Rollup of 6 pull requests

compiler/rustc_ast_lowering/src/format.rs

@@ -446,7 +446,30 @@ fn expand_format_args<'hir>(
         && argmap.iter().enumerate().all(|(i, (&(j, _), _))| i == j)
         && arguments.iter().skip(1).all(|arg| !may_contain_yield_point(&arg.expr));
 
-    let args = if use_simple_array {
+    let args = if arguments.is_empty() {
+        // Generate:
+        //    &<core::fmt::Argument>::none()
+        //
+        // Note:
+        //     `none()` just returns `[]`. We use `none()` rather than `[]` to limit the lifetime.
+        //
+        //     This makes sure that this still fails to compile, even when the argument is inlined:
+        //
+        //     ```
+        //     let f = format_args!("{}", "a");
+        //     println!("{f}"); // error E0716
+        //     ```
+        //
+        //     Cases where keeping the object around is allowed, such as `format_args!("a")`,
+        //     are handled above by the `allow_const` case.
+        let none_fn = ctx.arena.alloc(ctx.expr_lang_item_type_relative(
+            macsp,
+            hir::LangItem::FormatArgument,
+            sym::none,
+        ));
+        let none = ctx.expr_call(macsp, none_fn, &[]);
+        ctx.expr(macsp, hir::ExprKind::AddrOf(hir::BorrowKind::Ref, hir::Mutability::Not, none))
+    } else if use_simple_array {
         // Generate:
         //     &[
         //         <core::fmt::Argument>::new_display(&arg0),

compiler/rustc_span/src/symbol.rs

@@ -1033,6 +1033,7 @@ symbols! {
         non_exhaustive_omitted_patterns_lint,
         non_lifetime_binders,
         non_modrs_mods,
+        none,
         nontemporal_store,
         noop_method_borrow,
         noop_method_clone,

config.example.toml

@@ -750,6 +750,10 @@ changelog-seen = 2
 # This option will override the same option under [build] section.
 #profiler = build.profiler (bool)
 
+# This option supports enable `rpath` in each target independently, 
+# and will override the same option under [rust] section. It only works on Unix platforms
+#rpath = rust.rpath (bool)
+
 # Force static or dynamic linkage of the standard library for this target. If
 # this target is a host for rustc, this will also affect the linkage of the
 # compiler itself. This is useful for building rustc on targets that normally

library/alloc/src/lib.rs

@@ -113,7 +113,6 @@
 #![feature(const_maybe_uninit_write)]
 #![feature(const_maybe_uninit_zeroed)]
 #![feature(const_pin)]
-#![feature(const_ptr_read)]
 #![feature(const_refs_to_cell)]
 #![feature(const_size_of_val)]
 #![feature(const_waker)]

library/core/src/fmt/rt.rs

@@ -152,6 +152,21 @@ impl<'a> Argument<'a> {
             None
         }
     }
+
+    /// Used by `format_args` when all arguments are gone after inlining,
+    /// when using `&[]` would incorrectly allow for a bigger lifetime.
+    ///
+    /// This fails without format argument inlining, and that shouldn't be different
+    /// when the argument is inlined:
+    ///
+    /// ```compile_fail,E0716
+    /// let f = format_args!("{}", "a");
+    /// println!("{f}");
+    /// ```
+    #[inline(always)]
+    pub fn none() -> [Self; 0] {
+        []
+    }
 }
 
 /// This struct represents the unsafety of constructing an `Arguments`.

