Auto merge of #61819 - Centril:rollup-k2gprnz, r=Centril

Rollup of 5 pull requests

Successful merges:

 - #61704 (Pass LLVM linker flags to librustc_llvm build)
 - #61792 (Add ui test for issue 51301)
 - #61803 (typeck: small refactoring, add 'fn write_resolution')
 - #61805 (typeck: Fix ICE for blocks in repeat expr count.)
 - #61818 (Issue #60709 test)

Failed merges:

r? @ghost

src/bootstrap/compile.rs

@@ -775,6 +775,10 @@ pub fn build_codegen_backend(builder: &Builder<'_>,
                     cargo.env("CFG_LLVM_ROOT", s);
                 }
             }
+            // Some LLVM linker flags (-L and -l) may be needed to link librustc_llvm.
+            if let Some(ref s) = builder.config.llvm_ldflags {
+                cargo.env("LLVM_LINKER_FLAGS", s);
+            }
             // Building with a static libstdc++ is only supported on linux right now,
             // not for MSVC or macOS
             if builder.config.llvm_static_stdcpp &&

src/librustc_llvm/build.rs

@@ -234,6 +234,21 @@ fn main() {
         }
     }
 
+    // Some LLVM linker flags (-L and -l) may be needed even when linking
+    // librustc_llvm, for example when using static libc++, we may need to
+    // manually specify the library search path and -ldl -lpthread as link
+    // dependencies.
+    let llvm_linker_flags = env::var_os("LLVM_LINKER_FLAGS");
+    if let Some(s) = llvm_linker_flags {
+        for lib in s.into_string().unwrap().split_whitespace() {
+            if lib.starts_with("-l") {
+                println!("cargo:rustc-link-lib={}", &lib[2..]);
+            } else if lib.starts_with("-L") {
+                println!("cargo:rustc-link-search=native={}", &lib[2..]);
+            }
+        }
+    }
+
     let llvm_static_stdcpp = env::var_os("LLVM_STATIC_STDCPP");
     let llvm_use_libcxx = env::var_os("LLVM_USE_LIBCXX");
 

src/librustc_typeck/astconv.rs

@@ -2157,6 +2157,14 @@ impl<'o, 'gcx: 'tcx, 'tcx> dyn AstConv<'gcx, 'tcx> + 'o {
 
     /// Returns the `DefId` of the constant parameter that the provided expression is a path to.
     pub fn const_param_def_id(&self, expr: &hir::Expr) -> Option<DefId> {
+        // Unwrap a block, so that e.g. `{ P }` is recognised as a parameter. Const arguments
+        // currently have to be wrapped in curly brackets, so it's necessary to special-case.
+        let expr = match &expr.node {
+            ExprKind::Block(block, _) if block.stmts.is_empty() && block.expr.is_some() =>
+                block.expr.as_ref().unwrap(),
+            _ => expr,
+        };
+
         match &expr.node {
             ExprKind::Path(hir::QPath::Resolved(_, path)) => match path.res {
                 Res::Def(DefKind::ConstParam, did) => Some(did),
@@ -2184,18 +2192,7 @@ impl<'o, 'gcx: 'tcx, 'tcx> dyn AstConv<'gcx, 'tcx> + 'o {
             ty,
         };
 
-        let mut expr = &tcx.hir().body(ast_const.body).value;
-
-        // Unwrap a block, so that e.g. `{ P }` is recognised as a parameter. Const arguments
-        // currently have to be wrapped in curly brackets, so it's necessary to special-case.
-        if let ExprKind::Block(block, _) = &expr.node {
-            if block.stmts.is_empty() {
-                if let Some(trailing) = &block.expr {
-                    expr = &trailing;
-                }
-            }
-        }
-
+        let expr = &tcx.hir().body(ast_const.body).value;
         if let Some(def_id) = self.const_param_def_id(expr) {
             // Find the name and index of the const parameter by indexing the generics of the
             // parent item and construct a `ParamConst`.

src/librustc_typeck/check/mod.rs

@@ -2208,15 +2208,15 @@ impl<'a, 'gcx, 'tcx> FnCtxt<'a, 'gcx, 'tcx> {
         self.tables.borrow_mut().field_indices_mut().insert(hir_id, index);
     }
 
+    fn write_resolution(&self, hir_id: hir::HirId, r: Result<(DefKind, DefId), ErrorReported>) {
+        self.tables.borrow_mut().type_dependent_defs_mut().insert(hir_id, r);
+    }
+
     pub fn write_method_call(&self,
                              hir_id: hir::HirId,
                              method: MethodCallee<'tcx>) {
         debug!("write_method_call(hir_id={:?}, method={:?})", hir_id, method);
-        self.tables
-            .borrow_mut()
-            .type_dependent_defs_mut()
-            .insert(hir_id, Ok((DefKind::Method, method.def_id)));
-
+        self.write_resolution(hir_id, Ok((DefKind::Method, method.def_id)));
         self.write_substs(hir_id, method.substs);
 
