草莓Perl警告子程序Config：：存储从perl库重新定义？

Question

我正在维护一些Perl脚本，最近我注意到其中许多脚本输出了来自“系统”的Subroutine ... redefined警告，而不是我们编写的任何代码。

我现在可以举出的一个简化的例子是：

#!perl -W

use strict;
use warnings;
use 5.14.0;

# These work without warnings:
use Carp;
use URI;
use POSIX;

# Any of these will generate warnings:
# use LWP; # Subroutine Config::STORE redefined at C:/local/Perl-5.32.1-64bit-portable/perl/vendor/lib/Portable/Config.pm line 68.
# use XML::LibXML; # Subroutine Config::STORE redefined at C:/local/Perl-5.32.1-64bit-portable/perl/vendor/lib/Portable/Config.pm line 68.
# use Win32::Service; # Subroutine Win32::GetCwd redefined at C:/local/Perl-5.32.1-64bit-portable/perl/lib/DynaLoader.pm line 210. (and 20!! more)
# ...

say "Hello world.";

在Windows10上使用Strawberry Perl 5.32.1 x64 ZIP/Portable，也用草莓5.14进行测试。通过portableshell.bat -> perl testscript.pl运行

我觉得奇怪的是，这么多的“系统”模块会生成这些警告，尤其是因为我还不记得几个月前我做一些维护工作时看到过这些警告。

• ，我是不是应该压制一下这些警告？
• 还有什么可以检查的吗？

C:\local\Perl-5.32.1-64bit-portable>perl -V
Summary of my perl5 (revision 5 version 32 subversion 1) configuration:

  Platform:
    osname=MSWin32
    osvers=10.0.19042.746
    archname=MSWin32-x64-multi-thread
    uname='Win32 strawberry-perl 5.32.1.1 #1 Sun Jan 24 15:00:15 2021 x64'
    config_args='undef'
    hint=recommended
    useposix=true
    d_sigaction=undef
    useithreads=define
    usemultiplicity=define
    use64bitint=define
    use64bitall=undef
    uselongdouble=undef
    usemymalloc=n
    default_inc_excludes_dot=define
    bincompat5005=undef
  Compiler:
    cc='gcc'
    ccflags =' -DWIN32 -DWIN64 -D__USE_MINGW_ANSI_STDIO -DPERL_TEXTMODE_SCRIPTS -DPERL_IMPLICIT_CONTEXT -DPERL_IMPLICIT_SYS -DUSE_PERLIO -fwrapv -fno-strict-aliasing -mms-bitfields'
    optimize='-s -O2'
    cppflags='-DWIN32'
    ccversion=''
    gccversion='8.3.0'
    gccosandvers=''
    intsize=4
    longsize=4
    ptrsize=8
    doublesize=8
    byteorder=12345678
    doublekind=3
    d_longlong=define
    longlongsize=8
    d_longdbl=define
    longdblsize=16
    longdblkind=3
    ivtype='long long'
    ivsize=8
    nvtype='double'
    nvsize=8
    Off_t='long long'
    lseeksize=8
    alignbytes=8
    prototype=define
  Linker and Libraries:
    ld='g++.exe'
    ldflags ='-s -L"C:\local\Perl-5.32.1-64bit-portable\perl\lib\CORE" -L"C:\local\Perl-5.32.1-64bit-portable\c\lib"'
    libpth=C:\local\Perl-5.32.1-64bit-portable\c\lib C:\local\Perl-5.32.1-64bit-portable\c\x86_64-w64-mingw32\lib C:\local\Perl-5.32.1-64bit-portable\c\lib\gcc\x86_64-w64-mingw32\8.3.0
    libs= -lmoldname -lkernel32 -luser32 -lgdi32 -lwinspool -lcomdlg32 -ladvapi32 -lshell32 -lole32 -loleaut32 -lnetapi32 -luuid -lws2_32 -lmpr -lwinmm -lversion -lodbc32 -lodbccp32 -lcomctl32
    perllibs= -lmoldname -lkernel32 -luser32 -lgdi32 -lwinspool -lcomdlg32 -ladvapi32 -lshell32 -lole32 -loleaut32 -lnetapi32 -luuid -lws2_32 -lmpr -lwinmm -lversion -lodbc32 -lodbccp32 -lcomctl32
    libc=
    so=dll
    useshrplib=true
    libperl=libperl532.a
    gnulibc_version=''
  Dynamic Linking:
    dlsrc=dl_win32.xs
    dlext=xs.dll
    d_dlsymun=undef
    ccdlflags=' '
    cccdlflags=' '
    lddlflags='-mdll -s -L"C:\local\Perl-5.32.1-64bit-portable\perl\lib\CORE" -L"C:\local\Perl-5.32.1-64bit-portable\c\lib"'


Characteristics of this binary (from libperl):
  Compile-time options:
    HAS_TIMES
    HAVE_INTERP_INTERN
    MULTIPLICITY
    PERLIO_LAYERS
    PERL_COPY_ON_WRITE
    PERL_DONT_CREATE_GVSV
    PERL_IMPLICIT_CONTEXT
    PERL_IMPLICIT_SYS
    PERL_MALLOC_WRAP
    PERL_OP_PARENT
    PERL_PRESERVE_IVUV
    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
  Built under MSWin32
  Compiled at Jan 24 2021 15:05:42
  @INC:
    C:/local/Perl-5.32.1-64bit-portable/perl/site/lib
    C:/local/Perl-5.32.1-64bit-portable/perl/vendor/lib
    C:/local/Perl-5.32.1-64bit-portable/perl/lib

Answer 1

当我试图进一步缩小示例脚本的范围时，我终于明白了这一点：

与我一直认为的相反，即使在从#!perl -W命令提示符通过perl script.pl运行时，脚本开始时也会解释该特定形式的shebang行。

在这里我们有：

...
-W                enable all warnings
...

如果我删除行(在我们的Windows环境中不需要)或将其更改为-w (小写)，那么这些警告就会消失。