library/core/src/intrinsics.rs

@@ -2260,7 +2260,7 @@ extern "rust-intrinsic" {
     /// This intrinsic can *only* be called where the pointer is a local without
     /// projections (`read_via_copy(ptr)`, not `read_via_copy(*ptr)`) so that it
     /// trivially obeys runtime-MIR rules about derefs in operands.
-    #[rustc_const_unstable(feature = "const_ptr_read", issue = "80377")]
+    #[rustc_const_stable(feature = "const_ptr_read", since = "CURRENT_RUSTC_VERSION")]
     #[rustc_nounwind]
     pub fn read_via_copy<T>(ptr: *const T) -> T;
 

library/core/src/lib.rs

@@ -140,7 +140,6 @@
 #![feature(const_pointer_is_aligned)]
 #![feature(const_ptr_as_ref)]
 #![feature(const_ptr_is_null)]
-#![feature(const_ptr_read)]
 #![feature(const_ptr_sub_ptr)]
 #![feature(const_ptr_write)]
 #![feature(const_raw_ptr_comparison)]

library/core/src/ptr/const_ptr.rs

@@ -1195,7 +1195,7 @@ impl<T: ?Sized> *const T {
     ///
     /// [`ptr::read`]: crate::ptr::read()
     #[stable(feature = "pointer_methods", since = "1.26.0")]
-    #[rustc_const_unstable(feature = "const_ptr_read", issue = "80377")]
+    #[rustc_const_stable(feature = "const_ptr_read", since = "CURRENT_RUSTC_VERSION")]
     #[inline]
     #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces
     pub const unsafe fn read(self) -> T
@@ -1236,7 +1236,7 @@ impl<T: ?Sized> *const T {
     ///
     /// [`ptr::read_unaligned`]: crate::ptr::read_unaligned()
     #[stable(feature = "pointer_methods", since = "1.26.0")]
-    #[rustc_const_unstable(feature = "const_ptr_read", issue = "80377")]
+    #[rustc_const_stable(feature = "const_ptr_read", since = "CURRENT_RUSTC_VERSION")]
     #[inline]
     #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces
     pub const unsafe fn read_unaligned(self) -> T

library/core/src/ptr/mod.rs

@@ -1133,7 +1133,8 @@ pub const unsafe fn replace<T>(dst: *mut T, mut src: T) -> T {
 /// [valid]: self#safety
 #[inline]
 #[stable(feature = "rust1", since = "1.0.0")]
-#[rustc_const_unstable(feature = "const_ptr_read", issue = "80377")]
+#[rustc_const_stable(feature = "const_ptr_read", since = "CURRENT_RUSTC_VERSION")]
+#[rustc_allow_const_fn_unstable(const_mut_refs, const_maybe_uninit_as_mut_ptr)]
 #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces
 pub const unsafe fn read<T>(src: *const T) -> T {
     // It would be semantically correct to implement this via `copy_nonoverlapping`
@@ -1249,7 +1250,8 @@ pub const unsafe fn read<T>(src: *const T) -> T {
 /// ```
 #[inline]
 #[stable(feature = "ptr_unaligned", since = "1.17.0")]
-#[rustc_const_unstable(feature = "const_ptr_read", issue = "80377")]
+#[rustc_const_stable(feature = "const_ptr_read", since = "CURRENT_RUSTC_VERSION")]
+#[rustc_allow_const_fn_unstable(const_mut_refs, const_maybe_uninit_as_mut_ptr)]
 #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces
 pub const unsafe fn read_unaligned<T>(src: *const T) -> T {
     let mut tmp = MaybeUninit::<T>::uninit();

library/core/src/ptr/mut_ptr.rs

@@ -1305,7 +1305,7 @@ impl<T: ?Sized> *mut T {
     ///
     /// [`ptr::read`]: crate::ptr::read()
     #[stable(feature = "pointer_methods", since = "1.26.0")]
-    #[rustc_const_unstable(feature = "const_ptr_read", issue = "80377")]
+    #[rustc_const_stable(feature = "const_ptr_read", since = "CURRENT_RUSTC_VERSION")]
     #[inline(always)]
     #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces
     pub const unsafe fn read(self) -> T
@@ -1346,7 +1346,7 @@ impl<T: ?Sized> *mut T {
     ///
     /// [`ptr::read_unaligned`]: crate::ptr::read_unaligned()
     #[stable(feature = "pointer_methods", since = "1.26.0")]
-    #[rustc_const_unstable(feature = "const_ptr_read", issue = "80377")]
+    #[rustc_const_stable(feature = "const_ptr_read", since = "CURRENT_RUSTC_VERSION")]
     #[inline(always)]
     #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces
     pub const unsafe fn read_unaligned(self) -> T

library/core/src/slice/iter/macros.rs

@@ -124,12 +124,10 @@ macro_rules! iterator {
             fn next(&mut self) -> Option<$elem> {
                 // could be implemented with slices, but this avoids bounds checks
 
