.

bigfile/virtmem.c

@@ -100,6 +100,16 @@ void virt_unlock()
 
 void virt_lock_hookgil(const VirtGilHooks *gilhooks)
 {
+    // FIXME we hit vvv assert for real because `import bigfile,
+    // wendelin.bigfile` import bigfile/__init__.py twice and that in turn
+    // imports bigfile/_bigfile.so twice. However Python loads _bigfile.so DSO
+    // only once - oops. The bug happens in practice when running tests via
+    // pytest under python3.
+    //
+    // XXX temp hack to workaround that bug for now.
+    if (virtmem_gilhooks == gilhooks)
+	    virtmem_gilhooks = NULL;
+
     BUG_ON(virtmem_gilhooks);       /* prevent registering multiple times */
     virtmem_gilhooks = gilhooks;
 }

setup.py

@@ -249,6 +249,8 @@ setup(
                    'psutil',    # demo_zbigarray
 
                    'pygolang >= 0.0.0.dev4',  # wcfs
+
+                   'zodbtools', # XXX clarify whether we can always require it (check lib/zodb.py)
                   ],
 
     extras_require = {

tox.ini

@@ -10,6 +10,9 @@ deps    =
     # why tox does not get it from extras_require['test'] ?
     pytest
 
+    # XXX temp hack
+    cython
+
     # latest ZODB from 3 series
     ZODB3:  ZODB3 >=3.10, <3.11dev
     ZODB3:  transaction <2.0dev