Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Caret X does not use readlink() when coreutils are compiled with multicall support #15922

p5pRT opened this issue Mar 14, 2017 · 3 comments


Copy link

p5pRT commented Mar 14, 2017

Migrated from (status was 'open')

Searchable as RT130997$

Copy link

p5pRT commented Mar 14, 2017


Created by

When coreutils are compiled with multicall support, the command
ls -l /proc/self/exe outputs something like​:

  lrwxrwxrwx 1 user group 0 Jan 1 00​:00 /proc/self/exe -> /usr/bin/coreutils

But when determining the HAS_PROCSELFEXE macro, perl's Configure script
checks if the result of the ls command contains string '/ls'. It this case
this fails, because there is no /bin/ls, rather /usr/bin/coreutils.

Thus when perl is compiled on systems with multicall coreutils, it cannot
check the path to its own executable, and thus the $^X variable return argv[0].

I encountered this issue when compiling OpenWRT/LEDE on my Gentoo system with
multicall coreutils​: when perl is cross compiled, miniperl is just a symlink
to host's perl, which, in this case, is built to be relocatable. But the code
which searches for modules could not find the XXX/usr/lib/perl5 directory,
because instead of "XXX/usr/bin/perl", it had just "./miniperl" in $^X.

I think the best way to check for /proc/self/exe and similar symlinks in
Configure would be to compile a small test.c which check for this, ie. something

  #include <unistd.h>
  int main(int argc, char ** argv) {
  char r[1024];
  size_t l = readlink(argv[1], r, 1024);
  return l < 1024 && !strcmp(r, argv[2]));

Then Configure could just call /PATH/test /proc/self/exe /PATH/test to check
if /proc/self/exe works as intended.

Perl Info


Site configuration information for perl 5.24.1:

Configured by Gentoo at Fri Mar 10 18:00:40 CET 2017.

Summary of my perl5 (revision 5 version 24 subversion 1) configuration:
    osname=linux, osvers=4.9.13-gentoo, archname=x86_64-linux
    uname='linux thinkpad 4.9.13-gentoo #1 smp thu mar 9 11:43:35 cet 2017 x86_64 intel(r) core(tm) i7-3520m cpu @ 2.90ghz genuineintel gnulinux '
    config_args='-des -Dinstallprefix=/usr -Dinstallusrbinperl=n -Di_ndbm -Di_gdbm -Di_db -DDEBUGGING=none -Dinc_version_list=5.24.0/x86_64-linux 5.24.0  -Dlibpth=/usr/local/lib64 /lib64 /usr/lib64 -Dnoextensions=ODBM_File -Duseshrplib -Darchname=x86_64-linux -Dcc=x86_64-pc-linux-gnu-gcc -Doptimize=-march=native -O3 -pipe -fPIC -flto=4 -fuse-linker-plugin -Wl,-fuse-ld=gold -Dldflags=-Wl,-O1 -Wl,--as-needed -Dprefix=/usr -Dsiteprefix=/usr/local -Dvendorprefix=/usr -Dscriptdir=/usr/bin -Dprivlib=/usr/lib64/perl5/5.24.1 -Darchlib=/usr/lib64/perl5/5.24.1/x86_64-linux -Dsitelib=/usr/local/lib64/perl5/5.24.1 -Dsitearch=/usr/local/lib64/perl5/5.24.1/x86_64-linux -Dvendorlib=/usr/lib64/perl5/vendor_perl/5.24.1 -Dvendorarch=/usr/lib64/perl5/vendor_perl/5.24.1/x86_64-linux -Dman1dir=/usr/share/man/man1 -Dman3dir=/usr/share/man/man3 -Dsiteman1dir=/usr/local/man/man1 -Dsiteman3dir=/usr/local/man/man3 -Dvendorman1dir=/usr/share/man/man1 -Dvendorman3dir=/usr/share/man/man3 -Dman1ext=1
                 -Dman3ext=3pm -Dlocincpth=/usr/include  -Dglibpth=/lib64 /usr/lib64  -Duselargefiles -Dd_semctl_semun -Dcf_by=Gentoo -Dmyhostname=localhost -Dperladmin=root@localhost -Ud_csh -Dsh=/bin/sh -Dtargetsh=/bin/sh -Uusenm -Di_ndbm -Di_gdbm -Di_db -DDEBUGGING=none -Dinc_version_list=5.24.0/x86_64-linux 5.24.0  -Dlibpth=/usr/local/lib64 /lib64 /usr/lib64 -Dnoextensions=ODBM_File'
    hint=recommended, useposix=true, d_sigaction=define
    useithreads=undef, usemultiplicity=undef
    use64bitint=define, use64bitall=define, uselongdouble=undef
    usemymalloc=n, bincompat5005=undef
    cc='x86_64-pc-linux-gnu-gcc', ccflags ='-fwrapv -fno-strict-aliasing -pipe -D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64',
    optimize='-march=native -O3 -pipe -fPIC -flto=4 -fuse-linker-plugin -Wl,-fuse-ld=gold',
    cppflags='-fwrapv -fno-strict-aliasing -pipe'
    ccversion='', gccversion='5.4.0', 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='x86_64-pc-linux-gnu-gcc', ldflags ='-Wl,-O1 -Wl,--as-needed'
    libpth=/usr/local/lib64 /lib64 /usr/lib64 /usr/lib/gcc/x86_64-pc-linux-gnu/5.4.0/include-fixed /usr/lib /lib/../lib64 /usr/lib/../lib64 /lib
    libs=-lpthread -lnsl -lgdbm -ldb -ldl -lm -lcrypt -lutil -lc -lgdbm_compat
    perllibs=-lpthread -lnsl -ldl -lm -lcrypt -lutil -lc, so=so, useshrplib=true,
  Dynamic Linking:
    dlsrc=dl_dlopen.xs, dlext=so, d_dlsymun=undef, ccdlflags='-Wl,-E'
    cccdlflags='-fPIC', lddlflags='-shared -march=native -O3 -pipe -fPIC -flto=4 -fuse-linker-plugin -Wl,-fuse-ld=gold -Wl,-O1 -Wl,--as-needed'

