openexr: ZLIB_LIBRARY ZLIB_INCLUDE_DIR being ignored (LNK2019 errors) in OpenEXR\IlmImf\IlmImf.vcxproj

In windows 10 x64; using VS2017; using cmake 3.13.14 and a powershell script.

I have multiple LNK2019 error, despite a correct configuration:

ImfDwaCompressor.obj : error LNK2019: unresolved external symbol compress2 referenced in function "private: int __cdecl
 Imf_2_3::DwaCompressor::compress(char const *,int,class Imath_2_3::Box<class Imath_2_3::Vec2<int> >,char const * &)" (
?compress@DwaCompressor@Imf_2_3@@AEAAHPEBDHV?$Box@V?$Vec2@H@Imath_2_3@@@Imath_2_3@@AEAPEBD@Z) [I:\lib\master-openexr\bu
ild\OpenEXR\IlmImf\IlmImf.vcxproj]
ImfDwaCompressor.obj : error LNK2019: unresolved external symbol compressBound referenced in function "private: int __c
decl Imf_2_3::DwaCompressor::compress(char const *,int,class Imath_2_3::Box<class Imath_2_3::Vec2<int> >,char const * &
)" (?compress@DwaCompressor@Imf_2_3@@AEAAHPEBDHV?$Box@V?$Vec2@H@Imath_2_3@@@Imath_2_3@@AEAPEBD@Z) [I:\lib\master-openex
r\build\OpenEXR\IlmImf\IlmImf.vcxproj]
ImfDwaCompressor.obj : error LNK2019: unresolved external symbol uncompress referenced in function "private: int __cdec
l Imf_2_3::DwaCompressor::uncompress(char const *,int,class Imath_2_3::Box<class Imath_2_3::Vec2<int> >,char const * &)
" (?uncompress@DwaCompressor@Imf_2_3@@AEAAHPEBDHV?$Box@V?$Vec2@H@Imath_2_3@@@Imath_2_3@@AEAPEBD@Z) [I:\lib\master-opene
xr\build\OpenEXR\IlmImf\IlmImf.vcxproj]
ImfPxr24Compressor.obj : error LNK2001: unresolved external symbol uncompress [I:\lib\master-openexr\build\OpenEXR\IlmI
mf\IlmImf.vcxproj]
ImfZip.obj : error LNK2001: unresolved external symbol uncompress [I:\lib\master-openexr\build\OpenEXR\IlmImf\IlmImf.vc
xproj]
ImfPxr24Compressor.obj : error LNK2019: unresolved external symbol compress referenced in function "private: int __cdec
l Imf_2_3::Pxr24Compressor::compress(char const *,int,class Imath_2_3::Box<class Imath_2_3::Vec2<int> >,char const * &)
" (?compress@Pxr24Compressor@Imf_2_3@@AEAAHPEBDHV?$Box@V?$Vec2@H@Imath_2_3@@@Imath_2_3@@AEAPEBD@Z) [I:\lib\master-opene
xr\build\OpenEXR\IlmImf\IlmImf.vcxproj]
ImfZip.obj : error LNK2001: unresolved external symbol compress [I:\lib\master-openexr\build\OpenEXR\IlmImf\IlmImf.vcxp
roj]
I:\lib\master-openexr\build\OpenEXR\IlmImf\Release\IlmImf-2_3.dll : fatal error LNK1120: 4 unresolved externals [I:\lib
\master-openexr\build\OpenEXR\IlmImf\IlmImf.vcxproj]

Repro: using zlib 1.2.11, compiled in Win64 at I:\lib\zlib

I configure and build openexr with this script:

$target = "Visual Studio 15 2017 Win64"
$zlib_prefix = "I:\lib\zlib"

function configure {
	cmake.exe -G $target -T v141, host=x64 -j8 `
		-DZLIB_LIBRARY="${zlib_prefix}\lib" -DZLIB_INCLUDE_DIR="${zlib_prefix}\include" `
		-DOPENEXR_BUILD_PYTHON_LIBS=0 -DCMAKE_INSTALL_PREFIX="I:\lib\openexr" `
		..
}

function build {
	"build openexr debug"
	MSBuild.exe OpenEXR.sln /verbosity:m /m
	"build openexr release"
	MSBuild.exe OpenEXR.sln /p:Configuration=Release /verbosity:m /m
}

function install {
	"install openexr debug"
	MSBuild.exe INSTALL.vcxproj /verbosity:m /m
	"install openexr release"
	MSBuild.exe INSTALL.vcxproj /p:Configuration=Release /verbosity:m /m
}

if (!(test-path build)) {
	New-Item -ItemType Directory build
}
Set-Location build
configure
build
#install
Set-Location ..

Proof: hand-edit IlmImf.vcxproj to use the zlib.lib and zlibd.lib provided works.

About this issue

Original URL
State: closed
Created 5 years ago
Comments: 17 (10 by maintainers)

Most upvoted comments

Okay, I went through all the documentation I could find, and the implementation, and compared a bunch of projects on github, some of which do indeed use ZLIB_LIBRARY as an input.

quick summary

ZLIB_LIBRARIES is the variable to set, according to the documentation, and it’s what OpenEXR expects. I think this is the right thing to do, even if some projects don’t do it.
OpenEXR erroneously uses ZLIB_INCLUDE_DIR, which is an error in the OpenEXR Cmake files and should be corrected.

details:

https://cmake.org/cmake/help/latest/module/FindZLIB.html

OpenExr looks for ZLIB_INCLUDE_DIR in OpenEXR/CMakeLists.txt, but according to the FindZLIB documentation, it should be looking for ZLIB_INCLUDE_DIRS.

 MACRO(SET_ILMBASE_INCLUDE_DIRS _target)
    TARGET_INCLUDE_DIRECTORIES(${_target}
     PRIVATE ${ZLIB_INCLUDE_DIR}
     PRIVATE ${CMAKE_CURRENT_BINARY_DIR}/../config
     PRIVATE ${CMAKE_CURRENT_BINARY_DIR}/../../IlmBase/config

So this is an error in OpenEXR’s cmake scripts.

According to the documentation, using ZLIB_ROOT should be sufficient to set ZLIB_INCLUDE_DIRS and ZLIB_LIBRARIES. Nonetheless, since you only had to edit the vcxproj to add zlib references, setting -DZLIB_LIBRARIES in your script instead of ZLIB_LIBRARY should solve your problem.

I understand that other projects are successfully using ZLIB_LIBRARY, but the implementation itself

https://github.com/Kitware/CMake/blob/master/Modules/FindZLIB.cmake

specifies ZLIB_LIBRARY as an input to FindZLIB, used to set ZLIB_LIBRARIES.

Result Variables
^^^^^^^^^^^^^^^^

This module defines the following variables:

::

  ZLIB_INCLUDE_DIRS   - where to find zlib.h, etc.
  ZLIB_LIBRARIES      - List of libraries when using zlib.
  ZLIB_FOUND - True if zlib found.

As an interesting point in comparison, conan’s FindZlib script was updated to use ZLIB_LIBRARIES only, which broke some of their dependent packages, so they had to add ZLIB_LIBRARY back in as an exposed variable. https://github.com/conan-community/community/issues/153 They too preferred to stick to documented outputs.

meshula on Apr 19, 2019

Yes. I downloaded the sources from master the 14th of april.

mprevot on Apr 17, 2019