<h3 dir="auto">Bug report</h3>
<p dir="auto"><code class="notranslate">pip install matplotlib</code> fails today on <code class="notranslate">kiwisolver</code> error on Mac.  Something broke on <code class="notranslate">kiwisolver</code> update that was pushed recently (<a href="https://pypi.org/project/kiwisolver/#history" rel="nofollow">https://pypi.org/project/kiwisolver/#history</a>).  Related issue - <a class="issue-link js-issue-link" data-error-text="Failed to load title" data-id="437443038" data-permission-text="Title is private" data-url="https://github.com/nucleic/kiwi/issues/66" data-hovercard-type="issue" data-hovercard-url="/nucleic/kiwi/issues/66/hovercard" href="https://github.com/nucleic/kiwi/issues/66">nucleic/kiwi#66</a></p>
<p dir="auto"><strong>Code for reproduction</strong></p>
<div class="highlight highlight-source-shell notranslate position-relative overflow-auto" dir="auto" data-snippet-clipboard-copy-content="conda create -n kiwi-bug python-3.6
conda activate kiwi-bug . # or source activate kiwi-bug
pip install matplotlib"><pre class="notranslate">conda create -n kiwi-bug python-3.6
conda activate kiwi-bug <span class="pl-c1">.</span> <span class="pl-c"><span class="pl-c">#</span> or source activate kiwi-bug</span>
pip install matplotlib</pre></div>
<p dir="auto"><strong>Actual outcome</strong></p>
<p dir="auto"><a target="_blank" rel="noopener noreferrer nofollow" href="https://user-images.githubusercontent.com/1437573/56776770-e52f4300-6782-11e9-8671-8f5cb7d4b41b.png"><img width="1395" alt="Screen Shot 2019-04-25 at 5 52 14 PM" src="https://user-images.githubusercontent.com/1437573/56776770-e52f4300-6782-11e9-8671-8f5cb7d4b41b.png" style="max-width: 100%;"></a></p>
<p dir="auto">Since today, when I try to install <code class="notranslate">matplotlib</code> on macOS via <code class="notranslate">pip</code>, the installation fails while trying to build <code class="notranslate">kiwisolver</code>. Can we ensure that all dependencies of <code class="notranslate">matplotlib</code> provide wheels?</p>
<details>
<summary>log</summary>
<pre class="notranslate">    ...
    Building wheels for collected packages: kiwisolver
    Building wheel for kiwisolver (setup.py) ... error
    Complete output from command /Users/goerz/Documents/Programming/github/qdynpylib/.venv/py36/bin/python -u -c "import setuptools, tokenize;__file__='/private/var/folders/ll/rgszt4s525s2xtv8rr60lqz40000gn/T/pip-install-t9u3qteo/kiwisolver/setup.py';f=getattr(tokenize, 'o$
    en', open)(__file__);code=f.read().replace('\r\n', '\n');f.close();exec(compile(code, __file__, 'exec'))" bdist_wheel -d /private/var/folders/ll/rgszt4s525s2xtv8rr60lqz40000gn/T/pip-wheel-gp3bw9o8 --python-tag cp36:
    running bdist_wheel
    running build
    running build_ext
    building 'kiwisolver' extension
    creating build
    creating build/temp.macosx-10.7-x86_64-3.6
    creating build/temp.macosx-10.7-x86_64-3.6/py
    gcc -Wno-unused-result -Wsign-compare -Wunreachable-code -DNDEBUG -g -fwrapv -O3 -Wall -Wstrict-prototypes -I/Users/goerz/Documents/Programming/github/qdynpylib/.venv/py36/include -arch x86_64 -I/Users/goerz/Documents/Programming/github/qdynpylib/.venv/py36/include -ar$
    h x86_64 -I. -I/Users/goerz/Documents/Programming/github/qdynpylib/.venv/py36/include/python3.6m -c py/kiwisolver.cpp -o build/temp.macosx-10.7-x86_64-3.6/py/kiwisolver.o
    warning: include path for stdlibc++ headers not found; pass '-stdlib=libc++' on the command line to use the libc++ standard library instead [-Wstdlibcxx-not-found]
    In file included from py/kiwisolver.cpp:9:
    In file included from ./kiwi/kiwi.h:9:
    ./kiwi/constraint.h:9:10: fatal error: 'map' file not found
    #include 
            ^~~~~
    1 warning and 1 error generated.