-                // SAFETY: `assume` calls are safe since a slice's start pointer
-                // must be non-null, and slices over non-ZSTs must also have a
-                // non-null end pointer. The call to `next_unchecked!` is safe
-                // since we check if the iterator is empty first.
+                // SAFETY: `assume` call is safe because slices over non-ZSTs must
+                // have a non-null end pointer. The call to `next_unchecked!` is
+                // safe since we check if the iterator is empty first.
                 unsafe {
-                    assume(!self.ptr.as_ptr().is_null());
                     if !<T>::IS_ZST {
                         assume(!self.end.is_null());
                     }
@@ -339,12 +337,10 @@ macro_rules! iterator {
             fn next_back(&mut self) -> Option<$elem> {
                 // could be implemented with slices, but this avoids bounds checks
 
-                // SAFETY: `assume` calls are safe since a slice's start pointer must be non-null,
-                // and slices over non-ZSTs must also have a non-null end pointer.
-                // The call to `next_back_unchecked!` is safe since we check if the iterator is
-                // empty first.
+                // SAFETY: `assume` call is safe because slices over non-ZSTs must
+                // have a non-null end pointer. The call to `next_back_unchecked!`
+                // is safe since we check if the iterator is empty first.
                 unsafe {
-                    assume(!self.ptr.as_ptr().is_null());
                     if !<T>::IS_ZST {
                         assume(!self.end.is_null());
                     }

library/core/tests/lib.rs

@@ -18,7 +18,6 @@
 #![feature(const_pointer_byte_offsets)]
 #![feature(const_pointer_is_aligned)]
 #![feature(const_ptr_as_ref)]
-#![feature(const_ptr_read)]
 #![feature(const_ptr_write)]
 #![feature(const_trait_impl)]
 #![feature(const_likely)]

src/bootstrap/CHANGELOG.md

@@ -27,6 +27,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
   from the default rust toolchain. [#78513](https://github.com/rust-lang/rust/pull/78513)
 - Add options for enabling overflow checks, one for std (`overflow-checks-std`) and one for everything else (`overflow-checks`). Both default to false.
 - Add llvm option `enable-warnings` to have control on llvm compilation warnings. Default to false.
+- Add `rpath` option in `target` section to support set rpath option for each target independently. [#111242](https://github.com/rust-lang/rust/pull/111242)
 
 
 ## [Version 2] - 2020-09-25

src/bootstrap/builder.rs

@@ -1623,7 +1623,7 @@ impl<'a> Builder<'a> {
         // argument manually via `-C link-args=-Wl,-rpath,...`. Plus isn't it
         // fun to pass a flag to a tool to pass a flag to pass a flag to a tool
         // to change a flag in a binary?
-        if self.config.rust_rpath && util::use_host_linker(target) {
+        if self.config.rpath_enabled(target) && util::use_host_linker(target) {
             let rpath = if target.contains("apple") {
                 // Note that we need to take one extra step on macOS to also pass
                 // `-Wl,-instal_name,@rpath/...` to get things to work right. To

src/bootstrap/config.rs

@@ -467,6 +467,7 @@ pub struct Target {
     pub ndk: Option<PathBuf>,
     pub sanitizers: Option<bool>,
     pub profiler: Option<bool>,
+    pub rpath: Option<bool>,
     pub crt_static: Option<bool>,
     pub musl_root: Option<PathBuf>,
     pub musl_libdir: Option<PathBuf>,
@@ -812,6 +813,7 @@ define_config! {
         android_ndk: Option<String> = "android-ndk",
         sanitizers: Option<bool> = "sanitizers",
         profiler: Option<bool> = "profiler",
+        rpath: Option<bool> = "rpath",
         crt_static: Option<bool> = "crt-static",
         musl_root: Option<String> = "musl-root",
         musl_libdir: Option<String> = "musl-libdir",
@@ -1318,6 +1320,7 @@ impl Config {
                 target.qemu_rootfs = cfg.qemu_rootfs.map(PathBuf::from);
                 target.sanitizers = cfg.sanitizers;
                 target.profiler = cfg.profiler;
+                target.rpath = cfg.rpath;
 
