Switch AssociatedMiniTable to a fn from an associated const.
PiperOrigin-RevId: 663324366
diff --git a/rust/upb/associated_mini_table.rs b/rust/upb/associated_mini_table.rs
index 382d9a6..e8db8fe 100644
--- a/rust/upb/associated_mini_table.rs
+++ b/rust/upb/associated_mini_table.rs
@@ -16,15 +16,20 @@
/// passed in as a parameter, which is referred to as 'the associated MiniTable
/// for the upb_Message instance' in safety comments.
///
-/// This trait is a way to statically associate a MiniTable with Rust types
+/// This trait is a way to associate a MiniTable with Rust types
/// which hold upb_Message* to simplify ensuring the upb C invariants
/// are maintained.
///
-/// SAFETY:
-/// - The MiniTable pointer must be from Protobuf code generation and follow the
-/// corresponding invariants associated with upb's C API (the pointer should
-/// always have the same non-null value, the underlying pointee should never
-/// be modified and should have 'static lifetime).
-pub unsafe trait AssociatedMiniTable {
- const MINI_TABLE: *const upb_MiniTable;
+/// Note that this would prefer to be a `const MINI_TABLE: *const upb_MiniTable`
+/// to statically associate a single MiniTable, but as long as the MiniTable is
+/// an extern "C" we cannot do that without the unstable `const_refs_to_static`.
+/// After that feature is stabilized (or if we move the MiniTable generation to
+/// .rs) this will be switched.
+pub trait AssociatedMiniTable {
+ /// SAFETY:
+ /// - The MiniTable pointer must be from Protobuf code generation and follow
+ /// the corresponding invariants associated with upb's C API (the pointer
+ /// should always have the same non-null value, the underlying pointee
+ /// should never be modified and should have 'static lifetime).
+ unsafe fn mini_table() -> *const upb_MiniTable;
}
diff --git a/src/google/protobuf/compiler/rust/accessors/repeated_field.cc b/src/google/protobuf/compiler/rust/accessors/repeated_field.cc
index a8f6e2b..797ac8f 100644
--- a/src/google/protobuf/compiler/rust/accessors/repeated_field.cc
+++ b/src/google/protobuf/compiler/rust/accessors/repeated_field.cc
@@ -114,7 +114,7 @@
pub fn set_$raw_field_name$(&mut self, src: impl $pb$::IntoProxied<$pb$::Repeated<$RsType$>>) {
let minitable_field = unsafe {
$pbr$::upb_MiniTable_FindFieldByNumber(
- <Self as $pbr$::AssociatedMiniTable>::MINI_TABLE,
+ <Self as $pbr$::AssociatedMiniTable>::mini_table(),
$field_number$
)
};
diff --git a/src/google/protobuf/compiler/rust/generator.cc b/src/google/protobuf/compiler/rust/generator.cc
index 0f44c88..af6cf69 100644
--- a/src/google/protobuf/compiler/rust/generator.cc
+++ b/src/google/protobuf/compiler/rust/generator.cc
@@ -177,15 +177,6 @@
{"Phantom", "::__std::marker::PhantomData"},
});
- // On upb we need to enable this feature to be able to have const pointers to
- // upb_MiniTables while using the upb C minitable codegen. This
- // feature appears that it'll imminently be considered stabilized
- // (https://github.com/rust-lang/rust/issues/128183), and if we emit the
- // MiniTables as const directly in .rs rather than using the upb minitable .h
- // this could be avoided regardless.
- if (ctx.is_upb() && file == &rust_generator_context.primary_file()) {
- ctx.Emit("#![feature(const_refs_to_static)]\n");
- }
ctx.Emit({{"kernel", KernelRsName(ctx.opts().kernel)}}, R"rs(
extern crate protobuf_$kernel$ as __pb;
diff --git a/src/google/protobuf/compiler/rust/message.cc b/src/google/protobuf/compiler/rust/message.cc
index e92c348..9def99c 100644
--- a/src/google/protobuf/compiler/rust/message.cc
+++ b/src/google/protobuf/compiler/rust/message.cc
@@ -80,7 +80,7 @@
// SAFETY: `MINI_TABLE` is the one associated with `self.raw_msg()`.
let encoded = unsafe {
$pbr$::wire::encode(self.raw_msg(),
- <Self as $pbr$::AssociatedMiniTable>::MINI_TABLE)
+ <Self as $pbr$::AssociatedMiniTable>::mini_table())
};
//~ TODO: This discards the info we have about the reason
//~ of the failure, we should try to keep it instead.
