Makefile.PL fails with no '.' in @INC

[dcollinsn]

A recent security patch to Perl itself removed '.', the current working
directory, from @inc, the default search path for 'use', 'do', and
'require'. This fix for CVE-2016-1238 will be part of Perl 5.26.0, due
to be released this April, 2017. CPAN clients will temporarily
provide backwards compatibility during the module build/test process
by setting the environment variable PERL_USE_UNSAFE_INC=1 during build,
test, and install. HOWEVER:

1. This environment variable is a temporary fix only for compatibility,
   due to be removed for Perl 5.30.0.
2. This may mask errors in your module itself, by testing your module
   under different conditions than those that it will actually be run
   under.

To read more about this, you may find the following links helpful:

• http://blogs.perl.org/users/todd_rinaldo/2016/11/how-removing-from-inc-is-about-to-break-cpan.html
• https://www.perlmonks.org/?node_id=1186105
• http://www.nntp.perl.org/group/perl.perl5.porters/2017/03/msg243722.html

During a smoke-test of all of cpan, your distribution was found to be unable
to configure, build, test, or install without adding '.' to @inc. This means
that your distribution will stop building properly for all users when the
CPAN clients remove this temporary compatibility fix, and that it may
already have problems when used, problems which are being masked by this
temporary compatibility fix.

A full error log follows:

---

Output from '/home/cpan4/install/bin/perl Makefile.PL':

Can't locate inc/Module/Install.pm in @INC (you may need to install the inc::Module::Install module) (@INC contains: /tmp/CPAN-Reporter-lib-SX1f /home/cpan4/install/lib/perl5/site_perl/5.26.0/x86_64-linux-thread-multi /home/cpan4/install/lib/perl5/site_perl/5.26.0 /home/cpan4/install/lib/perl5/5.26.0/x86_64-linux-thread-multi /home/cpan4/install/lib/perl5/5.26.0) at Makefile.PL line 2.
BEGIN failed--compilation aborted at Makefile.PL line 2.

------------------------------
PREREQUISITES
------------------------------

Prerequisite modules loaded:

configure_requires:

    Module              Need Have
    ------------------- ---- ----
    ExtUtils::MakeMaker 6.59 7.24


------------------------------
ENVIRONMENT AND OTHER CONTEXT
------------------------------

Environment variables:

    AUTOMATED_TESTING = 1
    HARNESS_OPTIONS = j3
    LANG = en_US.UTF-8
    PATH = /usr/local/bin:/usr/bin:/bin:/usr/local/games:/usr/games
    PERL = /home/cpan4/install/bin/perl
    PERL5LIB = 
    PERL5OPT = -I/tmp/CPAN-Reporter-lib-SX1f -MDevel::Autoflush
    PERL5_CPANPLUS_IS_RUNNING = 6236
    PERL5_CPAN_IS_EXECUTING = /home/cpan4/.cpan/build/Text-MultiMarkdown-1.000035-0/Makefile.PL
    PERL5_CPAN_IS_RUNNING = 6236
    PERL5_CPAN_IS_RUNNING_IN_RECURSION = 23854,6236
    PERL_AUTOINSTALL = --defaultdeps
    PERL_CR_SMOKER_CURRENT = Text-MultiMarkdown-1.000035
    PERL_CR_SMOKER_RUNONCE = 1
    PERL_EXTUTILS_AUTOINSTALL = --defaultdeps
    PERL_MM_USE_DEFAULT = 1
    PERL_USE_UNSAFE_INC = 0
    SHELL = /bin/bash
    TERM = putty-256color

Perl special variables (and OS-specific diagnostics, for MSWin32):

    $^X = /home/cpan4/install/bin/perl
    $UID/$EUID = 1005 / 1005
    $GID = 1005 1005
    $EGID = 1005 1005

Perl module toolchain versions installed:

    Module              Have    
    ------------------- --------
    CPAN                2.16    
    CPAN::Meta          2.150010
    Cwd                 3.62    
    ExtUtils::CBuilder  0.280224
    ExtUtils::Command   7.24    
    ExtUtils::Install   2.04    
    ExtUtils::MakeMaker 7.24    
    ExtUtils::Manifest  1.70    
    ExtUtils::ParseXS   3.34    
    File::Spec          3.62    
    JSON                2.91_04 
    JSON::PP            2.27400 
    Module::Build       0.4222  
    Module::Signature   n/a     
    Parse::CPAN::Meta   2.150010
    Test::Harness       3.38    
    Test::More          1.302079
    YAML                1.23    
    YAML::Syck          1.29    
    version             0.9917  


