bpo-39487: Merge duplicated _Py_IDENTIFIER identifiers in C code (GH-18254)

Moving repetitive `_Py_IDENTIFIER` instances to a global location helps identify them more easily in regards to sub-interpreter support.

Python/_warnings.c

@@ -24,6 +24,8 @@ typedef struct _warnings_runtime_state WarningsState;
 /* Forward declaration of the _warnings module definition. */
 static struct PyModuleDef warningsmodule;
 
+_Py_IDENTIFIER(__name__);
+
 /* Given a module object, get its per-module state. */
 static WarningsState *
 _Warnings_GetState()
@@ -484,7 +486,6 @@ show_warning(PyObject *filename, int lineno, PyObject *text,
     PyObject *f_stderr;
     PyObject *name;
     char lineno_str[128];
-    _Py_IDENTIFIER(__name__);
 
     PyOS_snprintf(lineno_str, sizeof(lineno_str), ":%d: ", lineno);
 
@@ -818,7 +819,6 @@ setup_context(Py_ssize_t stack_level, PyObject **filename, int *lineno,
               PyObject **module, PyObject **registry)
 {
     _Py_IDENTIFIER(__warningregistry__);
-    _Py_IDENTIFIER(__name__);
     PyObject *globals;
 
     /* Setup globals, filename and lineno. */
@@ -969,7 +969,6 @@ get_source_line(PyObject *module_globals, int lineno)
 {
     _Py_IDENTIFIER(get_source);
     _Py_IDENTIFIER(__loader__);
-    _Py_IDENTIFIER(__name__);
     PyObject *loader;
     PyObject *module_name;
     PyObject *get_source;

Python/ceval.c

@@ -39,6 +39,7 @@
 #  error "ceval.c must be build with Py_BUILD_CORE define for best performance"
 #endif
 
+_Py_IDENTIFIER(__name__);
 
 /* Forward declarations */
 Py_LOCAL_INLINE(PyObject *) call_function(
@@ -5032,7 +5033,6 @@ static PyObject *
 import_from(PyThreadState *tstate, PyObject *v, PyObject *name)
 {
     PyObject *x;
-    _Py_IDENTIFIER(__name__);
     PyObject *fullmodname, *pkgname, *pkgpath, *pkgname_or_unknown, *errmsg;
 
     if (_PyObject_LookupAttr(v, name, &x) != 0) {
@@ -5108,7 +5108,6 @@ import_all_from(PyThreadState *tstate, PyObject *locals, PyObject *v)
 {
     _Py_IDENTIFIER(__all__);
     _Py_IDENTIFIER(__dict__);
-    _Py_IDENTIFIER(__name__);
     PyObject *all, *dict, *name, *value;
     int skip_leading_underscores = 0;
     int pos, err;

Python/errors.c

@@ -24,11 +24,11 @@ extern char *strerror(int);
 extern "C" {
 #endif
 
+_Py_IDENTIFIER(__module__);
 _Py_IDENTIFIER(builtins);
 _Py_IDENTIFIER(stderr);
 _Py_IDENTIFIER(flush);
 
-
 /* Forward declarations */
 static PyObject *
 _PyErr_FormatV(PyThreadState *tstate, PyObject *exception,
@@ -1009,7 +1009,6 @@ PyObject *
 PyErr_NewException(const char *name, PyObject *base, PyObject *dict)
 {
     PyThreadState *tstate = _PyThreadState_GET();
-    _Py_IDENTIFIER(__module__);
     PyObject *modulename = NULL;
     PyObject *classname = NULL;
     PyObject *mydict = NULL;
@@ -1235,7 +1234,6 @@ write_unraisable_exc_file(PyThreadState *tstate, PyObject *exc_type,
         }
     }
 
-    _Py_IDENTIFIER(__module__);
     PyObject *moduleName = _PyObject_GetAttrId(exc_type, &PyId___module__);
     if (moduleName == NULL || !PyUnicode_Check(moduleName)) {
         Py_XDECREF(moduleName);

Python/import.c

@@ -39,6 +39,9 @@ extern struct _inittab _PyImport_Inittab[];
 struct _inittab *PyImport_Inittab = _PyImport_Inittab;
 static struct _inittab *inittab_copy = NULL;
 
+_Py_IDENTIFIER(__path__);
+_Py_IDENTIFIER(__spec__);
+
 /*[clinic input]
 module _imp
 [clinic start generated code]*/
@@ -383,7 +386,6 @@ import_ensure_initialized(PyThreadState *tstate, PyObject *mod, PyObject *name)
     PyInterpreterState *interp = tstate->interp;
     PyObject *spec;
 
-    _Py_IDENTIFIER(__spec__);
     _Py_IDENTIFIER(_lock_unlock_module);
 
     /* Optimization: only call _bootstrap._lock_unlock_module() if
@@ -1566,9 +1568,7 @@ done:
 static PyObject *
 resolve_name(PyThreadState *tstate, PyObject *name, PyObject *globals, int level)
 {
-    _Py_IDENTIFIER(__spec__);
     _Py_IDENTIFIER(__package__);
-    _Py_IDENTIFIER(__path__);
     _Py_IDENTIFIER(__name__);
     _Py_IDENTIFIER(parent);
     PyObject *abs_name;
@@ -1930,7 +1930,6 @@ PyImport_ImportModuleLevelObject(PyObject *name, PyObject *globals,
         }
     }
     else {
-        _Py_IDENTIFIER(__path__);
         PyObject *path;
         if (_PyObject_LookupAttrId(mod, &PyId___path__, &path) < 0) {
             goto error;