                 config.target_config.insert(TargetSelection::from_user(&triple), target);
             }
@@ -1649,6 +1652,10 @@ impl Config {
         self.target_config.values().any(|t| t.profiler == Some(true)) || self.profiler
     }
 
+    pub fn rpath_enabled(&self, target: TargetSelection) -> bool {
+        self.target_config.get(&target).map(|t| t.rpath).flatten().unwrap_or(self.rust_rpath)
+    }
+
     pub fn llvm_enabled(&self) -> bool {
         self.rust_codegen_backends.contains(&INTERNER.intern_str("llvm"))
     }

src/tools/miri/tests/fail/const-ub-checks.rs

@@ -1,4 +1,3 @@
-#![feature(const_ptr_read)]
 
 const UNALIGNED_READ: () = unsafe {
     let x = &[0u8; 4];

src/tools/tidy/src/ui_tests.rs

@@ -9,7 +9,7 @@ use std::path::{Path, PathBuf};
 
 const ENTRY_LIMIT: usize = 900;
 // FIXME: The following limits should be reduced eventually.
-const ISSUES_ENTRY_LIMIT: usize = 1953;
+const ISSUES_ENTRY_LIMIT: usize = 1920;
 const ROOT_ENTRY_LIMIT: usize = 895;
 
 fn check_entries(tests_path: &Path, bad: &mut bool) {

tests/codegen/slice-iter-nonnull.rs

@@ -0,0 +1,42 @@
+// no-system-llvm
+// compile-flags: -O
+// ignore-debug (these add extra checks that make it hard to verify)
+#![crate_type = "lib"]
+
+// The slice iterator used to `assume` that the `start` pointer was non-null.
+// That ought to be unneeded, though, since the type is `NonNull`, so this test
+// confirms that the appropriate metadata is included to denote that.
+
+// CHECK-LABEL: @slice_iter_next(
+#[no_mangle]
+pub fn slice_iter_next<'a>(it: &mut std::slice::Iter<'a, u32>) -> Option<&'a u32> {
+    // CHECK: %[[ENDP:.+]] = getelementptr{{.+}}ptr %it,{{.+}} 1
+    // CHECK: %[[END:.+]] = load ptr, ptr %[[ENDP]]
+    // CHECK-SAME: !nonnull
+    // CHECK-SAME: !noundef
+    // CHECK: %[[START:.+]] = load ptr, ptr %it,
+    // CHECK-SAME: !nonnull
+    // CHECK-SAME: !noundef
+    // CHECK: icmp eq ptr %[[START]], %[[END]]
+
+    // CHECK: store ptr{{.+}}, ptr %it,
+
+    it.next()
+}
+
+// CHECK-LABEL: @slice_iter_next_back(
+#[no_mangle]
+pub fn slice_iter_next_back<'a>(it: &mut std::slice::Iter<'a, u32>) -> Option<&'a u32> {
+    // CHECK: %[[ENDP:.+]] = getelementptr{{.+}}ptr %it,{{.+}} 1
+    // CHECK: %[[END:.+]] = load ptr, ptr %[[ENDP]]
+    // CHECK-SAME: !nonnull
+    // CHECK-SAME: !noundef
+    // CHECK: %[[START:.+]] = load ptr, ptr %it,
+    // CHECK-SAME: !nonnull
+    // CHECK-SAME: !noundef
+    // CHECK: icmp eq ptr %[[START]], %[[END]]
+
+    // CHECK: store ptr{{.+}}, ptr %[[ENDP]],
+
+    it.next_back()
+}

tests/codegen/vec-shrink-panik.rs

@@ -25,7 +25,7 @@ pub fn issue71861(vec: Vec<u32>) -> Box<[u32]> {
 
     // Call to panic_cannot_unwind in case of double-panic is expected
     // on LLVM 16 and older, but other panics are not.
-    // CHECK: filter
+    // old-CHECK: filter
     // old-NEXT: ; call core::panicking::panic_cannot_unwind
     // old-NEXT: panic_cannot_unwind
 
