New warnings: warning: unused function 'ensure_shared_on_read' [-Wunused-function]

[Eclips4]

Bug report

Bug description:

Popped up during the build (./configure --with-pydebug && make -j):

Objects/dictobject.c:1233:1: warning: unused function 'ensure_shared_on_read' [-Wunused-function]
ensure_shared_on_read(PyDictObject *mp)
^
In file included from Objects/obmalloc.c:16:
In file included from Objects/mimalloc/static.c:23:
Objects/mimalloc/alloc.c:77:5: warning: static function 'mi_debug_fill' is used in an inline function with external linkage [-Wstatic-in-inline]
mi_debug_fill(page, block, MI_DEBUG_UNINIT, mi_page_usable_block_size(page));
^
Objects/mimalloc/alloc.c:30:13: note: 'mi_debug_fill' declared here
static void mi_debug_fill(mi_page_t* page, mi_block_t* block, int c, size_t size) {
...
Objects/dictobject.c:5032:9: warning: logical not is only applied to the left hand side of this comparison [-Wlogical-not-parentheses]
    if (!dictiter_iternext_threadsafe(d, self, &value, NULL) == 0) {
        ^                                                    ~~
Objects/dictobject.c:5032:9: note: add parentheses after the '!' to evaluate the comparison first
    if (!dictiter_iternext_threadsafe(d, self, &value, NULL) == 0) {
        ^
         (                                                       )
Objects/dictobject.c:5032:9: note: add parentheses around left hand side expression to silence this warning
    if (!dictiter_iternext_threadsafe(d, self, &value, NULL) == 0) {
        ^
        (                                                   )
Objects/dictobject.c:5155:9: warning: logical not is only applied to the left hand side of this comparison [-Wlogical-not-parentheses]
    if (!dictiter_iternext_threadsafe(d, self, NULL, &value) == 0) {
        ^                                                    ~~
Objects/dictobject.c:5155:9: note: add parentheses after the '!' to evaluate the comparison first
    if (!dictiter_iternext_threadsafe(d, self, NULL, &value) == 0) {
        ^
         (                                                       )
Objects/dictobject.c:5155:9: note: add parentheses around left hand side expression to silence this warning
    if (!dictiter_iternext_threadsafe(d, self, NULL, &value) == 0) {
        ^

CPython versions tested on:

CPython main branch

Operating systems tested on:

macOS

Linked PRs

• gh-116029: Fix unused function warning on macOS #116340

[colesbury]

I think both of these bugs have been fixed now:

• gh-115491: Fix Clang compiler warning #116153
• gh-112075: Remove compiler warning from apple clang #115855

[sobolevn]

Since this function looks like this:

static inline void
ensure_shared_on_read(PyDictObject *mp)
{
#ifdef Py_GIL_DISABLED
    if (!_Py_IsOwnedByCurrentThread((PyObject *)mp) && !IS_DICT_SHARED(mp)) {
        // The first time we access a dict from a non-owning thread we mark it
        // as shared. This ensures that a concurrent resize operation will
        // delay freeing the old keys or values using QSBR, which is necessary
        // to safely allow concurrent reads without locking...
        Py_BEGIN_CRITICAL_SECTION(mp);
        if (!IS_DICT_SHARED(mp)) {
            SET_DICT_SHARED(mp);
        }
        Py_END_CRITICAL_SECTION();
    }
#endif
}

I am going to cc @colesbury

[sobolevn]

@colesbury it was fast 😆

I still see this on the latest main:

Objects/dictobject.c:1242:1: warning: unused function 'ensure_shared_on_read' [-Wunused-function]
ensure_shared_on_read(PyDictObject *mp)
^