Description: Use lround instead of sin in void-returning test
  sin returns float, but overriding it to return void breaks x87 calling
  conventions and causes the *nest* float-using test to fail.  Use lround
  instead to avoid this.
Author: Adam Conrad <adconrad@ubuntu.com>
Bug: https://bitbucket.org/cffi/cffi/issues/382/test_sin_no_return_value-violates-calling
Last-Update: 2018-09-04

--- python-cffi-1.11.5.orig/testing/cffi0/test_function.py
+++ python-cffi-1.11.5/testing/cffi0/test_function.py
@@ -45,14 +45,14 @@ class TestFunction(object):
         assert x != math.sin(1.23)    # rounding effects
         assert abs(x - math.sin(1.23)) < 1E-6
 
-    def test_sin_no_return_value(self):
+    def test_lround_no_return_value(self):
         # check that 'void'-returning functions work too
         ffi = FFI(backend=self.Backend())
         ffi.cdef("""
-            void sin(double x);
+            void lround(double x);
         """)
         m = ffi.dlopen(lib_m)
-        x = m.sin(1.23)
+        x = m.lround(1.23)
         assert x is None
 
     def test_dlopen_filename(self):
