              try:
                  check_include_file(get_include_dirs(), 'ft2build.h', 'freetype')
              except CheckFailed:
-                 check_include_file(get_include_dirs(), 'freetype2\\ft2build.h', 'freetype')
+                 check_include_file(get_include_dirs(), os.path.join('freetype2', 'ft2build.h'), 'freetype')
              return 'Using unknown version found on system.'
  
 -        status, output = getstatusoutput("freetype-config --ftversion")

         if status == 0:
             version = output
         else:
@@ -1543,7 +1562,7 @@
         return ext
 
     def add_flags(self, ext):

--- matplotlib-2.2.4/setupext.py.orig	2019-02-26 05:07:47.000000000 +0300
+++ matplotlib-2.2.4/setupext.py	2019-02-28 11:16:25.082326600 +0300
@@ -57,6 +57,8 @@
 
 PY3min = (sys.version_info[0] >= 3)
 