Locally applied patches:
    gentoo/hints_hpux - Fix hpux hints
    gentoo/aix_soname - aix gcc detection and shared library soname support
    gentoo/EUMM-RUNPATH - cpan/ExtUtils-MakeMaker: drop $PORTAGE_TMPDIR from LD_RUN_PATH
    gentoo/config_over - Remove -rpath and append LDFLAGS to lddlflags
    gentoo/opensolaris_headers - Add headers for opensolaris
    gentoo/patchlevel - List packaged patches for perl-5.24.1-r1(#3) in patchlevel.h
    gentoo/cleanup-paths - Cleanup PATH and shrpenv
    gentoo/enc2xs - Tweak enc2xs to follow symlinks and ignore missing @INC directories.
    gentoo/darwin-cc-ld - darwin: Use $CC to link
    gentoo/cpan_definstalldirs - Provide a sensible INSTALLDIRS default for modules installed from CPAN.
    gentoo/interix - Fix interix hints
    gentoo/create_libperl_soname - Set libperl soname
    gentoo/mod_paths - Add /etc/perl to @INC
    gentoo/EUMM_perllocalpod - cpan/ExtUtils-MakeMaker: remove targets that generate perllocal.pod
    gentoo/drop_fstack_protector - Don't force -fstack-protector on everyone
    gentoo/usr_local - Configure: Don't include sources in /usr/local/ for compiling perl
    gentoo/D-SHA-CFLAGS - Do not set custom CFLAGS in cpan/Digest-SHA
    gentoo/io_socket_ip_tests - cpan/IO-Socket-IP: Disable network tests
    gentoo/cygwin-libperl - Cygwin: avoid libperl.dll.dll.a
    gentoo/tests - Fixup EUMM perlocal.pod tests and customised SHA1s
    gentoo/basepm-dot-inc - Protect against . in @INC
    gentoo/zlib-1.2.9-backported-fixes - [rt#119762] Compress-Raw-Zlib: backport zlib 1.2.9+ fixes from upstream 2.073
    gentoo/gcc6-lto-configure - [RT#128131] fix symbol detection with gcc 6 link-time optimization
    debian/cpan-missing-site-dirs - Fix CPAN::FirstTime defaults with nonexisting site dirs if a parent is writable
    debian/makemaker-pasthru - Pass LD settings through to subdirectories
    fixes/memoize_storable_nstore - [ #77790] Memoize::Storable: respect 'nstore' option not respected
    fixes/podman-pipe - Better errors for man pages from standard input
    fixes/respect_umask - Respect umask during installation
    fixes/net_smtp_docs - [ #36038] Document the Net::SMTP 'Port' option
    fixes/document_makemaker_ccflags - [ #68613] Document that CCFLAGS should include $Config{ccflags}
    fixes/parallel-manisort.patch - Fix parallel building

@INC for perl 5.24.1:

Environment for perl 5.24.1:
    LD_LIBRARY_PATH (unset)
    LOGDIR (unset)
    PERL_BADLANG (unset)

Copy link

p5pRT commented May 15, 2017

From @jkeenan

Are there any 'Configure' experts who could evaluate this bug report?

Thank you very much.

James E Keenan (jkeenan@​

Copy link

p5pRT commented May 15, 2017

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

Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
None yet

No branches or pull requests

2 participants