develooper Front page | perl.perl5.porters | Postings from May 2019

[perl #134126] 'make' fails during '-Dusemymalloc' and'-Dusethreads'

Thread Previous
From:
James E Keenan
Date:
May 22, 2019 20:10
Subject:
[perl #134126] 'make' fails during '-Dusemymalloc' and'-Dusethreads'
Message ID:
rt-4.0.24-322-1558555814-495.134126-75-0@perl.org
# New Ticket Created by  James E Keenan 
# Please include the string:  [perl #134126]
# in the subject line of all future correspondence about this issue. 
# <URL: https://rt.perl.org/Ticket/Display.html?id=134126 >


As first suggested by simcop2387 on #p5p, when you attempt to build 
perl5.30.0 using these two configuration switches, the build fails 
during 'make'.  Bisecting on FreeBSD-11.2, I got this result:

#####
f966a6e60c5062904734d261eea96ba070f47fdb is the first bad commit
commit f966a6e60c5062904734d261eea96ba070f47fdb
Author: Karl Williamson <khw@cpan.org>
Date:   Sat Feb 16 11:44:56 2019 -0700

     malloc.c: Limit malloc size to PTRDIFF_MAX

     Without doing this, it is possible that the behavior is undefined when
     subtracting two pointers that point to the same object.

     See thread beginning at
     http://nntp.perl.org/group/perl.perl5.porters/251541

     In particular this from Tomasz Konojacki
...
#####

simcop2387's build report is here:
https://perl.bot/raw/b6nse4

However, I was able to reproduce this on both Linux and FreeBSD-11 with 
the *combination* of "-Dusemymalloc=y -Dusethreads".  "-Dusemymalloc=y" 
by itself built successfully (though I didn't run tests).

Possibly related ticket:
https://rt.perl.org/Ticket/Display.html?id=75972

Bisection command:
git clean -dfx; git bisect reset;perl Porting/bisect.pl --start=v5.29.6 
--test-build -Dusemymalloc=y -Dusethreads

perl perl perl


Thread Previous


nntp.perl.org: Perl Programming lists via nntp and http.
Comments to Ask Bjørn Hansen at ask@perl.org | Group listing | About