    error: command 'gcc' failed with exit status 1
<div class="snippet-clipboard-content notranslate position-relative overflow-auto" data-snippet-clipboard-copy-content="----------------------------------------
Failed building wheel for kiwisolver
Running setup.py clean for kiwisolver
Failed to build kiwisolver
Installing collected packages: mpmath, sympy, click, pyparsing, six, cycler, python-dateutil, kiwisolver, matplotlib, coverage, py, atomicwrites, attrs, pluggy, more-itertools, pytest, pytest-cov, sphinxcontrib-jsmath, docutils, MarkupSafe, jinja2, snowballstemmer, sphin$
contrib-htmlhelp, imagesize, chardet, urllib3, idna, requests, pytz, babel, sphinxcontrib-serializinghtml, sphinxcontrib-applehelp, packaging, sphinxcontrib-devhelp, alabaster, sphinxcontrib-qthelp, Pygments, sphinx, better-apidoc, sphinx-autodoc-typehints, isort, appdir$
, toml, black, decorator, ipython-genutils, traitlets, pyrsistent, jsonschema, jupyter-core, nbformat, webencodings, bleach, mistune, testpath, defusedxml, entrypoints, pandocfilters, nbconvert, tornado, ptyprocess, terminado, pyzmq, Send2Trash, jupyter-client, appnope, $
cwidth, prompt-toolkit, pickleshare, pexpect, parso, jedi, backcall, ipython, ipykernel, prometheus-client, notebook, jupyter-console, widgetsnbextension, ipywidgets, qtconsole, jupyter, argh, PyYAML, pathtools, watchdog, port-for, livereload, sphinx-autobuild, sphinx-rt$
-theme, smmap2, gitdb2, gitpython, apipkg, execnet, pytest-forked, pytest-xdist, watermark, virtualenv, nodeenv, zipp, importlib-metadata, identify, cfgv, importlib-resources, aspy.yaml, pre-commit, pep8, nbval, pycodestyle, pyflakes, mccabe, flake8, readme-renderer, req$
ests-toolbelt, pkginfo, tqdm, twine, nbsphinx, qdyn
Running setup.py install for kiwisolver ... error
    Complete output from command /Users/goerz/Documents/Programming/github/qdynpylib/.venv/py36/bin/python -u -c &quot;import setuptools, tokenize;__file__='/private/var/folders/ll/rgszt4s525s2xtv8rr60lqz40000gn/T/pip-install-t9u3qteo/kiwisolver/setup.py';f=getattr(tokenize, $
open', open)(__file__);code=f.read().replace('\r\n', '\n');f.close();exec(compile(code, __file__, 'exec'))&quot; install --record /private/var/folders/ll/rgszt4s525s2xtv8rr60lqz40000gn/T/pip-record-dv16j2ct/install-record.txt --single-version-externally-managed --compile:
    running install
    running build
    running build_ext
    building 'kiwisolver' extension
    creating build
    creating build/temp.macosx-10.7-x86_64-3.6
    creating build/temp.macosx-10.7-x86_64-3.6/py
    gcc -Wno-unused-result -Wsign-compare -Wunreachable-code -DNDEBUG -g -fwrapv -O3 -Wall -Wstrict-prototypes -I/Users/goerz/Documents/Programming/github/qdynpylib/.venv/py36/include -arch x86_64 -I/Users/goerz/Documents/Programming/github/qdynpylib/.venv/py36/include -$
rch x86_64 -I. -I/Users/goerz/Documents/Programming/github/qdynpylib/.venv/py36/include/python3.6m -c py/kiwisolver.cpp -o build/temp.macosx-10.7-x86_64-3.6/py/kiwisolver.o
    warning: include path for stdlibc++ headers not found; pass '-stdlib=libc++' on the command line to use the libc++ standard library instead [-Wstdlibcxx-not-found]
    In file included from py/kiwisolver.cpp:9:
    In file included from ./kiwi/kiwi.h:9:
    ./kiwi/constraint.h:9:10: fatal error: 'map' file not found
    #include &lt;map&gt;
            ^~~~~
    1 warning and 1 error generated.
