[PATCH] time64.c tweaks

[p5pRT]

Migrated from rt.perl.org#130121 (status was 'rejected')

Searchable as RT130121$

[p5pRT]

From @petdance

Created by @petdance

Two small tweaks in time64.c

* The struct TM * to S_timegm64 is not modified, so make it be
a const and let the compiler know it won't get modified.

* Localize a variable in the Perl_gmtime64_r function to its
two innermost scopes.

Perl Info

Flags:
    category=core
    severity=low
    Type=Patch
    PatchStatus=HasPatch

Site configuration information for perl 5.24.0:

Configured by andy at Sun Jun  5 23:28:46 CDT 2016.

Summary of my perl5 (revision 5 version 24 subversion 0) configuration:
   
  Platform:
    osname=linux, osvers=3.10.0-327.18.2.el7.x86_64, archname=x86_64-linux
    uname='linux clifford 3.10.0-327.18.2.el7.x86_64 #1 smp thu may 12 11:03:55 utc 2016 x86_64 x86_64 x86_64 gnulinux '
    config_args='-de -Dprefix=/home/andy/perl5/perlbrew/perls/perl-5.24.0 -Aeval:scriptdir=/home/andy/perl5/perlbrew/perls/perl-5.24.0/bin'
    hint=recommended, useposix=true, d_sigaction=define
    useithreads=undef, usemultiplicity=undef
    use64bitint=define, use64bitall=define, uselongdouble=undef
    usemymalloc=n, bincompat5005=undef
  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='4.8.5 20150623 (Red Hat 4.8.5-4)', 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 /lib/../lib64 /usr/lib/../lib64 /lib /lib64 /usr/lib64 /usr/local/lib64
    libs=-lpthread -lnsl -ldl -lm -lcrypt -lutil -lc
    perllibs=-lpthread -lnsl -ldl -lm -lcrypt -lutil -lc
    libc=libc-2.17.so, so=so, useshrplib=false, libperl=libperl.a
    gnulibc_version='2.17'
  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'

Locally applied patches:
    Devel::PatchPerl 1.38


@INC for perl 5.24.0:
    /home/andy/perl5/perlbrew/perls/perl-5.24.0/lib/site_perl/5.24.0/x86_64-linux
    /home/andy/perl5/perlbrew/perls/perl-5.24.0/lib/site_perl/5.24.0
    /home/andy/perl5/perlbrew/perls/perl-5.24.0/lib/5.24.0/x86_64-linux
    /home/andy/perl5/perlbrew/perls/perl-5.24.0/lib/5.24.0
    .


Environment for perl 5.24.0:
    HOME=/home/andy
    LANG=en_US.UTF-8
    LANGUAGE (unset)
    LD_LIBRARY_PATH (unset)
    LOGDIR (unset)
    PATH=/home/andy/perl5/perlbrew/bin:/home/andy/perl5/perlbrew/perls/perl-5.24.0/bin:/home/andy/bin:/usr/sbin:/sbin:/usr/local/bin:/usr/bin:/usr/local/sbin:/usr/sbin
    PERLBREW_BASHRC_VERSION=0.75
    PERLBREW_HOME=/home/andy/.perlbrew
    PERLBREW_MANPATH=/home/andy/perl5/perlbrew/perls/perl-5.24.0/man
    PERLBREW_PATH=/home/andy/perl5/perlbrew/bin:/home/andy/perl5/perlbrew/perls/perl-5.24.0/bin
    PERLBREW_PERL=perl-5.24.0
    PERLBREW_ROOT=/home/andy/perl5/perlbrew
    PERLBREW_VERSION=0.75
    PERLCRITIC=/home/andy/tw/Dev/perlcriticrc
    PERL_BADLANG (unset)
    SHELL=/bin/bash

[p5pRT]

From @petdance

time64.diff

diff --git a/time64.c b/time64.c
index f6ec740..9572180 100644
--- a/time64.c
+++ b/time64.c
@@ -124,7 +124,7 @@ static int S_is_exception_century(Year year)
 }
 
 
-static Time64_T S_timegm64(struct TM *date) {
+static Time64_T S_timegm64(const struct TM *date) {
     int      days    = 0;
     Time64_T seconds = 0;
 
@@ -340,7 +340,6 @@ struct TM *Perl_gmtime64_r (const Time64_T *in_time, struct TM *p)
     Time64_T m;
     Time64_T time = *in_time;
     Year year = 70;
-    int cycles = 0;
 
     assert(p != NULL);
 
@@ -389,7 +388,7 @@ struct TM *Perl_gmtime64_r (const Time64_T *in_time, struct TM *p)
 
     if (m >= 0) {
         /* Gregorian cycles, this is huge optimization for distant times */
-        cycles = (int)Perl_floor(m / (Time64_T) days_in_gregorian_cycle);
+        const int cycles = (int)Perl_floor(m / (Time64_T) days_in_gregorian_cycle);
         if( cycles ) {
             m -= (cycles * (Time64_T) days_in_gregorian_cycle);
             year += (cycles * years_in_gregorian_cycle);
@@ -410,6 +409,8 @@ struct TM *Perl_gmtime64_r (const Time64_T *in_time, struct TM *p)
             v_tm_mon++;
         }
     } else {
+        int cycles;
+
         year--;
 
         /* Gregorian cycles */

[p5pRT]

From @petdance

Closing this ticket in favor of a new patch in #130128

[p5pRT]

@petdance - Status changed from 'new' to 'rejected'