Issue 1:
Bug report

When I want to use pyplot from matplotlib, it causes error.

There is no problem with import matplotlib but I cannot use pyplot

Code for reproduction

from matplotlib import pyplot

Actual outcome

---------------------------------------------
FileNotFoundErrorTraceback (most recent call last)
/usr/lib64/python3.6/site-packages/matplotlib/font_manager.py in <module>()
1428 try:
-> 1429 fontManager = pickle_load(_fmcache)
1430 if (not hasattr(fontManager, '_version') or

/usr/lib64/python3.6/site-packages/matplotlib/font_manager.py in pickle_load(filename)
964 """
--> 965 with open(filename, 'rb') as fh:
966 data = pickle.load(fh)

FileNotFoundError: [Errno 2] No such file or directory: '/home/javad/.cache/matplotlib/fontList.py3k.cache'

During handling of the above exception, another exception occurred:

UnicodeDecodeErrorTraceback (most recent call last)
<ipython-input-3-a371ea114746> in <module>()
----> 1 from matplotlib import pyplot

/usr/lib64/python3.6/site-packages/matplotlib/pyplot.py in <module>()
27 from cycler import cycler
28 import matplotlib
---> 29 import matplotlib.colorbar
30 from matplotlib import style
31 from matplotlib import _pylab_helpers, interactive

/usr/lib64/python3.6/site-packages/matplotlib/colorbar.py in <module>()
34 import matplotlib.collections as collections
35 import matplotlib.colors as colors
---> 36 import matplotlib.contour as contour
37 import matplotlib.cm as cm
38 import matplotlib.gridspec as gridspec

/usr/lib64/python3.6/site-packages/matplotlib/contour.py in <module>()
20 import matplotlib.colors as colors
21 import matplotlib.collections as mcoll
---> 22 import matplotlib.font_manager as font_manager
23 import matplotlib.text as text
24 import matplotlib.cbook as cbook

/usr/lib64/python3.6/site-packages/matplotlib/font_manager.py in <module>()
1437 raise
1438 except:
-> 1439 _rebuild()
1440 else:
1441 _rebuild()

/usr/lib64/python3.6/site-packages/matplotlib/font_manager.py in _rebuild()
1416 global fontManager
1417
-> 1418 fontManager = FontManager()
1419
1420 if _fmcache:

/usr/lib64/python3.6/site-packages/matplotlib/font_manager.py in __init__(self, size, weight)
1070 self.afmfiles = findSystemFonts(paths, fontext='afm') + \
1071 findSystemFonts(fontext='afm')
-> 1072 self.afmlist = createFontList(self.afmfiles, fontext='afm')
1073 if len(self.afmfiles):
1074 self.defaultFont['afm'] = self.afmfiles[0]

/usr/lib64/python3.6/site-packages/matplotlib/font_manager.py in createFontList(fontfiles, fontext)
581 try:
582 try:
--> 583 font = afm.AFM(fh)
584 finally:
585 fh.close()

/usr/lib64/python3.6/site-packages/matplotlib/afm.py in __init__(self, fh)
347 """
348 (dhead, dcmetrics_ascii, dcmetrics_name, dkernpairs, dcomposite) = \
--> 349 parse_afm(fh)
350 self._header = dhead
351 self._kern = dkernpairs

/usr/lib64/python3.6/site-packages/matplotlib/afm.py in parse_afm(fh)
335 _sanity_check(fh)
336 dhead = _parse_header(fh)
--> 337 dcmetrics_ascii, dcmetrics_name = _parse_char_metrics(fh)
338 doptional = _parse_optional(fh)
339 return dhead, dcmetrics_ascii, dcmetrics_name, doptional[0], doptional[1]

/usr/lib64/python3.6/site-packages/matplotlib/afm.py in _parse_char_metrics(fh)
196 if not line:
197 break
--> 198 line = line.rstrip().decode('ascii') # Convert from byte-literal
199 if line.startswith('EndCharMetrics'):
200 return ascii_d, name_d

UnicodeDecodeError: 'ascii' codec can't decode byte 0x8e in position 20: ordinal not in range(128)

Expected outcome

using %matplotlib magic in jupyter notebook also produces the same error.

Matplotlib version

Operating System: Fedora 26, 64bit

Matplotlib Version: 2.0.0-2

Python Version: 2.7 / 3.6

Jupyter Version (if applicable): 4.1.0

Other Libraries:

Issue 2:
I posted in #3487 and following the suggestion of @tacaswell , I create a separate issue, for easier bug tracking:

Since upgrading to 1.4.0, I get the same exception.