--

Summary of my perl5 (revision 5 version 26 subversion 0) configuration:
  Commit id: 5fc389563644287b3e5f448616ce62dd0ce4e7a6
  Platform:
    osname=linux
    osvers=3.16.0-4-amd64
    archname=x86_64-linux-thread-multi
    uname='linux digitalis 3.16.0-4-amd64 #1 smp debian 3.16.36-1+deb8u2 (2016-10-19) x86_64 gnulinux '
    config_args='-Dusedevel -DDEBUGGING -Dusethreads -Dprefix=/home/cpan4/install -Uversiononly -des'
    hint=recommended
    useposix=true
    d_sigaction=define
    useithreads=define
    usemultiplicity=define
    use64bitint=define
    use64bitall=define
    uselongdouble=undef
    usemymalloc=n
    default_inc_excludes_dot=define
    bincompat5005=undef
  Compiler:
    cc='cc'
    ccflags ='-D_REENTRANT -D_GNU_SOURCE -fwrapv -DDEBUGGING -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 -g'
    cppflags='-D_REENTRANT -D_GNU_SOURCE -fwrapv -DDEBUGGING -fno-strict-aliasing -pipe -fstack-protector-strong -I/usr/local/include'
    ccversion=''
    gccversion='4.9.2'
    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/gcc/x86_64-linux-gnu/4.9/include-fixed /usr/include/x86_64-linux-gnu /usr/lib /lib/x86_64-linux-gnu /lib/../lib /usr/lib/x86_64-linux-gnu /usr/lib/../lib /lib /lib64 /usr/lib64
    libs=-lpthread -lnsl -ldl -lm -lcrypt -lutil -lc
    perllibs=-lpthread -lnsl -ldl -lm -lcrypt -lutil -lc
    libc=libc-2.19.so
    so=so
    useshrplib=false
    libperl=libperl.a
    gnulibc_version='2.19'
  Dynamic Linking:
    dlsrc=dl_dlopen.xs
    dlext=so
    d_dlsymun=undef
    ccdlflags='-Wl,-E'
    cccdlflags='-fPIC'
    lddlflags='-shared -O2 -g -L/usr/local/lib -fstack-protector-strong'


Characteristics of this binary (from libperl): 
  Compile-time options:
    DEBUGGING
    HAS_TIMES
    MULTIPLICITY
    PERLIO_LAYERS
    PERL_COPY_ON_WRITE
    PERL_DONT_CREATE_GVSV
    PERL_IMPLICIT_CONTEXT
    PERL_MALLOC_WRAP
    PERL_OP_PARENT
    PERL_PRESERVE_IVUV
    PERL_TRACK_MEMPOOL
    PERL_USE_DEVEL
    USE_64_BIT_ALL
    USE_64_BIT_INT
    USE_ITHREADS
    USE_LARGE_FILES
    USE_LOCALE
    USE_LOCALE_COLLATE
    USE_LOCALE_CTYPE
    USE_LOCALE_NUMERIC
    USE_LOCALE_TIME
    USE_PERLIO
    USE_PERL_ATOF
    USE_REENTRANT_API
  Built under linux
  Compiled at Apr  4 2017 17:17:49
  %ENV:
    PERL="/home/cpan4/install/bin/perl"
    PERL5LIB=""
    PERL5OPT=""
    PERL5_CPANPLUS_IS_RUNNING="6236"
    PERL5_CPAN_IS_EXECUTING="/home/cpan4/.cpan/build/Text-MultiMarkdown-1.000035-0/Makefile.PL"
    PERL5_CPAN_IS_RUNNING="6236"
    PERL5_CPAN_IS_RUNNING_IN_RECURSION="23854,6236"
    PERL_AUTOINSTALL="--defaultdeps"
    PERL_CR_SMOKER_CURRENT="Text-MultiMarkdown-1.000035"
    PERL_CR_SMOKER_RUNONCE="1"
    PERL_EXTUTILS_AUTOINSTALL="--defaultdeps"
    PERL_MM_USE_DEFAULT="1"
    PERL_USE_UNSAFE_INC="0"
  @INC:
    /home/cpan4/install/lib/perl5/site_perl/5.26.0/x86_64-linux-thread-multi
    /home/cpan4/install/lib/perl5/site_perl/5.26.0
    /home/cpan4/install/lib/perl5/5.26.0/x86_64-linux-thread-multi
    /home/cpan4/install/lib/perl5/5.26.0

[toddr]

Looks like #270 fixes things. Will there be a release soon?

[briandfoy]

I'm maintaining the module now and I've removed the Module::Install stuff. This shouldn't be a problem in 1.001, which I've just uploaded.