bpo-28411: Isolate PyInterpreterState.modules (#3575)

A bunch of code currently uses PyInterpreterState.modules directly instead of PyImport_GetModuleDict(). This complicates efforts to make changes relative to sys.modules. This patch switches to using PyImport_GetModuleDict() uniformly. Also, a number of related uses of sys.modules are updated for uniformity for the same reason.

Note that this code was already reviewed and merged as part of #1638. I reverted that and am now splitting it up into more focused parts.

1 files changed, 4 insertions, 3 deletions

diff --git a/Python/sysmodule.c b/Python/sysmodule.c
index 9e13d49..d463683 100644
--- a/Python/sysmodule.c
+++ b/Python/sysmodule.c
@@ -162,8 +162,9 @@ static PyObject *
 sys_displayhook(PyObject *self, PyObject *o)
 {
     PyObject *outf;
-    PyInterpreterState *interp = PyThreadState_GET()->interp;
-    PyObject *modules = interp->modules;
+    PyObject *modules = PyImport_GetModuleDict();
+    if (modules == NULL)
+        return NULL;
     PyObject *builtins;
     static PyObject *newline = NULL;
     int err;
@@ -1949,7 +1950,7 @@ _PySys_BeginInit(void)
     PyObject *m, *sysdict, *version_info;
     int res;
 
-    m = PyModule_Create(&sysmodule);
+    m = _PyModule_CreateInitialized(&sysmodule, PYTHON_API_VERSION);
     if (m == NULL)
         return NULL;
     sysdict = PyModule_GetDict(m);