Merge pull request #4 from rust-lang/master

update from origin 2020-06-18

Author: richkadel

RELEASES.md

@@ -912,7 +912,7 @@ Compatibility Notes
 [`Duration::mul_f32`]: https://doc.rust-lang.org/std/time/struct.Duration.html#method.mul_f32
 [`Duration::mul_f64`]: https://doc.rust-lang.org/std/time/struct.Duration.html#method.mul_f64
 [`any::type_name`]: https://doc.rust-lang.org/std/any/fn.type_name.html
-[forge-platform-support]: https://forge.rust-lang.org/platform-support.html
+[forge-platform-support]: https://forge.rust-lang.org/release/platform-support.html
 [pipeline-internals]: https://internals.rust-lang.org/t/evaluating-pipelined-rustc-compilation/10199
 
 Version 1.37.0 (2019-08-15)

src/bootstrap/compile.rs

@@ -244,6 +244,16 @@ pub fn std_cargo(builder: &Builder<'_>, target: Interned<String>, stage: u32, ca
     if stage >= 1 {
         cargo.rustflag("-Cembed-bitcode=yes");
     }
+
+    // By default, rustc does not include unwind tables unless they are required
+    // for a particular target. They are not required by RISC-V targets, but
+    // compiling the standard library with them means that users can get
+    // backtraces without having to recompile the standard library themselves.
+    //
+    // This choice was discussed in https://github.com/rust-lang/rust/pull/69890
+    if target.contains("riscv") {
+        cargo.rustflag("-Cforce-unwind-tables=yes");
+    }
 }
 
 #[derive(Debug, Copy, Clone, PartialEq, Eq, Hash)]

src/bootstrap/flags.rs

@@ -149,7 +149,12 @@ To learn more about a subcommand, run `./x.py <subcommand> -h`",
             "N",
         );
         opts.optopt("", "src", "path to the root of the rust checkout", "DIR");
-        opts.optopt("j", "jobs", "number of jobs to run in parallel", "JOBS");
+        let j_msg = format!(
+            "number of jobs to run in parallel; \
+             defaults to {} (this host's logical CPU count)",
+            num_cpus::get()
+        );
+        opts.optopt("j", "jobs", &j_msg, "JOBS");
         opts.optflag("h", "help", "print this help message");
         opts.optopt(
             "",

src/bootstrap/test.rs

@@ -554,7 +554,10 @@ impl Step for Clippy {
 
         builder.add_rustc_lib_path(compiler, &mut cargo);
 
-        builder.run(&mut cargo.into());
+        // FIXME: Disable clippy tests for now, they're failing on master
+        // (generally this would mean a toolstate failure but we don't have
+        // toolstate for clippy anymore).
+        // builder.run(&mut cargo.into());
     }
 }
 

src/bootstrap/toolstate.rs

@@ -272,6 +272,18 @@ impl Builder<'_> {
     /// `rust.save-toolstates` in `config.toml`. If unspecified, nothing will be
     /// done. The file is updated immediately after this function completes.
     pub fn save_toolstate(&self, tool: &str, state: ToolState) {
+        // If we're in a dry run setting we don't want to save toolstates as
+        // that means if we e.g. panic down the line it'll look like we tested
+        // everything (but we actually haven't).
+        if self.config.dry_run {
+            return;
+        }
+        // Toolstate isn't tracked for clippy, but since most tools do, we avoid
+        // checking in all the places we could save toolstate and just do so
+        // here.
+        if tool == "clippy-driver" {
+            return;
+        }
         if let Some(ref path) = self.config.save_toolstates {
             if let Some(parent) = path.parent() {
                 // Ensure the parent directory always exists

src/ci/docker/x86_64-gnu-tools/checktools.sh

@@ -14,11 +14,13 @@ python3 "$X_PY" test --no-fail-fast \
     src/doc/rust-by-example \
     src/doc/embedded-book \
     src/doc/edition-guide \
-    src/tools/clippy \
     src/tools/rls \
     src/tools/rustfmt \
     src/tools/miri \
 