@@ -102,12 +102,11 @@
return;
case Kernel::kUpb:
ctx.Emit(
- {
- {"minitable", UpbMinitableName(msg)},
- },
R"rs(
unsafe {
- $pbr$::upb_Message_Clear(self.raw_msg(), $std$::ptr::addr_of!($minitable$))
+ $pbr$::upb_Message_Clear(
+ self.raw_msg(),
+ <Self as $pbr$::AssociatedMiniTable>::mini_table())
}
)rs");
return;
@@ -148,7 +147,7 @@
$pbr$::wire::decode(
data,
msg.raw_msg(),
- <Self as $pbr$::AssociatedMiniTable>::MINI_TABLE,
+ <Self as $pbr$::AssociatedMiniTable>::mini_table(),
msg.arena())
};
match status {
@@ -183,7 +182,7 @@
let string = unsafe {
$pbr$::debug_string(
self.raw_msg(),
- <Self as $pbr$::AssociatedMiniTable>::MINI_TABLE
+ <Self as $pbr$::AssociatedMiniTable>::mini_table()
)
};
write!(f, "{}", string)
@@ -297,7 +296,7 @@
unsafe { $pbr$::upb_Message_DeepCopy(
dst.inner.msg,
self.msg,
- <Self as $pbr$::AssociatedMiniTable>::MINI_TABLE,
+ <Self as $pbr$::AssociatedMiniTable>::mini_table(),
dst.inner.arena.raw(),
) };
dst
@@ -319,16 +318,25 @@
void UpbGeneratedMessageTraitImpls(Context& ctx, const Descriptor& msg) {
if (ctx.opts().kernel == Kernel::kUpb) {
ctx.Emit({{"minitable", UpbMinitableName(msg)}}, R"rs(
- unsafe impl $pbr$::AssociatedMiniTable for $Msg$ {
- const MINI_TABLE: *const $pbr$::upb_MiniTable = unsafe { $std$::ptr::addr_of!($minitable$) };
+ impl $pbr$::AssociatedMiniTable for $Msg$ {
+ #[inline(always)]
+ unsafe fn mini_table() -> *const $pbr$::upb_MiniTable {
+ $std$::ptr::addr_of!($minitable$)
+ }
}
- unsafe impl $pbr$::AssociatedMiniTable for $Msg$View<'_> {
- const MINI_TABLE: *const $pbr$::upb_MiniTable = unsafe { $std$::ptr::addr_of!($minitable$) };
+ impl $pbr$::AssociatedMiniTable for $Msg$View<'_> {
+ #[inline(always)]
+ unsafe fn mini_table() -> *const $pbr$::upb_MiniTable {
+ $std$::ptr::addr_of!($minitable$)
+ }
}
- unsafe impl $pbr$::AssociatedMiniTable for $Msg$Mut<'_> {
- const MINI_TABLE: *const $pbr$::upb_MiniTable = unsafe { $std$::ptr::addr_of!($minitable$) };
+ impl $pbr$::AssociatedMiniTable for $Msg$Mut<'_> {
+ #[inline(always)]
+ unsafe fn mini_table() -> *const $pbr$::upb_MiniTable {
+ $std$::ptr::addr_of!($minitable$)
+ }
}
)rs");
}
@@ -362,7 +370,7 @@
assert!(
$pbr$::upb_Message_MergeFrom(self.raw_msg(),
src.as_view().raw_msg(),
- <Self as $pbr$::AssociatedMiniTable>::MINI_TABLE,
+ <Self as $pbr$::AssociatedMiniTable>::mini_table(),
// Use a nullptr for the ExtensionRegistry.
$std$::ptr::null(),
self.arena().raw())
@@ -568,7 +576,7 @@
// SAFETY:
// - Elements of `src` and `dest` have message minitable `MINI_TABLE`.
unsafe {
- $pbr$::repeated_message_copy_from(src, dest, <Self as $pbr$::AssociatedMiniTable>::MINI_TABLE);
+ $pbr$::repeated_message_copy_from(src, dest, <Self as $pbr$::AssociatedMiniTable>::mini_table());
}
}
