How to link compress2, uncompress and compress on 64 bit Windows 7 & Visual Studio 2015 when building openexr?

[ghost]

On Windows 7 64 bit and Visual Studio 2015, I have built zlib 1.2.11 and now I am trying to build openexr which depends on zlib. But I met with errors as follows:

4>  Generating Code...
4>     Creating library C:/Users/Admin/Downloads/openexr-2.2.0/build/IlmImf/Release/IlmImf-2_2.lib and object C:/Users/Admin/Downloads/openexr-2.2.0/build/IlmImf/Release/IlmImf-2_2.exp
4>ImfDwaCompressor.obj : error LNK2019: unresolved external symbol compress2 referenced in function "private: int __cdecl Imf_2_2::DwaCompressor::compress(char const *,int,class Imath_2_2::Box<class Imath_2_2::Vec2<int> >,char const * &)" (?compress@DwaCompressor@Imf_2_2@@AEAAHPEBDHV?$Box@V?$Vec2@H@Imath_2_2@@@Imath_2_2@@AEAPEBD@Z)
4>ImfDwaCompressor.obj : error LNK2019: unresolved external symbol uncompress referenced in function "private: int __cdecl Imf_2_2::DwaCompressor::uncompress(char const *,int,class Imath_2_2::Box<class Imath_2_2::Vec2<int> >,char const * &)" (?uncompress@DwaCompressor@Imf_2_2@@AEAAHPEBDHV?$Box@V?$Vec2@H@Imath_2_2@@@Imath_2_2@@AEAPEBD@Z)
4>ImfPxr24Compressor.obj : error LNK2001: unresolved external symbol uncompress
4>ImfZip.obj : error LNK2001: unresolved external symbol uncompress
4>ImfPxr24Compressor.obj : error LNK2019: unresolved external symbol compress referenced in function "private: int __cdecl Imf_2_2::Pxr24Compressor::compress(char const *,int,class Imath_2_2::Box<class Imath_2_2::Vec2<int> >,char const * &)" (?compress@Pxr24Compressor@Imf_2_2@@AEAAHPEBDHV?$Box@V?$Vec2@H@Imath_2_2@@@Imath_2_2@@AEAPEBD@Z)
4>ImfZip.obj : error LNK2001: unresolved external symbol compress
4>C:\Users\Admin\Downloads\openexr-2.2.0\build\IlmImf\Release\IlmImf-2_2.dll : fatal error LNK1120: 3 unresolved externals

But the three functions compress2, uncompress and compress are exposed from zlib.lib. I can prove it by dumpbin:

      1    0 00001000 adler32
      2    1 00001010 adler32_combine
      3    2 000010F0 adler32_z
      4    3 000013D0 compress
      5    4 000013F0 compress2
      6    5 000014F0 compressBound
      7    6 00001510 crc32
      8    7 00001520 crc32_combine
      ... ...

How to fix this issue? Was the linker trying to link zlib.lib or zlibstatic.lib which exposes nothing? Can I force openexr to link to zlib.lib?

The cmake command to config zlib is:

cmake
-DCMAKE_INSTALL_PREFIX:STRING=C:/Users/Admin/Downloads/OIIO/external/zlib-1.2.11
-G "Visual Studio 14 2015 Win64" ..

and the cmake command to config openexr is:

cmake
-DILMBASE_PACKAGE_PREFIX:STRING=C:/Users/Admin/Downloads/OIIO/external/ilmbase-2.2.0
-DCMAKE_INSTALL_PREFIX:STRING=C:/Users/Admin/Downloads/OIIO/external/openexr-2.2.0
-DZLIB_LIBRARY:STRING=C:/Users/Admin/Downloads/OIIO/external/zlib-1.2.11/lib -DZLIB_INCLUDE_DIR:STRING=C:/Users/Admin/Downloads/OIIO/external/zlib-1.2.11/include -G "Visual Studio 14 2015 Win64" ..

They look correct and I didn't change anything else. So how to link these 3 functions to openexr (or IlmImf)? Thanks a lot for your help!

[meshula]

I'm wondering if you've build zlib static, and OpenEXR wants zlib dynamic, or vice versa?

[ghost]

OK, I found out where the problem is. I should use -DZLIB_ROOT="C:\Users\Admin\Downloads\OIIO\external\zlib-1.2.11" to specify the location of zlib, but I was misled by this link to use ZLIB_LIBRARY and ZLIB_INCLUDE_DIR for the same purpose, as you can see in my original thread. So, after correcting the cmake command, I got openexr as desired. To clarify, the correct cmake command is:

cmake -DILMBASE_PACKAGE_PREFIX:STRING=C:/Users/Admin/Downloads/OIIO/external/ilmbase-2.2.0 -DCMAKE_INSTALL_PREFIX:STRING=C:/Users/Admin/Downloads/OIIO/external/openexr-2.2.0 -DZLIB_ROOT="C:\Users\Admin\Downloads\OIIO\external\zlib-1.2.11" -G"Visual Studio 14 2015 Win64" ..

PS: I think nowadays at least 80% information in internet are wrong. Documents of some well-known libraries are still talking about 32 bit. Who is using 32 bit CPU today? I saw everyone use 64 bit OS more than 5 years ago. Sigh...

[meshula]

Yuck!
Well, glad you figured it out!

[ghost]

I think the ZLIB_LIBRARY variable should be set to a lib file like zlib.lib but I set it to the lib folder. Maybe that caused the problem. Anyway, ZLIB_ROOT saves us a lot of typing.

[cary-ilm]

Looking into the OpenEXR issue backlog. This issue seems to be resolved, so closing.