Front page | perl.perl5.porters |
Postings from January 2015
[perl #123665] 'Useless use of a constant in void context' is compile-time but not syntax warning
Thread Previous
From:
Ed Avis
Date:
January 24, 2015 08:06
Subject:
[perl #123665] 'Useless use of a constant in void context' is compile-time but not syntax warning
Message ID:
rt-4.0.18-23096-1422086782-120.123665-75-0@perl.org
# New Ticket Created by "Ed Avis"
# Please include the string: [perl #123665]
# in the subject line of all future correspondence about this issue.
# <URL: https://rt.perl.org/Ticket/Display.html?id=123665 >
This is a bug report for perl from eda@waniasset.com,
generated with the help of perlbug 1.39 running under perl 5.18.4.
-----------------------------------------------------------------
[Please describe your issue here]
This program warns 'Useless use of a constant ("a") in void context':
#!/usr/bin/perl
use strict;
use warnings;
use 5.018;
use warnings FATAL => 'syntax';
sub x { 'a'; return 0 }
say 'ok';
Since x() is never called the warning must be compile time. Yet
it is not made FATAL.
Now it is not really a syntax error, more a semantic check, so I can
see how it is not included as 'syntax'. I would like to make all
compilation warnings fatal without making run-time warnings fatal.
Perhaps that could be done using a BEGIN block and so on. Could
that feature be added to warnings.pm, as
use warnings FATAL => 'compilation';
[Please do not change anything below this line]
-----------------------------------------------------------------
---
Flags:
category=core
severity=low
---
Site configuration information for perl 5.18.4:
Configured by Red Hat, Inc. at Thu Oct 30 14:55:21 UTC 2014.
Summary of my perl5 (revision 5 version 18 subversion 4) configuration:
Platform:
osname=linux, osvers=3.16.3-200.fc20.x86_64, archname=x86_64-linux-thread-multi
uname='linux buildvm-18.phx2.fedoraproject.org 3.16.3-200.fc20.x86_64 #1 smp wed sep 17 22:34:21 utc 2014 x86_64 x86_64 x86_64 gnulinux '
config_args='-des -Doptimize=-O2 -g -pipe -Wall -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fstack-protector-strong --param=ssp-buffer-size=4 -grecord-gcc-switches -m64 -mtune=generic -Dccdlflags=-Wl,--enable-new-dtags -Dlddlflags=-shared -O2 -g -pipe -Wall -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fstack-protector-strong --param=ssp-buffer-size=4 -grecord-gcc-switches -m64 -mtune=generic -Wl,-z,relro -Dshrpdir=/usr/lib64 -DDEBUGGING=-g -Dversion=5.18.4 -Dmyhostname=localhost -Dperladmin=root@localhost -Dcc=gcc -Dcf_by=Red Hat, Inc. -Dprefix=/usr -Dvendorprefix=/usr -Dsiteprefix=/usr/local -Dsitelib=/usr/local/share/perl5 -Dsitearch=/usr/local/lib64/perl5 -Dprivlib=/usr/share/perl5 -Dvendorlib=/usr/share/perl5/vendor_perl -Darchlib=/usr/lib64/perl5 -Dvendorarch=/usr/lib64/perl5/vendor_perl -Darchname=x86_64-linux-thread-multi -Dlibpth=/usr/local/lib64 /lib64 /usr/lib64 -Duseshrplib -Dusethreads -Duseithreads -Dusedtrace=/usr/bin/dtrace -Duselargefiles -Dd_semctl_semun -Di_db -Ui
_ndbm -Di_gdbm -Di_shadow -Di_syslog -Dman3ext=3pm -Duseperlio -Dinstallusrbinperl=n -Ubincompat5005 -Uversiononly -Dpager=/usr/bin/less -isr -Dd_gethostent_r_proto -Ud_endhostent_r_proto -Ud_sethostent_r_proto -Ud_endprotoent_r_proto -Ud_setprotoent_r_proto -Ud_endservent_r_proto -Ud_setservent_r_proto -Dscriptdir=/usr/bin -Dusesitecustomize'
hint=recommended, useposix=true, d_sigaction=define
useithreads=define, usemultiplicity=define
useperlio=define, d_sfio=undef, uselargefiles=define, usesocks=undef
use64bitint=define, use64bitall=define, uselongdouble=undef
