ImageMagick fails to build since commit 3c357cd "proper chuck length checking" on Ubuntu 16.04 LTS ESM about imagemagick6

[dlemstra]

This issue has been fixed in the most recent version.

[sparrow2009]

If you refer to version 6.9.13.5, this is at least not true for my attempts. The build log excerpt above is actually from an installation attempt of that exact version.

[dlemstra]

I misread your error message but itxt_length has been added in version 1.0.5j of libpng in 1999 so I would advise you to upgrade that.

[sparrow2009]

Well, Ubuntu 16.04 certainly ships with a sufficiently current libpng version (1.2). From the header file:

/* pngconf.h - machine configurable file for libpng
*

• libpng version 1.2.54, November 12, 2015
• Copyright (c) 1998-2015 Glenn Randers-Pehrson
• (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
• (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)

...
*/

From the build log:
...
Options used to compile and link:
PREFIX = /home/some/local/
EXEC-PREFIX = /home/some/local/
VERSION = 6.9.13-2
CC = gcc
CFLAGS = -I/usr/include/libxml2 -I/usr/include/libpng12 -I/usr/include/freetype2 -Wall -g -O2 -mtune=amdfam10 -fexceptions -DMAGICKCORE_HDRI_ENABLE=0 -DMAGICKCORE_QUANTUM_DEPTH=16
CPPFLAGS = -DMAGICKCORE_HDRI_ENABLE=0 -DMAGICKCORE_QUANTUM_DEPTH=16
PCFLAGS =
DEFS = -DHAVE_CONFIG_H
LDFLAGS = -L/home/some/perl5/perlbrew/perls/perl-5.38.2/lib/5.38.2/x86_64-linux/CORE
LIBS = -ljbig -ltiff -lfreetype -ljpeg -lpng12 -llzma -lxml2 -lz -lm
CXX = g++ -std=gnu++11 -std=gnu++11
CXXFLAGS = -g -O2
FEATURES = Cipher DPC
DELEGATES = freetype jbig jng jpeg lzma png ps tiff xml zlib
...

[dlemstra]

It looks like ancient versions of libpng had a check for those members but this changed in 1.4.0 that was released in 2010. That is over 13 years ago so we won't be adding backwards compatibility for that anymore. Upgrade libpng or even better upgrade your ubuntu installation that is now out of support.

[sparrow2009]

Ubuntu 16.04 LTS ESM is under Extended Security Maintenance actually. Upgrading the OS is not an option right now.

libpng is also shipped in version 1.6 as OS package. Building IM6 with freetype support using the libfreetype6 OS package however conflicts with having the OS package libpng16-dev installed.

So this leaves us with dropping the png support when building IM6.

As an aside: You might want to lift your libpng version requirement that is at v1.0.0 if I recall correctly from the build log.
(Still as IM6 is the legacy version of IM it feels somehow wrong to lift a required version of a dependency that much.)