Auto merge of rust-lang#117333 - workingjubilee:rollup-2cjwkc3, r=workingjubilee

Rollup of 8 pull requests

Successful merges:

 - rust-lang#115773 (tvOS simulator support on Apple Silicon for rustc)
 - rust-lang#117162 (Remove `cfg_match` from the prelude)
 - rust-lang#117170 (Add support for i586-unknown-netbsd as target.)
 - rust-lang#117259 (Declare rustc_target's dependency on object/macho)
 - rust-lang#117311 (-Zunpretty help: add missing possible values)
 - rust-lang#117316 (Mark constructor of `BinaryHeap` as const fn)
 - rust-lang#117319 (explain why we don't inline when target features differ)
 - rust-lang#117325 (Small ty::print cleanups)

r? `@ghost`
`@rustbot` modify labels: rollup

Author: bors

compiler/rustc_codegen_ssa/src/back/link.rs

@@ -2880,6 +2880,7 @@ fn add_apple_sdk(cmd: &mut dyn Linker, sess: &Session, flavor: LinkerFlavor) {
     }
 
     let sdk_name = match (arch.as_ref(), os.as_ref()) {
+        ("aarch64", "tvos") if llvm_target.ends_with("-simulator") => "appletvsimulator",
         ("aarch64", "tvos") => "appletvos",
         ("x86_64", "tvos") => "appletvsimulator",
         ("arm", "ios") => "iphoneos",

compiler/rustc_llvm/build.rs

@@ -258,6 +258,12 @@ fn main() {
     {
         println!("cargo:rustc-link-lib=z");
     } else if target.contains("netbsd") {
+        // On NetBSD/i386, gcc and g++ is built for i486 (to maximize backward compat)
+        // However, LLVM insists on using 64-bit atomics.
+        // This gives rise to a need to link rust itself with -latomic for these targets
+        if target.starts_with("i586") || target.starts_with("i686") {
+            println!("cargo:rustc-link-lib=atomic");
+        }
         println!("cargo:rustc-link-lib=z");
         println!("cargo:rustc-link-lib=execinfo");
     }

compiler/rustc_middle/src/ty/print/mod.rs

@@ -12,8 +12,6 @@ pub use self::pretty::*;
 
 pub type PrintError = std::fmt::Error;
 
-// FIXME(eddyb) false positive, the lifetime parameters are used with `P:  Printer<...>`.
-#[allow(unused_lifetimes)]
 pub trait Print<'tcx, P> {
     fn print(&self, cx: &mut P) -> Result<(), PrintError>;
 }

compiler/rustc_middle/src/ty/print/pretty.rs

@@ -53,7 +53,6 @@ macro_rules! p {
 }
 macro_rules! define_scoped_cx {
     ($cx:ident) => {
-        #[allow(unused_macros)]
         macro_rules! scoped_cx {
             () => {
                 $cx
@@ -408,8 +407,6 @@ pub trait PrettyPrinter<'tcx>: Printer<'tcx> + fmt::Write {
         def_id: DefId,
         callers: &mut Vec<DefId>,
     ) -> Result<bool, PrintError> {
-        define_scoped_cx!(self);
-
         debug!("try_print_visible_def_path: def_id={:?}", def_id);
 
         // If `def_id` is a direct or injected extern crate, return the
@@ -1868,8 +1865,6 @@ impl<'tcx> Printer<'tcx> for FmtPrinter<'_, 'tcx> {
         def_id: DefId,
         args: &'tcx [GenericArg<'tcx>],
     ) -> Result<(), PrintError> {
-        define_scoped_cx!(self);
-
         if args.is_empty() {
             match self.try_print_trimmed_def_path(def_id)? {
                 true => return Ok(()),
@@ -2401,8 +2396,6 @@ impl<'tcx> FmtPrinter<'_, 'tcx> {
             let _ = write!(cx, "{cont}");
         };
 