I'm on Mac, Mavericks, latest version. anaconda bundle.

I'm not even sure it's about matplotlib, but it crashes when it gets to font_manager.

This is the relevant output for the exception:

---> 18 import matplotlib.pyplot as plt
19
20 from copy import deepcopy

/Users/ifmichael/anaconda/lib/python2.7/site-packages/matplotlib/pyplot.py in <module>()
25
26 import matplotlib
---> 27 import matplotlib.colorbar
28 from matplotlib import style
29 from matplotlib import _pylab_helpers, interactive

/Users/ifmichael/anaconda/lib/python2.7/site-packages/matplotlib/colorbar.py in <module>()
32 import matplotlib.artist as martist
33 import matplotlib.cbook as cbook
---> 34 import matplotlib.collections as collections
35 import matplotlib.colors as colors
36 import matplotlib.contour as contour

/Users/ifmichael/anaconda/lib/python2.7/site-packages/matplotlib/collections.py in <module>()
25 import matplotlib.artist as artist
26 from matplotlib.artist import allow_rasterization
---> 27 import matplotlib.backend_bases as backend_bases
28 import matplotlib.path as mpath
29 from matplotlib import _path

/Users/ifmichael/anaconda/lib/python2.7/site-packages/matplotlib/backend_bases.py in <module>()
54
55 import matplotlib.tight_bbox as tight_bbox
---> 56 import matplotlib.textpath as textpath
57 from matplotlib.path import Path
58 from matplotlib.cbook import mplDeprecation

/Users/ifmichael/anaconda/lib/python2.7/site-packages/matplotlib/textpath.py in <module>()
17 from matplotlib.path import Path
18 from matplotlib import rcParams
---> 19 import matplotlib.font_manager as font_manager
20 from matplotlib.ft2font import FT2Font, KERNING_DEFAULT, LOAD_NO_HINTING
21 from matplotlib.ft2font import LOAD_TARGET_LIGHT

/Users/ifmichael/anaconda/lib/python2.7/site-packages/matplotlib/font_manager.py in <module>()
1410 verbose.report("Using fontManager instance from %s" % _fmcache)
1411 except:
-> 1412 _rebuild()
1413 else:
1414 _rebuild()

/Users/ifmichael/anaconda/lib/python2.7/site-packages/matplotlib/font_manager.py in _rebuild()
1395 def _rebuild():
1396 global fontManager
-> 1397 fontManager = FontManager()
1398 if _fmcache:
1399 pickle_dump(fontManager, _fmcache)

/Users/ifmichael/anaconda/lib/python2.7/site-packages/matplotlib/font_manager.py in __init__(self, size, weight)
1035 # Load TrueType fonts and create font dictionary.
1036
-> 1037 self.ttffiles = findSystemFonts(paths) + findSystemFonts()
1038 self.defaultFamily = {
1039 'ttf': 'Bitstream Vera Sans',

/Users/ifmichael/anaconda/lib/python2.7/site-packages/matplotlib/font_manager.py in findSystemFonts(fontpaths, fontext)
320 fontfiles[f] = 1
321
--> 322 for f in get_fontconfig_fonts(fontext):
323 fontfiles[f] = 1
324

/Users/ifmichael/anaconda/lib/python2.7/site-packages/matplotlib/font_manager.py in get_fontconfig_fonts(fontext)
272 pipe = subprocess.Popen(['fc-list', '--format=%{file}\\n'],
273 stdout=subprocess.PIPE,
--> 274 stderr=subprocess.PIPE)
275 output = pipe.communicate()[0]
276 except (OSError, IOError):

/Users/ifmichael/anaconda/lib/python2.7/subprocess.pyc in __init__(self, args, bufsize, executable, stdin, stdout, stderr, preexec_fn, close_fds, shell, cwd, env, universal_newlines, startupinfo, creationflags)
708 p2cread, p2cwrite,
709 c2pread, c2pwrite,
--> 710 errread, errwrite)
711 except Exception:
712 # Preserve original exception in case os.close raises.

/Users/ifmichael/anaconda/lib/python2.7/subprocess.pyc in _execute_child(self, args, executable, preexec_fn, close_fds, cwd, env, universal_newlines, startupinfo, creationflags, shell, to_close, p2cread, p2cwrite, c2pread, c2pwrite, errread, errwrite)
1325 raise
1326 child_exception = pickle.loads(data)
-> 1327 raise child_exception
1328
1329

UnicodeDecodeError: 'ascii' codec can't decode byte 0xe2 in position 0: ordinal not in range(128)

Right now I downgraded to 1.3.1, and everything got back to normal.