    error: command 'gcc' failed with exit status 1

    ----------------------------------------
Command &quot;/Users/goerz/Documents/Programming/github/qdynpylib/.venv/py36/bin/python -u -c &quot;import setuptools, tokenize;__file__='/private/var/folders/ll/rgszt4s525s2xtv8rr60lqz40000gn/T/pip-install-t9u3qteo/kiwisolver/setup.py';f=getattr(tokenize, 'open', open)(__file__);$
ode=f.read().replace('\r\n', '\n');f.close();exec(compile(code, __file__, 'exec'))&quot; install --record /private/var/folders/ll/rgszt4s525s2xtv8rr60lqz40000gn/T/pip-record-dv16j2ct/install-record.txt --single-version-externally-managed --compile&quot; failed with error code 1 in
/private/var/folders/ll/rgszt4s525s2xtv8rr60lqz40000gn/T/pip-install-t9u3qteo/kiwisolver/
make: *** [.venv/py36/bin/py.test] Error 1"><pre class="notranslate"><code class="notranslate">----------------------------------------
Failed building wheel for kiwisolver
Running setup.py clean for kiwisolver
Failed to build kiwisolver
Installing collected packages: mpmath, sympy, click, pyparsing, six, cycler, python-dateutil, kiwisolver, matplotlib, coverage, py, atomicwrites, attrs, pluggy, more-itertools, pytest, pytest-cov, sphinxcontrib-jsmath, docutils, MarkupSafe, jinja2, snowballstemmer, sphin$
contrib-htmlhelp, imagesize, chardet, urllib3, idna, requests, pytz, babel, sphinxcontrib-serializinghtml, sphinxcontrib-applehelp, packaging, sphinxcontrib-devhelp, alabaster, sphinxcontrib-qthelp, Pygments, sphinx, better-apidoc, sphinx-autodoc-typehints, isort, appdir$
, toml, black, decorator, ipython-genutils, traitlets, pyrsistent, jsonschema, jupyter-core, nbformat, webencodings, bleach, mistune, testpath, defusedxml, entrypoints, pandocfilters, nbconvert, tornado, ptyprocess, terminado, pyzmq, Send2Trash, jupyter-client, appnope, $
cwidth, prompt-toolkit, pickleshare, pexpect, parso, jedi, backcall, ipython, ipykernel, prometheus-client, notebook, jupyter-console, widgetsnbextension, ipywidgets, qtconsole, jupyter, argh, PyYAML, pathtools, watchdog, port-for, livereload, sphinx-autobuild, sphinx-rt$
-theme, smmap2, gitdb2, gitpython, apipkg, execnet, pytest-forked, pytest-xdist, watermark, virtualenv, nodeenv, zipp, importlib-metadata, identify, cfgv, importlib-resources, aspy.yaml, pre-commit, pep8, nbval, pycodestyle, pyflakes, mccabe, flake8, readme-renderer, req$
ests-toolbelt, pkginfo, tqdm, twine, nbsphinx, qdyn
Running setup.py install for kiwisolver ... error
    Complete output from command /Users/goerz/Documents/Programming/github/qdynpylib/.venv/py36/bin/python -u -c "import setuptools, tokenize;__file__='/private/var/folders/ll/rgszt4s525s2xtv8rr60lqz40000gn/T/pip-install-t9u3qteo/kiwisolver/setup.py';f=getattr(tokenize, $
open', open)(__file__);code=f.read().replace('\r\n', '\n');f.close();exec(compile(code, __file__, 'exec'))" install --record /private/var/folders/ll/rgszt4s525s2xtv8rr60lqz40000gn/T/pip-record-dv16j2ct/install-record.txt --single-version-externally-managed --compile:
    running install
    running build
    running build_ext
    building 'kiwisolver' extension
    creating build
    creating build/temp.macosx-10.7-x86_64-3.6
    creating build/temp.macosx-10.7-x86_64-3.6/py
    gcc -Wno-unused-result -Wsign-compare -Wunreachable-code -DNDEBUG -g -fwrapv -O3 -Wall -Wstrict-prototypes -I/Users/goerz/Documents/Programming/github/qdynpylib/.venv/py36/include -arch x86_64 -I/Users/goerz/Documents/Programming/github/qdynpylib/.venv/py36/include -$
rch x86_64 -I. -I/Users/goerz/Documents/Programming/github/qdynpylib/.venv/py36/include/python3.6m -c py/kiwisolver.cpp -o build/temp.macosx-10.7-x86_64-3.6/py/kiwisolver.o
    warning: include path for stdlibc++ headers not found; pass '-stdlib=libc++' on the command line to use the libc++ standard library instead [-Wstdlibcxx-not-found]
    In file included from py/kiwisolver.cpp:9:
    In file included from ./kiwi/kiwi.h:9:
    ./kiwi/constraint.h:9:10: fatal error: 'map' file not found
    #include &lt;map&gt;
            ^~~~~
    1 warning and 1 error generated.
    error: command 'gcc' failed with exit status 1

    ----------------------------------------
Command "/Users/goerz/Documents/Programming/github/qdynpylib/.venv/py36/bin/python -u -c "import setuptools, tokenize;__file__='/private/var/folders/ll/rgszt4s525s2xtv8rr60lqz40000gn/T/pip-install-t9u3qteo/kiwisolver/setup.py';f=getattr(tokenize, 'open', open)(__file__);$
ode=f.read().replace('\r\n', '\n');f.close();exec(compile(code, __file__, 'exec'))" install --record /private/var/folders/ll/rgszt4s525s2xtv8rr60lqz40000gn/T/pip-record-dv16j2ct/install-record.txt --single-version-externally-managed --compile" failed with error code 1 in
/private/var/folders/ll/rgszt4s525s2xtv8rr60lqz40000gn/T/pip-install-t9u3qteo/kiwisolver/
make: *** [.venv/py36/bin/py.test] Error 1
</code></pre></div>
</pre>
</details>