Revert "Merge branch 'petrmitrichev-remove-function-local-statics'"

This reverts commit b8ed7759d5, reversing
changes made to 6f2399e86d.

CHANGES.current

@@ -7,11 +7,6 @@ the issue number to the end of the URL: https://github.com/swig/swig/issues/
 Version 4.0.0 (in progress)
 ===========================
 
-2018-06-30: petrmitrichev
-            [Python] #1275 #1279 Remove function-local statics that call Python code
-            in order to avoid deadlocks with multi-threaded usage. These are now
-            file scope static variables and are initialized during module initialization.
-
 2018-06-15: wsfulton
             [Python] Fix seg fault using Python 2 when passing a Python string, containing
             invalid utf-8 content, to a wstring or wchar * parameter. A TypeError is thrown instead, eg:

Lib/python/pyinit.swg

@@ -379,14 +379,6 @@ SWIG_init(void) {
   assert(metatype);
 #endif
 
-#ifdef SWIG_PYTHON_BUILD_NONE
-  SWIG_Py_None_global = Py_BuildValue("");
-  Py_DECREF(SWIG_Py_None_global);
-#endif
-
-  SWIG_This_global = SWIG_Python_str_FromChar("this");
-  SWIG_Python_TypeCache_global = PyDict_New();
-
   /* Fix SwigMethods to carry the callback ptrs when needed */
   SWIG_Python_FixMethods(SwigMethods, swig_const_table, swig_types, swig_type_initial);
 
@@ -437,11 +429,8 @@ SWIG_init(void) {
     SwigPyBuiltin_AddPublicSymbol(public_interface, SwigMethods[i].ml_name);
   for (i = 0; swig_const_table[i].name != 0; ++i)
     SwigPyBuiltin_AddPublicSymbol(public_interface, swig_const_table[i].name);
-#else
-  SwigPyObject_type_global = SwigPyObject_TypeOnce();
 #endif
 
-  SwigPyPacked_type_global = SwigPyPacked_TypeOnce();
   SWIG_InstallConstants(d,swig_const_table);
 %}
 

Lib/python/pyrun.swg

@@ -210,6 +210,16 @@ SWIG_Python_UnpackTuple(PyObject *args, const char *name, Py_ssize_t min, Py_ssi
 /* A functor is a function object with one single object argument */
 #define SWIG_Python_CallFunctor(functor, obj)	        PyObject_CallFunction(functor, (char*)"O", obj);
 
+/*
+  Helper for static pointer initialization for both C and C++ code, for example
+  static PyObject *SWIG_STATIC_POINTER(MyVar) = NewSomething(...);
+*/
+#ifdef __cplusplus
+#define SWIG_STATIC_POINTER(var)  var
+#else
+#define SWIG_STATIC_POINTER(var)  var = 0; if (!var) var
+#endif
+
 /* -----------------------------------------------------------------------------
  * Pointer declarations
  * ----------------------------------------------------------------------------- */
@@ -241,20 +251,26 @@ extern "C" {
 #   undef Py_None
 #   define Py_None SWIG_Py_None()
 #  endif
-
-static PyObject *SWIG_Py_None_global = 0;
-
-SWIGRUNTIME PyObject *
-SWIG_Py_None(void) {
-  assert(SWIG_Py_None_global);
-  return SWIG_Py_None_global;
+SWIGRUNTIMEINLINE PyObject * 
+_SWIG_Py_None(void)
+{
+  PyObject *none = Py_BuildValue("");
+  Py_DECREF(none);
+  return none;
+}
+SWIGRUNTIME PyObject * 
+SWIG_Py_None(void)
+{
+  static PyObject *SWIG_STATIC_POINTER(none) = _SWIG_Py_None();
+  return none;
 }
 #endif
 
 /* The python void return value */
 
 SWIGRUNTIMEINLINE PyObject * 
-SWIG_Py_Void(void) {
+SWIG_Py_Void(void)
+{
   PyObject *none = Py_None;
   Py_INCREF(none);
   return none;
@@ -463,7 +479,6 @@ SWIGRUNTIME PyTypeObject* SwigPyObject_TypeOnce(void);
 
 #ifdef SWIGPYTHON_BUILTIN
 static swig_type_info *SwigPyObject_stype = 0;
-
 SWIGRUNTIME PyTypeObject*
 SwigPyObject_type(void) {
     SwigPyClientData *cd;
@@ -474,12 +489,10 @@ SwigPyObject_type(void) {
     return cd->pytype;
 }
 #else
-static PyTypeObject *SwigPyObject_type_global = 0;
-
 SWIGRUNTIME PyTypeObject*
 SwigPyObject_type(void) {
-  assert(SwigPyObject_type_global);
-  return SwigPyObject_type_global;
+  static PyTypeObject *SWIG_STATIC_POINTER(type) = SwigPyObject_TypeOnce();
+  return type;
 }
 #endif
 
@@ -823,12 +836,10 @@ SwigPyPacked_compare(SwigPyPacked *v, SwigPyPacked *w)
 
 SWIGRUNTIME PyTypeObject* SwigPyPacked_TypeOnce(void);
 
-static PyTypeObject* SwigPyPacked_type_global = 0;
-
 SWIGRUNTIME PyTypeObject*
 SwigPyPacked_type(void) {
-  assert(SwigPyPacked_type_global);
-  return SwigPyPacked_type_global;
+  static PyTypeObject *SWIG_STATIC_POINTER(type) = SwigPyPacked_TypeOnce();
+  return type;
 }
 
 SWIGRUNTIMEINLINE int
@@ -965,12 +976,20 @@ SwigPyPacked_UnpackData(PyObject *obj, void *ptr, size_t size)
  * pointers/data manipulation
  * ----------------------------------------------------------------------------- */
 
-static PyObject *SWIG_This_global = NULL;
+SWIGRUNTIMEINLINE PyObject *
+_SWIG_This(void)
+{
+    return SWIG_Python_str_FromChar("this");
+}
+
+static PyObject *swig_this = NULL;
 
 SWIGRUNTIME PyObject *
-SWIG_This(void) {
-  assert(SWIG_This_global);
-  return SWIG_This_global;
+SWIG_This(void)
+{
+  if (swig_this == NULL)
+    swig_this = _SWIG_This();
+  return swig_this;
 }
 
 /* #define SWIG_PYTHON_SLOW_GETSET_THIS */
@@ -1399,7 +1418,7 @@ SWIG_Python_DestroyModule(PyObject *obj)
     }
   }
   Py_DECREF(SWIG_This());
-  SWIG_This_global = NULL;
+  swig_this = NULL;
 }
 
 SWIGRUNTIME void
@@ -1419,13 +1438,11 @@ SWIG_Python_SetModule(swig_module_info *swig_module) {
   }
 }
 
-static PyObject *SWIG_Python_TypeCache_global = 0;
-
 /* The python cached type query */
 SWIGRUNTIME PyObject *
 SWIG_Python_TypeCache(void) {
-  assert(SWIG_Python_TypeCache_global);
-  return SWIG_Python_TypeCache_global;
+  static PyObject *SWIG_STATIC_POINTER(cache) = PyDict_New();
+  return cache;
 }
 
 SWIGRUNTIME swig_type_info *