Fix test that fails on i686:

https://bitbucket.org/cffi/cffi/issues/382

This is a squashed version of these commits:
https://bitbucket.org/cffi/cffi/commits/ef09637b2314
https://bitbucket.org/cffi/cffi/commits/7a76a3815340

diff -r 99940f1f5402 testing/cffi0/test_function.py
--- a/testing/cffi0/test_function.py	Tue Feb 27 21:18:33 2018 +0100
+++ b/testing/cffi0/test_function.py	Sun Nov 11 16:26:23 2018 +0100
@@ -45,14 +45,14 @@
         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):
able>
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<tr><td><span title='2016-09-14 22:04:50 +0300'>2016-09-14</span></td><td><a href='/guix/commit/gnu/packages/links.scm?id=6ea541e016706568538c9ca842211c74a70927b8'>gnu: links: Use 'modify-phases'.</a><span class='msg-avail'>...</span></td><td>Efraim Flashner</td></tr>
<tr><td><span title='2016-09-14 22:02:40 +0300'>2016-09-14</span></td><td><a href='/guix/commit/gnu/packages/links.scm?id=7ddacf88ef893856b920c52c65bc81689fc277b8'>gnu: links: Update to 2.13.</a><span class='msg-avail'>...</span></td><td>Efraim Flashner</td></tr>
<tr><td><span title='2015-11-02 10:50:08 +0200'>2015-11-02</span></td><td><a href='/guix/commit/gnu/packages/links.scm?id=a83adbf681b7f0ce68eaff2b55f17ea5563f66bc'>gnu: links: Build with libevent.</a><span class='msg-avail'>...</span></td><td>Efraim Flashner</td></tr>
<tr><td><span title='2015-11-02 10:46:56 +0200'>2015-11-02</span></td><td><a href='/guix/commit/gnu/packages/links.scm?id=cb7fed9285e6eb7b9b4a2dd7a6c5b553de86771d'>gnu: links: Update to 2.12.</a><span class='msg-avail'>...</span></td><td>Efraim Flashner</td></tr>
<tr><td><span title='2015-07-05 18:27:24 +0200'>2015-07-05</span></td><td><a href='/guix/commit/gnu/packages/links.scm?id=cc2b77dfc715c2133bd0c9e318bd7dc90bfedece'>gnu: Move content of openssl module into tls module.</a><span class='msg-avail'>...</span></td><td>Andreas Enge</td></tr>
<tr><td><span title='2014-09-23 18:52:29 -0400'>2014-09-23</span></td><td><a href='/guix/commit/gnu/packages/links.scm?id=b5b73a8269eb46064d8c85c4ba189b6914ac06b6'>Use #:prefix instead of #:renamer with 'symbol-prefix-proc'.</a><span class='msg-avail'>...</span></td><td>Mark H Weaver</td></tr>