-        define_scoped_cx!(self);
-
         let possible_names = ('a'..='z').rev().map(|s| Symbol::intern(&format!("'{s}")));
 
         let mut available_names = possible_names
@@ -2630,46 +2623,6 @@ where
     }
 }
 
-macro_rules! forward_display_to_print {
-    ($($ty:ty),+) => {
-        // Some of the $ty arguments may not actually use 'tcx
-        $(#[allow(unused_lifetimes)] impl<'tcx> fmt::Display for $ty {
-            fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-                ty::tls::with(|tcx| {
-                    let mut cx = FmtPrinter::new(tcx, Namespace::TypeNS);
-                    tcx.lift(*self)
-                        .expect("could not lift for printing")
-                        .print(&mut cx)?;
-                    f.write_str(&cx.into_buffer())?;
-                    Ok(())
-                })
-            }
-        })+
-    };
-}
-
-macro_rules! define_print_and_forward_display {
-    (($self:ident, $cx:ident): $($ty:ty $print:block)+) => {
-        define_print!(($self, $cx): $($ty $print)*);
-        forward_display_to_print!($($ty),+);
-    };
-}
-
-macro_rules! define_print {
-    (($self:ident, $cx:ident): $($ty:ty $print:block)+) => {
-        $(impl<'tcx, P: PrettyPrinter<'tcx>> Print<'tcx, P> for $ty {
-            fn print(&$self, $cx: &mut P) -> Result<(), PrintError> {
-                #[allow(unused_mut)]
-                let mut $cx = $cx;
-                define_scoped_cx!($cx);
-                let _: () = $print;
-                #[allow(unreachable_code)]
-                Ok(())
-            }
-        })+
-    };
-}
-
 /// Wrapper type for `ty::TraitRef` which opts-in to pretty printing only
 /// the trait path. That is, it will print `Trait<U>` instead of
 /// `<T as Trait<U>>`.
@@ -2744,6 +2697,43 @@ pub struct PrintClosureAsImpl<'tcx> {
     pub closure: ty::ClosureArgs<'tcx>,
 }
 
+macro_rules! forward_display_to_print {
+    ($($ty:ty),+) => {
+        // Some of the $ty arguments may not actually use 'tcx
+        $(#[allow(unused_lifetimes)] impl<'tcx> fmt::Display for $ty {
+            fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+                ty::tls::with(|tcx| {
+                    let mut cx = FmtPrinter::new(tcx, Namespace::TypeNS);
+                    tcx.lift(*self)
+                        .expect("could not lift for printing")
+                        .print(&mut cx)?;
+                    f.write_str(&cx.into_buffer())?;
+                    Ok(())
+                })
+            }
+        })+
+    };
+}
+
+macro_rules! define_print {
+    (($self:ident, $cx:ident): $($ty:ty $print:block)+) => {
+        $(impl<'tcx, P: PrettyPrinter<'tcx>> Print<'tcx, P> for $ty {
+            fn print(&$self, $cx: &mut P) -> Result<(), PrintError> {
+                define_scoped_cx!($cx);
+                let _: () = $print;
+                Ok(())
+            }
+        })+
+    };
+}
+
+macro_rules! define_print_and_forward_display {
+    (($self:ident, $cx:ident): $($ty:ty $print:block)+) => {
+        define_print!(($self, $cx): $($ty $print)*);
+        forward_display_to_print!($($ty),+);
+    };
+}
+
 forward_display_to_print! {
     ty::Region<'tcx>,
     Ty<'tcx>,

compiler/rustc_mir_transform/src/inline.rs

@@ -439,6 +439,11 @@ impl<'tcx> Inliner<'tcx> {
         }
 
         if callee_attrs.target_features != self.codegen_fn_attrs.target_features {
+            // In general it is not correct to inline a callee with target features that are a
+            // subset of the caller. This is because the callee might contain calls, and the ABI of
+            // those calls depends on the target features of the surrounding function. By moving a
+            // `Call` terminator from one MIR body to another with more target features, we might
+            // change the ABI of that call!
             return Err("incompatible target features");
         }
 

