Force Cython rebuild of c files

python-pyopengl.spec

@@ -93,6 +93,13 @@ Provides:       python3-PyOpenGL-Tk = %{version}-%{release}
 
 
 %build
+# Delete all Cython generated .c files to force a rebuild
+pushd %{srcname}-accelerate-%{version}
+for f in *.pyx ; do
+    rm -f "${f%.pyx}.c"
+done
+popd
+
 for dir in %{srcname}-%{version} %{srcname}-accelerate-%{version} ; do
     pushd $dir
     %py2_build
@@ -154,6 +161,7 @@ popd
 * Tue Jun 26 2018 Jonathan Underwood <Jonathan G. Underwood@gmail.com> - 3.1.1a1-12
 - Add BuildRequires for python{2,3}-Cython
 - Remove uneeded Provides/Obsoletes
+- Force Cython rebuild of c files
 
 * Tue Jun 19 2018 Miro Hrončok <mhroncok@redhat.com> - 3.1.1a1-11
 - Rebuilt for Python 3.7