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{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"Install on Windows using pkg-config from conda","articleBody":"The current way of installing from sources on Windows involves running the `build_alllocal.cmd` script which manually copies `libz` and `libpng` to the right location. Such approach doesn't work with e.g.,\r\n```\r\npip install https://\u003csome-url\u003e/matplotlib.zip\r\n```\r\nwhere `matplotlib.zip` is the source distribution, taken e.g. from an open PR.\r\n\r\nAs far as I understand, on Linux this is solved by using `pkg-config`. On Windows, `pkg-config` can also be installed from the `msys2` channel which is now parts of the default channel, as,\r\n```\r\nconda install m2w64-pkg-config\r\n```\r\nsee https://github.com/conda-forge/pkg-config-feedstock/issues/11#issuecomment-292950444\r\nThis might help to detect the libpng/freetype libraries (I'm not fully sure), however in any case, install fails while linking libpng,\r\n\r\n\r\n```\r\n[...]\r\n  REQUIRED DEPENDENCIES AND EXTENSIONS\r\n    install_requires: yes [handled by setuptools]\r\n            freetype: yes [Using unknown version found on system.]\r\n                 png: yes [Using unknown version found on system.]\r\n[...]\r\n\r\nC:\\Program Files (x86)\\Microsoft Visual Studio 14.0\\VC\\BIN\\x86_amd64\\link.exe /nologo /INCREMENTAL:NO /LTCG /DLL /MANIFEST:EMBED,ID=2 /MANIFESTUAC:NO /LIBPATH:C:\\ProgramData\\Miniconda3\\envs\\laserbeam-env\\Library\\lib /LIBPATH:C:\\ProgramData\\Miniconda3\\envs\\laserbeam-env\\libs /LIBPATH:C:\\ProgramData\\Miniconda3\\envs\\laserbeam-env\\PCbuild\\amd64 \"/LIBPATH:C:\\Program Files (x86)\\Microsoft Visual Studio 14.0\\VC\\LIB\\amd64\" \"/LIBPATH:C:\\Program Files (x86)\\Windows Kits\\10\\lib\\10.0.10240.0\\ucrt\\x64\" \"/LIBPATH:C:\\Program Files (x86)\\Windows Kits\\8.1\\lib\\winv6.3\\um\\x64\" png.lib z.lib /EXPORT:PyInit__png build\\temp.win-amd64-3.7\\Release\\src/_png.obj build\\temp.win-amd64-3.7\\Release\\src/mplutils.obj /OUT:build\\lib.win-amd64-3.7\\matplotlib\\_png.cp37-win_amd64.pyd /IMPLIB:build\\temp.win-amd64-3.7\\Release\\src\\_png.cp37-win_amd64.lib\r\n    LINK : fatal error LNK1181: cannot open input file 'png.lib'\r\n    error: command 'C:\\\\Program Files (x86)\\\\Microsoft Visual Studio 14.0\\\\VC\\\\BIN\\\\x86_amd64\\\\link.exe' failed with exit status 1181\r\n```\r\nSee [detailed_log.txt](https://github.com/matplotlib/matplotlib/files/2691006/detailed_log.txt) for more details (this builds the https://github.com/matplotlib/matplotlib/pull/11577 PR)\r\n\r\n\r\nI'm wondering if this has anything to do with the fact that `PkgConfig.has_pkgconfig` is hardcoded to False in `setupext.py` when on Windows. \r\n\r\nOpening this issue to track the usage of pkg-config on windows.\r\n\r\n### Versions\r\n\r\n  * Operating system: Windows Server 2016 Datacenter\r\n  * Matplotlib version: master branch\r\n  * Python version: 3.7\r\n\r\nRelated: https://github.com/matplotlib/matplotlib/pull/9693","author":{"url":"https://github.com/rth","@type":"Person","name":"rth"},"datePublished":"2018-12-18T14:59:27.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":8},"url":"https://github.com/13016/matplotlib/issues/13016"}