Problem with Zlib in JUCE 8.0.7

General JUCE discussion
1

Hello

I just downloaded the new version 8.0.7 and I have problems during the link with Zlib.
The Zlib code is already included in my project, thus some symbols are already defined …

In JUCE 8.0.6, it seems that the Zlib code was inside a namespace called zlibNamespace, thus I had no problem.
There is an old post from Jules on this topic : Using alternative zlib - #2 by jules

Is there a good reason for this change ?
Of course, I can also put my Zlib in a namespace …

2

Please could you provide some more details, such as the exact text of the error you’re seeing? We still include zlib in a zlibNamespace in JUCE 8.0.7, but perhaps we are accidentally including some file outside of this namespace. In any case, it would be helpful to know which symbols are causing problems.

3

Thanks a lot @reuk
Here is the output of Visual Studio :
1>include_juce_core.obj : error LNK2005: zlibVersion already defined in zutil.obj
1>include_juce_core.obj : error LNK2005: deflate already defined in deflate.obj
1>include_juce_core.obj : error LNK2005: deflateEnd already defined in deflate.obj
1>include_juce_core.obj : error LNK2005: inflate already defined in inflate.obj
1>include_juce_core.obj : error LNK2005: inflateEnd already defined in inflate.obj
1>include_juce_core.obj : error LNK2005: deflateSetDictionary already defined in deflate.obj
1>include_juce_core.obj : error LNK2005: deflateGetDictionary already defined in deflate.obj
1>include_juce_core.obj : error LNK2005: deflateCopy already defined in deflate.obj
1>include_juce_core.obj : error LNK2005: deflateReset already defined in deflate.obj
1>include_juce_core.obj : error LNK2005: deflateParams already defined in deflate.obj
1>include_juce_core.obj : error LNK2005: deflateTune already defined in deflate.obj
1>include_juce_core.obj : error LNK2005: deflateBound already defined in deflate.obj
1>include_juce_core.obj : error LNK2005: deflatePending already defined in deflate.obj
1>include_juce_core.obj : error LNK2005: deflatePrime already defined in deflate.obj
1>include_juce_core.obj : error LNK2005: deflateSetHeader already defined in deflate.obj
1>include_juce_core.obj : error LNK2005: inflateSetDictionary already defined in inflate.obj
1>include_juce_core.obj : error LNK2005: inflateGetDictionary already defined in inflate.obj
1>include_juce_core.obj : error LNK2005: inflateSync already defined in inflate.obj
1>include_juce_core.obj : error LNK2005: inflateCopy already defined in inflate.obj
1>include_juce_core.obj : error LNK2005: inflateReset already defined in inflate.obj
1>include_juce_core.obj : error LNK2005: inflateReset2 already defined in inflate.obj
1>include_juce_core.obj : error LNK2005: inflatePrime already defined in inflate.obj
1>include_juce_core.obj : error LNK2005: inflateMark already defined in inflate.obj
1>include_juce_core.obj : error LNK2005: inflateGetHeader already defined in inflate.obj
1>include_juce_core.obj : error LNK2005: zlibCompileFlags already defined in zutil.obj
1>include_juce_core.obj : error LNK2005: compress already defined in compress.obj
1>include_juce_core.obj : error LNK2005: compress2 already defined in compress.obj
1>include_juce_core.obj : error LNK2005: compressBound already defined in compress.obj
1>include_juce_core.obj : error LNK2005: adler32 already defined in adler32.obj
1>include_juce_core.obj : error LNK2005: adler32_z already defined in adler32.obj
1>include_juce_core.obj : error LNK2005: crc32 already defined in crc32.obj
1>include_juce_core.obj : error LNK2005: crc32_z already defined in crc32.obj
1>include_juce_core.obj : error LNK2005: crc32_combine_op already defined in crc32.obj
1>include_juce_core.obj : error LNK2005: deflateInit_ already defined in deflate.obj
1>include_juce_core.obj : error LNK2005: inflateInit_ already defined in inflate.obj
1>include_juce_core.obj : error LNK2005: deflateInit2_ already defined in deflate.obj
1>include_juce_core.obj : error LNK2005: inflateInit2_ already defined in inflate.obj
1>include_juce_core.obj : error LNK2005: adler32_combine already defined in adler32.obj
1>include_juce_core.obj : error LNK2005: crc32_combine already defined in crc32.obj
1>include_juce_core.obj : error LNK2005: crc32_combine_gen already defined in crc32.obj
1>include_juce_core.obj : error LNK2005: zError already defined in zutil.obj
1>include_juce_core.obj : error LNK2005: inflateSyncPoint already defined in inflate.obj
1>include_juce_core.obj : error LNK2005: get_crc_table already defined in crc32.obj
1>include_juce_core.obj : error LNK2005: inflateUndermine already defined in inflate.obj
1>include_juce_core.obj : error LNK2005: inflateValidate already defined in inflate.obj
1>include_juce_core.obj : error LNK2005: inflateCodesUsed already defined in inflate.obj
1>include_juce_core.obj : error LNK2005: inflateResetKeep already defined in inflate.obj
1>include_juce_core.obj : error LNK2005: deflateResetKeep already defined in deflate.obj

4

I think I see the problem - the bundled zlib.h wraps all declarations with extern "C", which uses C-style symbol naming that omits the C++ namespace. In the previous bundled zlib, the extern "C" was commented out.

I’ll update this thread once a fix is published.

2 Likes
5

To follow up, that was fixed here:

1 Like
6

Thanks a lot @reuk , it solves the problem.

1 Like