MNT: move sys.flags.optimize cache to global data struct

Author: ngoldbaum

numpy/_core/src/multiarray/compiled_base.c

@@ -1414,14 +1414,7 @@ arr_add_docstring(PyObject *NPY_UNUSED(dummy), PyObject *const *args, Py_ssize_t
 
     /* Don't add docstrings */
 #if PY_VERSION_HEX > 0x030b0000
-    static long optimize = -1000;
-    if (optimize < 0) {
-        PyObject *flags = PySys_GetObject("flags");  /* borrowed object */
-        PyObject *level = PyObject_GetAttrString(flags, "optimize");
-        optimize = PyLong_AsLong(level);
-        Py_DECREF(level);
-    }
-    if (optimize > 1) {
+    if (npy_ma_global_data->optimize > 1) {
 #else
     if (Py_OptimizeFlag > 1) {
 #endif

numpy/_core/src/multiarray/multiarraymodule.c

@@ -4965,10 +4965,20 @@ initialize_static_globals(void)
         numpy_warn_if_no_mem_policy = 0;
     }
 
+    PyObject *flags = PySys_GetObject("flags");  /* borrowed object */
+    if (flags == NULL) {
+        PyErr_SetString(PyExc_AttributeError, "cannot get sys.flags");
+        return -1;
+    }
+    PyObject *level = PyObject_GetAttrString(flags, "optimize");
+    if (level == NULL) {
+        return -1;
+    }
+    npy_ma_global_data->optimize = PyLong_AsLong(level);
+    Py_DECREF(level);
     return 0;
 }
 
-
 static struct PyModuleDef moduledef = {
         PyModuleDef_HEAD_INIT,
         "_multiarray_umath",

numpy/_core/src/multiarray/multiarraymodule.h

@@ -60,6 +60,12 @@ typedef struct npy_ma_global_data_struct {
     PyObject *os_PathLike;
     PyObject *os_fspath;
 
+    /*
+     * stores sys.flags.optimize as a long, which is used in the add_docstring
+     * implementation
+     */
+    long optimize;
+
     /*
      * Used for CPU feature detection and dispatch
      *