 set -e
 
+# debugging: print out the saved toolstates
+cat /tmp/toolstate/toolstates.json
 python3 "$X_PY" test check-tools
+python3 "$X_PY" test src/tools/clippy

src/libcore/mem/mod.rs

@@ -129,7 +129,7 @@ pub use crate::intrinsics::transmute;
 /// erring on the side of (double-)dropping.
 ///
 /// Also, `ManuallyDrop` prevents us from having to "touch" `v` after transferring the
-/// ownership to `s` - the final step of interacting with `v` to dispoe of it without
+/// ownership to `s` — the final step of interacting with `v` to dispose of it without
 /// running its destructor is entirely avoided.
 ///
 /// [drop]: fn.drop.html

src/libcore/panic.rs

@@ -39,8 +39,7 @@ pub struct PanicInfo<'a> {
 impl<'a> PanicInfo<'a> {
     #[unstable(
         feature = "panic_internals",
-        reason = "internal details of the implementation of the `panic!` \
-                         and related macros",
+        reason = "internal details of the implementation of the `panic!` and related macros",
         issue = "none"
     )]
     #[doc(hidden)]
@@ -55,8 +54,7 @@ impl<'a> PanicInfo<'a> {
 
     #[unstable(
         feature = "panic_internals",
-        reason = "internal details of the implementation of the `panic!` \
-                         and related macros",
+        reason = "internal details of the implementation of the `panic!` and related macros",
         issue = "none"
     )]
     #[doc(hidden)]
@@ -244,8 +242,7 @@ impl<'a> Location<'a> {
 impl<'a> Location<'a> {
     #![unstable(
         feature = "panic_internals",
-        reason = "internal details of the implementation of the `panic!` \
-                          and related macros",
+        reason = "internal details of the implementation of the `panic!` and related macros",
         issue = "none"
     )]
     #[doc(hidden)]

src/libcore/panicking.rs

@@ -22,8 +22,7 @@
 #![allow(dead_code, missing_docs)]
 #![unstable(
     feature = "core_panic",
-    reason = "internal details of the implementation of the `panic!` \
-              and related macros",
+    reason = "internal details of the implementation of the `panic!` and related macros",
     issue = "none"
 )]
 

src/librustc_arena/lib.rs

@@ -333,13 +333,6 @@ impl Default for DroplessArena {
 }
 
 impl DroplessArena {
-    #[inline]
-    fn align(&self, align: usize) {
-        let final_address = ((self.ptr.get() as usize) + align - 1) & !(align - 1);
-        self.ptr.set(final_address as *mut u8);
-        assert!(self.ptr <= self.end);
-    }
-
     #[inline(never)]
     #[cold]
     fn grow(&self, additional: usize) {
@@ -370,30 +363,50 @@ impl DroplessArena {
         }
     }
 
+    /// Allocates a byte slice with specified size and alignment from the
+    /// current memory chunk. Returns `None` if there is no free space left to
+    /// satisfy the request.
     #[inline]
-    pub fn alloc_raw(&self, bytes: usize, align: usize) -> &mut [u8] {
-        unsafe {
-            assert!(bytes != 0);
-
-            self.align(align);
+    fn alloc_raw_without_grow(&self, bytes: usize, align: usize) -> Option<*mut u8> {
+        let ptr = self.ptr.get() as usize;
+        let end = self.end.get() as usize;
+        // The allocation request fits into the current chunk iff:
+        //
+        // let aligned = align_to(ptr, align);
+        // ptr <= aligned && aligned + bytes <= end
+        //
+        // Except that we work with fixed width integers and need to be careful
+        // about potential overflow in the calcuation. If the overflow does
+        // happen, then we definitely don't have enough free and need to grow
+        // the arena.
+        let aligned = ptr.checked_add(align - 1)? & !(align - 1);
+        let new_ptr = aligned.checked_add(bytes)?;
+        if new_ptr <= end {
+            self.ptr.set(new_ptr as *mut u8);
+            Some(aligned as *mut u8)
+        } else {
+            None
+        }
+    }
 