         // When the method is confirmed, the `method.substs` includes
@@ -4724,7 +4724,7 @@ impl<'a, 'gcx, 'tcx> FnCtxt<'a, 'gcx, 'tcx> {
                 let result = result.map(|(_, kind, def_id)| (kind, def_id));
 
                 // Write back the new resolution.
-                self.tables.borrow_mut().type_dependent_defs_mut().insert(hir_id, result);
+                self.write_resolution(hir_id, result);
 
                 (result.map(|(kind, def_id)| Res::Def(kind, def_id)).unwrap_or(Res::Err), ty)
             }
@@ -4777,7 +4777,7 @@ impl<'a, 'gcx, 'tcx> FnCtxt<'a, 'gcx, 'tcx> {
         });
 
         // Write back the new resolution.
-        self.tables.borrow_mut().type_dependent_defs_mut().insert(hir_id, result);
+        self.write_resolution(hir_id, result);
         (
             result.map(|(kind, def_id)| Res::Def(kind, def_id)).unwrap_or(Res::Err),
             Some(ty),

src/test/run-pass/async-await/issue-60709.rs

@@ -0,0 +1,28 @@
+// This used to compile the future down to ud2, due to uninhabited types being
+// handled incorrectly in generators.
+// compile-flags: -Copt-level=z -Cdebuginfo=2 --edition=2018
+
+#![feature(async_await, await_macro)]
+#![allow(unused)]
+
+use std::future::Future;
+use std::task::Poll;
+use std::task::Context;
+use std::pin::Pin;
+use std::rc::Rc;
+
+struct Never();
+impl Future for Never {
+    type Output = ();
+    fn poll(self: Pin<&mut Self>, _cx: &mut Context<'_>) -> Poll<Self::Output> {
+        Poll::Pending
+    }
+}
+
+fn main() {
+    let fut = async {
+        let _rc = Rc::new(()); // Also crashes with Arc
+        await!(Never());
+    };
+    let _bla = fut; // Moving the future is required.
+}

src/test/ui/const-generics/issue-61336-2.rs

@@ -0,0 +1,16 @@
+#![feature(const_generics)]
+//~^ WARN the feature `const_generics` is incomplete and may cause the compiler to crash
+
+fn f<T: Copy, const N: usize>(x: T) -> [T; N] {
+    [x; {N}]
+}
+
+fn g<T, const N: usize>(x: T) -> [T; N] {
+    [x; {N}]
+    //~^ ERROR the trait bound `T: std::marker::Copy` is not satisfied [E0277]
+}
+
+fn main() {
+    let x: [u32; 5] = f::<u32, 5>(3);
+    assert_eq!(x, [3u32; 5]);
+}

src/test/ui/const-generics/issue-61336-2.stderr

@@ -0,0 +1,18 @@
+warning: the feature `const_generics` is incomplete and may cause the compiler to crash
+  --> $DIR/issue-61336-2.rs:1:12
+   |
+LL | #![feature(const_generics)]
+   |            ^^^^^^^^^^^^^^
+
+error[E0277]: the trait bound `T: std::marker::Copy` is not satisfied
+  --> $DIR/issue-61336-2.rs:9:5
+   |
+LL |     [x; {N}]
+   |     ^^^^^^^^ the trait `std::marker::Copy` is not implemented for `T`
+   |
+   = help: consider adding a `where T: std::marker::Copy` bound
+   = note: the `Copy` trait is required because the repeated element will be copied
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0277`.

src/test/ui/issues/issue-51301.rs

@@ -0,0 +1,35 @@
+use std::any::TypeId;
+use std::collections::HashMap;
+use std::hash::Hash;
+
+trait State {
+    type EventType;
+    fn get_type_id_of_state(&self) -> TypeId;
+}
+
+struct StateMachine<EventType: Hash + Eq> {
+    current_state: Box<dyn State<EventType = EventType>>,
+    transition_table:
+        HashMap<TypeId, HashMap<EventType, fn() -> Box<dyn State<EventType = EventType>>>>,
+}
+
+impl<EventType: Hash + Eq> StateMachine<EventType> {
+    fn inner_process_event(&mut self, event: EventType) -> Result<(), i8> {
+        let new_state_creation_function = self
+            .transition_table
+            .iter()
+            .find(|(&event_typeid, _)| event_typeid == self.current_state.get_type_id_of_state())
+            .ok_or(1)?
+            .1
+            .iter()
+            .find(|(&event_type, _)| event == event_type)
+            //~^ ERROR cannot move out of a shared reference
+            .ok_or(2)?
+            .1;
+
+        self.current_state = new_state_creation_function();
+        Ok(())
+    }
+}
+
+fn main() {}

src/test/ui/issues/issue-51301.stderr

@@ -0,0 +1,12 @@
+error[E0507]: cannot move out of a shared reference
+  --> $DIR/issue-51301.rs:25:20
+   |
+LL |             .find(|(&event_type, _)| event == event_type)
+   |                    ^^----------^^^^
+   |                      |
+   |                      data moved here
+   |                      move occurs because `event_type` has type `EventType`, which does not implement the `Copy` trait
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0507`.