@@ -40,7 +40,7 @@ pub fn issue75636<'a>(iter: &[&'a str]) -> Box<[&'a str]> {
 
     // Call to panic_cannot_unwind in case of double-panic is expected,
     // on LLVM 16 and older, but other panics are not.
-    // CHECK: filter
+    // old-CHECK: filter
     // old-NEXT: ; call core::panicking::panic_cannot_unwind
     // old-NEXT: panic_cannot_unwind
 

tests/ui/const-generics/issues/issue-105821.rs

@@ -1,7 +1,7 @@
 // check-pass
 
 #![allow(incomplete_features)]
-#![feature(adt_const_params, const_ptr_read, generic_const_exprs)]
+#![feature(adt_const_params, generic_const_exprs)]
 #![allow(dead_code)]
 
 const fn catone<const M: usize>(_a: &[u8; M]) -> [u8; M + 1]

tests/ui/const-ptr/out_of_bounds_read.rs

@@ -1,7 +1,5 @@
 // error-pattern: evaluation of constant value failed
 
-#![feature(const_ptr_read)]
-
 fn main() {
     use std::ptr;
 

tests/ui/const-ptr/out_of_bounds_read.stderr

@@ -6,7 +6,7 @@ error[E0080]: evaluation of constant value failed
 note: inside `std::ptr::read::<u32>`
   --> $SRC_DIR/core/src/ptr/mod.rs:LL:COL
 note: inside `_READ`
-  --> $DIR/out_of_bounds_read.rs:12:33
+  --> $DIR/out_of_bounds_read.rs:10:33
    |
 LL |     const _READ: u32 = unsafe { ptr::read(PAST_END_PTR) };
    |                                 ^^^^^^^^^^^^^^^^^^^^^^^
@@ -21,7 +21,7 @@ note: inside `std::ptr::read::<u32>`
 note: inside `ptr::const_ptr::<impl *const u32>::read`
   --> $SRC_DIR/core/src/ptr/const_ptr.rs:LL:COL
 note: inside `_CONST_READ`
-  --> $DIR/out_of_bounds_read.rs:13:39
+  --> $DIR/out_of_bounds_read.rs:11:39
    |
 LL |     const _CONST_READ: u32 = unsafe { PAST_END_PTR.read() };
    |                                       ^^^^^^^^^^^^^^^^^^^
@@ -36,7 +36,7 @@ note: inside `std::ptr::read::<u32>`
 note: inside `ptr::mut_ptr::<impl *mut u32>::read`
   --> $SRC_DIR/core/src/ptr/mut_ptr.rs:LL:COL
 note: inside `_MUT_READ`
-  --> $DIR/out_of_bounds_read.rs:14:37
+  --> $DIR/out_of_bounds_read.rs:12:37
    |
 LL |     const _MUT_READ: u32 = unsafe { (PAST_END_PTR as *mut u32).read() };
    |                                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

tests/ui/consts/const-eval/ub-ref-ptr.rs

@@ -3,7 +3,6 @@
 // normalize-stderr-test "(the raw bytes of the constant) \(size: [0-9]*, align: [0-9]*\)" -> "$1 (size: $$SIZE, align: $$ALIGN)"
 // normalize-stderr-test "([0-9a-f][0-9a-f] |╾─*a(lloc)?[0-9]+(\+[a-z0-9]+)?─*╼ )+ *│.*" -> "HEX_DUMP"
 #![allow(invalid_value)]
-#![feature(const_ptr_read)]
 
 use std::mem;