-            let future_end = intrinsics::arith_offset(self.ptr.get(), bytes as isize);
-            if (future_end as *mut u8) > self.end.get() {
-                self.grow(bytes);
+    #[inline]
+    pub fn alloc_raw(&self, bytes: usize, align: usize) -> *mut u8 {
+        assert!(bytes != 0);
+        loop {
+            if let Some(a) = self.alloc_raw_without_grow(bytes, align) {
+                break a;
             }
-
-            let ptr = self.ptr.get();
-            // Set the pointer past ourselves
-            self.ptr.set(intrinsics::arith_offset(self.ptr.get(), bytes as isize) as *mut u8);
-            slice::from_raw_parts_mut(ptr, bytes)
+            // No free space left. Allocate a new chunk to satisfy the request.
+            // On failure the grow will panic or abort.
+            self.grow(bytes);
         }
     }
 
     #[inline]
     pub fn alloc<T>(&self, object: T) -> &mut T {
         assert!(!mem::needs_drop::<T>());
 
-        let mem = self.alloc_raw(mem::size_of::<T>(), mem::align_of::<T>()) as *mut _ as *mut T;
+        let mem = self.alloc_raw(mem::size_of::<T>(), mem::align_of::<T>()) as *mut T;
 
         unsafe {
             // Write into uninitialized memory.
@@ -418,13 +431,11 @@ impl DroplessArena {
         assert!(mem::size_of::<T>() != 0);
         assert!(!slice.is_empty());
 
-        let mem = self.alloc_raw(slice.len() * mem::size_of::<T>(), mem::align_of::<T>()) as *mut _
-            as *mut T;
+        let mem = self.alloc_raw(slice.len() * mem::size_of::<T>(), mem::align_of::<T>()) as *mut T;
 
         unsafe {
-            let arena_slice = slice::from_raw_parts_mut(mem, slice.len());
-            arena_slice.copy_from_slice(slice);
-            arena_slice
+            mem.copy_from_nonoverlapping(slice.as_ptr(), slice.len());
+            slice::from_raw_parts_mut(mem, slice.len())
         }
     }
 
@@ -467,7 +478,7 @@ impl DroplessArena {
                     return &mut [];
                 }
                 let size = len.checked_mul(mem::size_of::<T>()).unwrap();
-                let mem = self.alloc_raw(size, mem::align_of::<T>()) as *mut _ as *mut T;
+                let mem = self.alloc_raw(size, mem::align_of::<T>()) as *mut T;
                 unsafe { self.write_from_iter(iter, len, mem) }
             }
             (_, _) => {
@@ -482,7 +493,7 @@ impl DroplessArena {
                         let len = vec.len();
                         let start_ptr = self
                             .alloc_raw(len * mem::size_of::<T>(), mem::align_of::<T>())
-                            as *mut _ as *mut T;
+                            as *mut T;
                         vec.as_ptr().copy_to_nonoverlapping(start_ptr, len);
                         vec.set_len(0);
                         slice::from_raw_parts_mut(start_ptr, len)
@@ -526,8 +537,7 @@ pub struct DropArena {
 impl DropArena {
     #[inline]
     pub unsafe fn alloc<T>(&self, object: T) -> &mut T {
-        let mem =
-            self.arena.alloc_raw(mem::size_of::<T>(), mem::align_of::<T>()) as *mut _ as *mut T;
+        let mem = self.arena.alloc_raw(mem::size_of::<T>(), mem::align_of::<T>()) as *mut T;
         // Write into uninitialized memory.
         ptr::write(mem, object);
         let result = &mut *mem;
@@ -550,7 +560,7 @@ impl DropArena {
         let start_ptr = self
             .arena
             .alloc_raw(len.checked_mul(mem::size_of::<T>()).unwrap(), mem::align_of::<T>())
-            as *mut _ as *mut T;
+            as *mut T;
 