usemymalloc=n, bincompat5005=undef
Compiler:
cc='gcc', ccflags ='-D_REENTRANT -D_GNU_SOURCE -fno-strict-aliasing -pipe -fstack-protector -I/usr/local/include -D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64',
optimize='-O2 -g -pipe -Wall -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fstack-protector-strong --param=ssp-buffer-size=4 -grecord-gcc-switches -m64 -mtune=generic',
cppflags='-D_REENTRANT -D_GNU_SOURCE -fno-strict-aliasing -pipe -fstack-protector -I/usr/local/include'
ccversion='', gccversion='4.8.3 20140911 (Red Hat 4.8.3-7)', gccosandvers=''
intsize=4, longsize=8, ptrsize=8, doublesize=8, byteorder=12345678
d_longlong=define, longlongsize=8, d_longdbl=define, longdblsize=16
ivtype='long', ivsize=8, nvtype='double', nvsize=8, Off_t='off_t', lseeksize=8
alignbytes=8, prototype=define
Linker and Libraries:
ld='gcc', ldflags =' -fstack-protector'
libpth=/usr/local/lib64 /lib64 /usr/lib64
libs=-lresolv -lnsl -lgdbm -ldb -ldl -lm -lcrypt -lutil -lpthread -lc -lgdbm_compat
perllibs=-lresolv -lnsl -ldl -lm -lcrypt -lutil -lpthread -lc
libc=, so=so, useshrplib=true, libperl=libperl.so
gnulibc_version='2.18'
Dynamic Linking:
dlsrc=dl_dlopen.xs, dlext=so, d_dlsymun=undef, ccdlflags='-Wl,--enable-new-dtags'
cccdlflags='-fPIC', lddlflags='-shared -O2 -g -pipe -Wall -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fstack-protector-strong --param=ssp-buffer-size=4 -grecord-gcc-switches -m64 -mtune=generic -Wl,-z,relro '
Locally applied patches:
Fedora Patch1: Removes date check, Fedora/RHEL specific
Fedora Patch3: support for libdir64
Fedora Patch4: use libresolv instead of libbind
Fedora Patch5: USE_MM_LD_RUN_PATH
Fedora Patch6: Skip hostname tests, due to builders not being network capable
Fedora Patch7: Dont run one io test due to random builder failures
Fedora Patch9: Fix find2perl to translate ? glob properly (RT#113054)
Fedora Patch10: Update h2ph(1) documentation (RT#117647)
Fedora Patch11: Update pod2html(1) documentation (RT#117623)
Fedora Patch12: Disable ornaments on perl5db AutoTrace tests (RT#118817)
Fedora Patch14: Do not use system Term::ReadLine::Gnu in tests (RT#118821)
Fedora Patch15: Define SONAME for libperl.so
Fedora Patch16: Install libperl.so to -Dshrpdir value
Fedora Patch18: Fix crash with \\&$glob_copy (RT#119051)
Fedora Patch19: Fix coreamp.t rand test (RT#118237)
Fedora Patch20: Reap child in case where exception has been thrown (RT#114722)
Fedora Patch21: Fix using regular expressions containing multiple code blocks (RT#117917)
Fedora Patch22: Create site paths by cpan for the first time (CPAN RT#99905)
Fedora Patch200: Link XS modules to libperl.so with EU::CBuilder on Linux
Fedora Patch201: Link XS modules to libperl.so with EU::MM on Linux
---
@INC for perl 5.18.4:
/home/eda/lib/perl5/
/usr/local/lib64/perl5
/usr/local/share/perl5
/usr/lib64/perl5/vendor_perl
/usr/share/perl5/vendor_perl
/usr/lib64/perl5
/usr/share/perl5
.
---
Environment for perl 5.18.4:
HOME=/home/eda
LANG=en_GB.UTF-8
LANGUAGE (unset)
LC_COLLATE=C
LC_CTYPE=en_GB.UTF-8
LC_MESSAGES=en_GB.UTF-8
LC_MONETARY=en_GB.UTF-8
LC_NUMERIC=en_GB.UTF-8
LC_TIME=en_GB.UTF-8
LD_LIBRARY_PATH (unset)
LOGDIR (unset)
PATH=/home/eda/bin:/home/eda/bin:/usr/local/bin:/usr/bin:/sbin:/usr/sbin:/sbin:/usr/sbin
PERL5LIB=/home/eda/lib/perl5/
PERL_BADLANG (unset)
SHELL=/bin/bash
______________________________________________________________________
This email has been scanned by the Symantec Email Security.cloud service.
For more information please visit http://www.symanteccloud.com
______________________________________________________________________
Thread Previous