BBC: Blead Breaks B::Utils1

[cjg-cguevara]

This is a bug report for perl from "Carlos Guevara" [email protected],
generated with the help of perlbug 1.43 running under perl 5.41.7.

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BBC: Blead Breaks B::Utils1

Please see http://fast-matrix.cpantesters.org/?dist=B::Utils1

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Flags

• category=core
• severity=low

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Perl configuration

Site configuration information for perl 5.41.7:

Configured by cpan at Thu Dec 19 00:23:29 EST 2024.

Summary of my perl5 (revision 5 version 41 subversion 7) configuration:
  Commit id: 7496ff12fc1a5176641e424139fc7ad8e8ca08e5
  Platform:
    osname=linux
    osvers=5.14.0-503.16.1.el9_5.x86_64
    archname=x86_64-linux
    uname='linux cjg-rhel9 5.14.0-503.16.1.el9_5.x86_64 #1 smp preempt_dynamic thu nov 21 07:26:21 est 2024 x86_64 x86_64 x86_64 gnulinux '
    config_args='-des -Dprefix=/home/cpan/bin/perl -Dscriptdir=/home/cpan/bin/perl/bin -Dusedevel -Duse64bitall'
    hint=recommended
    useposix=true
    d_sigaction=define
    useithreads=undef
    usemultiplicity=undef
    use64bitint=define
    use64bitall=define
    uselongdouble=undef
    usemymalloc=n
    default_inc_excludes_dot=define
  Compiler:
    cc='cc'
    ccflags ='-fwrapv -fno-strict-aliasing -pipe -fstack-protector-strong -I/usr/local/include -D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64 -D_FORTIFY_SOURCE=2'
    optimize='-O2'
    cppflags='-fwrapv -fno-strict-aliasing -pipe -fstack-protector-strong -I/usr/local/include'
    ccversion=''
    gccversion='11.5.0 20240719 (Red Hat 11.5.0-2)'
    gccosandvers=''
    intsize=4
    longsize=8
    ptrsize=8
    doublesize=8
    byteorder=12345678
    doublekind=3
    d_longlong=define
    longlongsize=8
    d_longdbl=define
    longdblsize=16
    longdblkind=3
    ivtype='long'
    ivsize=8
    nvtype='double'
    nvsize=8
    Off_t='off_t'
    lseeksize=8
    alignbytes=8
    prototype=define
  Linker and Libraries:
    ld='cc'
    ldflags =' -fstack-protector-strong -L/usr/local/lib'
    libpth=/usr/local/lib /usr/lib /usr/lib64 /usr/local/lib64
    libs=-lpthread -ldb -ldl -lm -lcrypt -lutil -lc
    perllibs=-lpthread -ldl -lm -lcrypt -lutil -lc
    libc=/lib/../lib64/libc.so.6
    so=so
    useshrplib=false
    libperl=libperl.a
    gnulibc_version='2.34'
  Dynamic Linking:
    dlsrc=dl_dlopen.xs
    dlext=so
    d_dlsymun=undef
    ccdlflags='-Wl,-E'
    cccdlflags='-fPIC'
    lddlflags='-shared -O2 -L/usr/local/lib -fstack-protector-strong'


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@INC for perl 5.41.7:
    /home/cpan/bin/perl/lib/site_perl/5.41.7/x86_64-linux
    /home/cpan/bin/perl/lib/site_perl/5.41.7
    /home/cpan/bin/perl/lib/5.41.7/x86_64-linux
    /home/cpan/bin/perl/lib/5.41.7

---
Environment for perl 5.41.7:
    HOME=/home/cpan
    LANG=en_US.UTF-8
    LANGUAGE (unset)
    LC_ALL=C
    LD_LIBRARY_PATH (unset)
    LOGDIR (unset)
    PATH=/home/cpan/bin/perl/bin:/home/cpan/bin:/usr/share/Modules/bin:/usr/local/bin:/usr/bin:/usr/local/sbin:/usr/sbin
    PERL_BADLANG (unset)
    SHELL=/bin/bash

[jkeenan]

Bisecting with the following invocation:

perl Porting/bisect.pl \
--start=6f836886eca09c5df3a9f985231636e29b8f10dc \
--end=7496ff12fc1a5176641e424139fc7ad8e8ca08e5 \
--module=B::Utils1

... pointed to this as the breaking point:

7015de19863573066cc75ff79721681082895466 is the first bad commit
commit 7015de19863573066cc75ff79721681082895466
Author: Richard Leach <[email protected]>
Date:   Wed Nov 13 21:47:35 2024 +0000
Commit:     Richard Leach <[email protected]>
CommitDate: Mon Dec 16 21:32:16 2024 +0000

    op_scope/newCONDOP: Optimise away empty else blocks in OP_COND_EXPR

(Same commit as in GH #22866.)

@richardleach, can you take a look? Thanks.

[richardleach]

I'm initially working on the assumption that B::Utils and B::Utils1 have a common code ancestor and whatever fixes #22866 will likely also fix this issue. (Or it's a bug in 7015de1.)

[richardleach]

7015de1 reverted by 321290a. The need exists for a ternary to meaningfully push PL_sv_undef to the stack, whereas for an else {} block it doesn't matter.