py/objmodule: Workaround for MSVC with no module delegation.

jimmo · jimmo · commit e6926d60219d · 2023-06-08T17:54:24.000+10:00
When compiling mpy-cross, there is no `sys` module, and so there will
be no entries in the `mp_builtin_module_delegation_table`.

MSVC doesn't like this, so instead pretend as if the feature isn't
enabled at all.

Signed-off-by: Jim Mussared &lt;jim.mussared@gmail.com&gt;
diff --git a/py/makemoduledefs.py b/py/makemoduledefs.py
@@ -103,6 +103,9 @@ def generate_module_table_header(modules):
 
 
 def generate_module_delegations(delegations):
+    if not delegations:
+        return
+
     print("\n#define MICROPY_MODULE_DELEGATIONS \\")
     for obj_module, fun_name in delegations:
         print(
diff --git a/py/objmodule.c b/py/objmodule.c
@@ -230,7 +230,7 @@ mp_obj_t mp_module_get_builtin(qstr module_name, bool extensible) {
 }
 
 STATIC void module_attr_try_delegation(mp_obj_t self_in, qstr attr, mp_obj_t *dest) {
-    #if MICROPY_MODULE_ATTR_DELEGATION
+    #if MICROPY_MODULE_ATTR_DELEGATION && defined(MICROPY_MODULE_DELEGATIONS)
     // Delegate lookup to a module's custom attr method.
     size_t n = MP_ARRAY_SIZE(mp_builtin_module_delegation_table);
     for (size_t i = 0; i < n; ++i) {

Original file line number	Diff line number	Diff line change
`@@ -230,7 +230,7 @@ mp_obj_t mp_module_get_builtin(qstr module_name, bool extensible) {`
`230`	`230`	`}`
`231`	`231`
`232`	`232`	`STATIC void module_attr_try_delegation(mp_obj_t self_in, qstr attr, mp_obj_t *dest) {`
`233`		`- #if MICROPY_MODULE_ATTR_DELEGATION`
	`233`	`+ #if MICROPY_MODULE_ATTR_DELEGATION && defined(MICROPY_MODULE_DELEGATIONS)`
`234`	`234`	`// Delegate lookup to a module's custom attr method.`
`235`	`235`	`size_t n = MP_ARRAY_SIZE(mp_builtin_module_delegation_table);`
`236`	`236`	`for (size_t i = 0; i < n; ++i) {`