, sprout wrote​:

On Sat, 04 Nov 2017 16​:05​:46 -0700, zefram fysh.org wrote​:

This apparently got fixed in 5.19.4, and now the test case passes​:

$ perl5.27.5 -lwe 'sub TIESCALAR { my $z = $_[1]; bless \$z } sub
FETCH { warn "fetched"; ${$_[0]} } unshift @​INC, sub { tie my $x,
"main", "123"; \$x }; require foo'
fetched at -e line 1.

This ticket can be closed.

-zefram

For the record, it seems I fixed it​:

commit 536ac39
Author​: Father Chrysostomos <sprout@​cpan.org>
Date​: Fri Aug 9 08​:42​:32 2013 -0700

Tying $\_ in @​INC filter

Sorry, wrong commit but same branch. This is it​:

commit 2e8409a
Author​: Father Chrysostomos <sprout@​cpan.org>
Date​: Fri Aug 9 13​:32​:30 2013 -0700

  Handle magical return values from @​INC filter
 
  An @​INC filter (a subroutined returned by a subroutine in @​INC) could
  be an lvalue sub that returns a magical scalar for the status. We
  need to account for that.
 
  If we don’t call get-magic (FETCH), we’ll get the last value assigned
  to or returned from that scalar.

--

Father Chrysostomos

[p5pRT]

From [Unknown Contact. See original ticket]

On Wed, 15 Nov 2017 12​:56​:42 -0800, sprout wrote​:

On Sat, 04 Nov 2017 16​:05​:46 -0700, zefram fysh.org wrote​:

This apparently got fixed in 5.19.4, and now the test case passes​:

$ perl5.27.5 -lwe 'sub TIESCALAR { my $z = $_[1]; bless \$z } sub
FETCH { warn "fetched"; ${$_[0]} } unshift @​INC, sub { tie my $x,
"main", "123"; \$x }; require foo'
fetched at -e line 1.

This ticket can be closed.

-zefram

For the record, it seems I fixed it​:

commit 536ac39
Author​: Father Chrysostomos <sprout@​cpan.org>
Date​: Fri Aug 9 08​:42​:32 2013 -0700

Tying $\_ in @​INC filter

Sorry, wrong commit but same branch. This is it​:

commit 2e8409a
Author​: Father Chrysostomos <sprout@​cpan.org>
Date​: Fri Aug 9 13​:32​:30 2013 -0700

  Handle magical return values from @​INC filter
 
  An @​INC filter (a subroutined returned by a subroutine in @​INC) could
  be an lvalue sub that returns a magical scalar for the status. We
  need to account for that.
 
  If we don’t call get-magic (FETCH), we’ll get the last value assigned
  to or returned from that scalar.

--

Father Chrysostomos