compiler/rustc_session/src/options.rs

@@ -1899,6 +1899,7 @@ written to standard error output)"),
         `hir` (the HIR), `hir,identified`,
         `hir,typed` (HIR with types for each node),
         `hir-tree` (dump the raw HIR),
+        `thir-tree`, `thir-flat`,
         `mir` (the MIR), or `mir-cfg` (graphviz formatted MIR)"),
     unsound_mir_opts: bool = (false, parse_bool, [TRACKED],
         "enable unsound and buggy MIR optimizations (default: no)"),

compiler/rustc_target/Cargo.toml

@@ -19,4 +19,4 @@ rustc_index = { path = "../rustc_index" }
 [dependencies.object]
 version = "0.32.0"
 default-features = false
-features = ["elf"]
+features = ["elf", "macho"]

compiler/rustc_target/src/spec/aarch64_apple_tvos_sim.rs

@@ -0,0 +1,31 @@
+use super::apple_base::{opts, tvos_sim_llvm_target, Arch};
+use crate::spec::{FramePointer, Target, TargetOptions};
+
+pub fn target() -> Target {
+    let arch = Arch::Arm64_sim;
+    Target {
+        llvm_target: tvos_sim_llvm_target(arch).into(),
+        pointer_width: 64,
+        data_layout: "e-m:o-i64:64-i128:128-n32:64-S128".into(),
+        arch: arch.target_arch(),
+        options: TargetOptions {
+            features: "+neon,+fp-armv8,+apple-a7".into(),
+            max_atomic_width: Some(128),
+            forces_embed_bitcode: true,
+            frame_pointer: FramePointer::NonLeaf,
+            // Taken from (and slightly modified) the aarch64-apple-ios-sim spec which says:
+            // Taken from a clang build on Xcode 11.4.1.
+            // These arguments are not actually invoked - they just have
+            // to look right to pass App Store validation.
+            bitcode_llvm_cmdline: "-triple\0\
+                arm64-apple-tvos15.0-simulator\0\
+                -emit-obj\0\
+                -disable-llvm-passes\0\
+                -target-abi\0\
+                darwinpcs\0\
+                -Os\0"
+                .into(),
+            ..opts("tvos", arch)
+        },
+    }
+}

compiler/rustc_target/src/spec/i586_unknown_netbsd.rs

@@ -0,0 +1,18 @@
+use crate::spec::{StackProbeType, Target, TargetOptions};
+
+pub fn target() -> Target {
+    let mut base = super::netbsd_base::opts();
+    base.cpu = "pentium".into();
+    base.max_atomic_width = Some(64);
+    base.stack_probes = StackProbeType::Call;
+
+    Target {
+        llvm_target: "i586-unknown-netbsdelf".into(),
+        pointer_width: 32,
+        data_layout: "e-m:e-p:32:32-p270:32:32-p271:32:32-p272:64:64-\
+            f64:32:64-f80:32-n8:16:32-S128"
+            .into(),
+        arch: "x86".into(),
+        options: TargetOptions { mcount: "__mcount".into(), ..base },
+    }
+}

compiler/rustc_target/src/spec/mod.rs

@@ -1564,6 +1564,7 @@ supported_targets! {
     ("aarch64_be-unknown-netbsd", aarch64_be_unknown_netbsd),
     ("armv6-unknown-netbsd-eabihf", armv6_unknown_netbsd_eabihf),
     ("armv7-unknown-netbsd-eabihf", armv7_unknown_netbsd_eabihf),
+    ("i586-unknown-netbsd", i586_unknown_netbsd),
     ("i686-unknown-netbsd", i686_unknown_netbsd),
     ("powerpc-unknown-netbsd", powerpc_unknown_netbsd),
     ("riscv64gc-unknown-netbsd", riscv64gc_unknown_netbsd),
@@ -1603,6 +1604,7 @@ supported_targets! {
     ("aarch64-apple-ios-macabi", aarch64_apple_ios_macabi),
     ("aarch64-apple-ios-sim", aarch64_apple_ios_sim),
     ("aarch64-apple-tvos", aarch64_apple_tvos),
+    ("aarch64-apple-tvos-sim", aarch64_apple_tvos_sim),
     ("x86_64-apple-tvos", x86_64_apple_tvos),
 
     ("armv7k-apple-watchos", armv7k_apple_watchos),