diff options
| -rw-r--r-- | compiler/rustc_middle/src/mir/mono.rs | 6 | ||||
| -rw-r--r-- | compiler/rustc_middle/src/ty/context.rs | 14 | ||||
| -rw-r--r-- | compiler/rustc_monomorphize/src/collector.rs | 9 | ||||
| -rw-r--r-- | compiler/rustc_monomorphize/src/partitioning.rs | 15 | ||||
| -rw-r--r-- | tests/ui/entry-point/auxiliary/main_functions.rs | 3 | ||||
| -rw-r--r-- | tests/ui/entry-point/imported_main_local_codegen.rs | 11 |
6 files changed, 44 insertions, 14 deletions
diff --git a/compiler/rustc_middle/src/mir/mono.rs b/compiler/rustc_middle/src/mir/mono.rs index 47ba850d50d..c2927361d05 100644 --- a/compiler/rustc_middle/src/mir/mono.rs +++ b/compiler/rustc_middle/src/mir/mono.rs @@ -143,10 +143,8 @@ impl<'tcx> MonoItem<'tcx> { }; // Similarly, the executable entrypoint must be instantiated exactly once. - if let Some((entry_def_id, _)) = tcx.entry_fn(()) { - if instance.def_id() == entry_def_id { - return InstantiationMode::GloballyShared { may_conflict: false }; - } + if tcx.is_entrypoint(instance.def_id()) { + return InstantiationMode::GloballyShared { may_conflict: false }; } // If the function is #[naked] or contains any other attribute that requires exactly-once diff --git a/compiler/rustc_middle/src/ty/context.rs b/compiler/rustc_middle/src/ty/context.rs index 915b062417f..26da2abe126 100644 --- a/compiler/rustc_middle/src/ty/context.rs +++ b/compiler/rustc_middle/src/ty/context.rs @@ -3402,6 +3402,20 @@ impl<'tcx> TyCtxt<'tcx> { pub fn do_not_recommend_impl(self, def_id: DefId) -> bool { self.get_diagnostic_attr(def_id, sym::do_not_recommend).is_some() } + + /// Whether this def is one of the special bin crate entrypoint functions that must have a + /// monomorphization and also not be internalized in the bin crate. + pub fn is_entrypoint(self, def_id: DefId) -> bool { + if self.is_lang_item(def_id, LangItem::Start) { + return true; + } + if let Some((entry_def_id, _)) = self.entry_fn(()) + && entry_def_id == def_id + { + return true; + } + false + } } /// Parameter attributes that can only be determined by examining the body of a function instead diff --git a/compiler/rustc_monomorphize/src/collector.rs b/compiler/rustc_monomorphize/src/collector.rs index 91c8e64ce9a..5071f9f8922 100644 --- a/compiler/rustc_monomorphize/src/collector.rs +++ b/compiler/rustc_monomorphize/src/collector.rs @@ -1582,6 +1582,15 @@ impl<'v> RootCollector<'_, 'v> { return; }; + let main_instance = Instance::mono(self.tcx, main_def_id); + if self.tcx.should_codegen_locally(main_instance) { + self.output.push(create_fn_mono_item( + self.tcx, + main_instance, + self.tcx.def_span(main_def_id), + )); + } + let Some(start_def_id) = self.tcx.lang_items().start_fn() else { self.tcx.dcx().emit_fatal(errors::StartNotFound); }; diff --git a/compiler/rustc_monomorphize/src/partitioning.rs b/compiler/rustc_monomorphize/src/partitioning.rs index 69851511fb1..ca8228de57e 100644 --- a/compiler/rustc_monomorphize/src/partitioning.rs +++ b/compiler/rustc_monomorphize/src/partitioning.rs @@ -223,11 +223,7 @@ where // So even if its mode is LocalCopy, we need to treat it like a root. match mono_item.instantiation_mode(cx.tcx) { InstantiationMode::GloballyShared { .. } => {} - InstantiationMode::LocalCopy => { - if !cx.tcx.is_lang_item(mono_item.def_id(), LangItem::Start) { - continue; - } - } + InstantiationMode::LocalCopy => continue, } let characteristic_def_id = characteristic_def_id_of_mono_item(cx.tcx, mono_item); @@ -821,10 +817,9 @@ fn mono_item_visibility<'tcx>( | InstanceKind::FnPtrAddrShim(..) => return Visibility::Hidden, }; - // The `start_fn` lang item is actually a monomorphized instance of a - // function in the standard library, used for the `main` function. We don't - // want to export it so we tag it with `Hidden` visibility but this symbol - // is only referenced from the actual `main` symbol which we unfortunately + // Both the `start_fn` lang item and `main` itself should not be exported, + // so we give them with `Hidden` visibility but these symbols are + // only referenced from the actual `main` symbol which we unfortunately // don't know anything about during partitioning/collection. As a result we // forcibly keep this symbol out of the `internalization_candidates` set. // @@ -834,7 +829,7 @@ fn mono_item_visibility<'tcx>( // from the `main` symbol we'll generate later. // // This may be fixable with a new `InstanceKind` perhaps? Unsure! - if tcx.is_lang_item(def_id, LangItem::Start) { + if tcx.is_entrypoint(def_id) { *can_be_internalized = false; return Visibility::Hidden; } diff --git a/tests/ui/entry-point/auxiliary/main_functions.rs b/tests/ui/entry-point/auxiliary/main_functions.rs index cc7992a42c1..ab4a09b6331 100644 --- a/tests/ui/entry-point/auxiliary/main_functions.rs +++ b/tests/ui/entry-point/auxiliary/main_functions.rs @@ -1 +1,4 @@ pub fn boilerplate() {} + +#[inline] +pub fn local_codegen() {} diff --git a/tests/ui/entry-point/imported_main_local_codegen.rs b/tests/ui/entry-point/imported_main_local_codegen.rs new file mode 100644 index 00000000000..1e46c109373 --- /dev/null +++ b/tests/ui/entry-point/imported_main_local_codegen.rs @@ -0,0 +1,11 @@ +//@ run-pass +//@ aux-build:main_functions.rs +//@ compile-flags: -Ccodegen-units=1024 + +// This is a regression test for https://github.com/rust-lang/rust/issues/144052. +// Entrypoint functions call each other in ways that CGU partitioning doesn't know about. So there +// is a special check to not internalize any of them. But internalizing them can be okay if there +// are few enough CGUs, so we use a lot of CGUs in this test to hit the bad case. + +extern crate main_functions; +pub use main_functions::local_codegen as main; |