         let mut destructors = self.destructors.borrow_mut();
         // Reserve space for the destructors so we can't panic while adding them

src/librustc_codegen_ssa/back/linker.rs

@@ -280,7 +280,7 @@ impl<'a> Linker for GccLinker<'a> {
     fn set_output_kind(&mut self, output_kind: LinkOutputKind, out_filename: &Path) {
         match output_kind {
             LinkOutputKind::DynamicNoPicExe => {
-                if !self.is_ld {
+                if !self.is_ld && self.sess.target.target.options.linker_is_gnu {
                     self.cmd.arg("-no-pie");
                 }
             }
@@ -291,7 +291,7 @@ impl<'a> Linker for GccLinker<'a> {
             LinkOutputKind::StaticNoPicExe => {
                 // `-static` works for both gcc wrapper and ld.
                 self.cmd.arg("-static");
-                if !self.is_ld {
+                if !self.is_ld && self.sess.target.target.options.linker_is_gnu {
                     self.cmd.arg("-no-pie");
                 }
             }

src/librustc_infer/traits/mod.rs

@@ -59,7 +59,7 @@ pub type TraitObligation<'tcx> = Obligation<'tcx, ty::PolyTraitPredicate<'tcx>>;
 
 // `PredicateObligation` is used a lot. Make sure it doesn't unintentionally get bigger.
 #[cfg(target_arch = "x86_64")]
-static_assert_size!(PredicateObligation<'_>, 88);
+static_assert_size!(PredicateObligation<'_>, 48);
 
 pub type Obligations<'tcx, O> = Vec<Obligation<'tcx, O>>;
 pub type PredicateObligations<'tcx> = Vec<PredicateObligation<'tcx>>;

src/librustc_infer/traits/util.rs

@@ -142,10 +142,12 @@ fn predicate_obligation<'tcx>(
     predicate: ty::Predicate<'tcx>,
     span: Option<Span>,
 ) -> PredicateObligation<'tcx> {
-    let mut cause = ObligationCause::dummy();
-    if let Some(span) = span {
-        cause.span = span;
-    }
+    let cause = if let Some(span) = span {
+        ObligationCause::dummy_with_span(span)
+    } else {
+        ObligationCause::dummy()
+    };
+
     Obligation { cause, param_env: ty::ParamEnv::empty(), recursion_depth: 0, predicate }
 }
 

src/librustc_middle/macros.rs

@@ -1,16 +1,20 @@
 #[macro_export]
 macro_rules! bug {
-    () => ( bug!("impossible case reached") );
-    ($($message:tt)*) => ({
-        $crate::util::bug::bug_fmt(file!(), line!(), format_args!($($message)*))
-    })
+    () => ( $crate::bug!("impossible case reached") );
+    ($msg:expr) => ({ $crate::util::bug::bug_fmt(::std::format_args!($msg)) });
+    ($msg:expr,) => ({ $crate::bug!($msg) });
+    ($fmt:expr, $($arg:tt)+) => ({
+        $crate::util::bug::bug_fmt(::std::format_args!($fmt, $($arg)+))
+    });
 }
 
 #[macro_export]
 macro_rules! span_bug {
-    ($span:expr, $($message:tt)*) => ({
-        $crate::util::bug::span_bug_fmt(file!(), line!(), $span, format_args!($($message)*))
-    })
+    ($span:expr, $msg:expr) => ({ $crate::util::bug::span_bug_fmt($span, ::std::format_args!($msg)) });
+    ($span:expr, $msg:expr,) => ({ $crate::span_bug!($span, $msg) });
+    ($span:expr, $fmt:expr, $($arg:tt)+) => ({
+        $crate::util::bug::span_bug_fmt($span, ::std::format_args!($fmt, $($arg)+))
+    });
 }
 
 ///////////////////////////////////////////////////////////////////////////