Auto merge of #86091 - JohnTitor:rollup-wceot6d, r=JohnTitor

Rollup of 6 pull requests

Successful merges:

 - #84262 (Fix ICE during type layout when there's a `[type error]`)
 - #85973 (Replace a `match` with an `if let`)
 - #85996 (rustbuild: take changes to the standard library into account for `download-rustc`)
 - #86016 (Unify duplicate linker_and_flavor methods in rustc_codegen_{cranelift,ssa}.)
 - #86025 (Remove the install prefix from the rpath set when using -Crpath)
 - #86081 (Use `try_into` instead of asserting manually)

Failed merges:

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

compiler/rustc_codegen_cranelift/src/toolchain.rs

@@ -2,9 +2,8 @@
 
 use std::path::PathBuf;
 
-use rustc_middle::bug;
+use rustc_codegen_ssa::back::link::linker_and_flavor;
 use rustc_session::Session;
-use rustc_target::spec::LinkerFlavor;
 
 /// Tries to infer the path of a binary for the target toolchain from the linker name.
 pub(crate) fn get_toolchain_binary(sess: &Session, tool: &str) -> PathBuf {
@@ -30,90 +29,3 @@ pub(crate) fn get_toolchain_binary(sess: &Session, tool: &str) -> PathBuf {
 
     linker
 }
-
-// Adapted from https://github.com/rust-lang/rust/blob/5db778affee7c6600c8e7a177c48282dab3f6292/src/librustc_codegen_ssa/back/link.rs#L848-L931
-fn linker_and_flavor(sess: &Session) -> (PathBuf, LinkerFlavor) {
-    fn infer_from(
-        sess: &Session,
-        linker: Option<PathBuf>,
-        flavor: Option<LinkerFlavor>,
-    ) -> Option<(PathBuf, LinkerFlavor)> {
-        match (linker, flavor) {
-            (Some(linker), Some(flavor)) => Some((linker, flavor)),
-            // only the linker flavor is known; use the default linker for the selected flavor
-            (None, Some(flavor)) => Some((
-                PathBuf::from(match flavor {
-                    LinkerFlavor::Em => {
-                        if cfg!(windows) {
-                            "emcc.bat"
-                        } else {
-                            "emcc"
-                        }
-                    }
-                    LinkerFlavor::Gcc => {
-                        if cfg!(any(target_os = "solaris", target_os = "illumos")) {
-                            // On historical Solaris systems, "cc" may have
-                            // been Sun Studio, which is not flag-compatible
-                            // with "gcc".  This history casts a long shadow,
-                            // and many modern illumos distributions today
-                            // ship GCC as "gcc" without also making it
-                            // available as "cc".
-                            "gcc"
-                        } else {
-                            "cc"
-                        }
-                    }
-                    LinkerFlavor::Ld => "ld",
-                    LinkerFlavor::Msvc => "link.exe",
-                    LinkerFlavor::Lld(_) => "lld",
-                    LinkerFlavor::PtxLinker => "rust-ptx-linker",
-                    LinkerFlavor::BpfLinker => "bpf-linker",
-                }),
-                flavor,
-            )),
-            (Some(linker), None) => {
-                let stem = linker.file_stem().and_then(|stem| stem.to_str()).unwrap_or_else(|| {
-                    sess.fatal("couldn't extract file stem from specified linker")
-                });
-
-                let flavor = if stem == "emcc" {
-                    LinkerFlavor::Em
-                } else if stem == "gcc"
-                    || stem.ends_with("-gcc")
-                    || stem == "clang"
-                    || stem.ends_with("-clang")
-                {
-                    LinkerFlavor::Gcc
-                } else if stem == "ld" || stem == "ld.lld" || stem.ends_with("-ld") {
-                    LinkerFlavor::Ld
-                } else if stem == "link" || stem == "lld-link" {
-                    LinkerFlavor::Msvc
-                } else if stem == "lld" || stem == "rust-lld" {
-                    LinkerFlavor::Lld(sess.target.lld_flavor)
-                } else {
-                    // fall back to the value in the target spec
-                    sess.target.linker_flavor
-                };
-
-                Some((linker, flavor))
-            }
-            (None, None) => None,
-        }
-    }
-
-    // linker and linker flavor specified via command line have precedence over what the target
-    // specification specifies
-    if let Some(ret) = infer_from(sess, sess.opts.cg.linker.clone(), sess.opts.cg.linker_flavor) {
-        return ret;
-    }
-
-    if let Some(ret) = infer_from(
-        sess,
-        sess.target.linker.clone().map(PathBuf::from),
-        Some(sess.target.linker_flavor),
-    ) {
-        return ret;
-    }
-
-    bug!("Not enough information provided to determine how to invoke the linker");
-}

compiler/rustc_codegen_ssa/src/back/link.rs

@@ -1147,7 +1147,8 @@ pub fn ignored_for_lto(sess: &Session, info: &CrateInfo, cnum: CrateNum) -> bool
         && (info.compiler_builtins == Some(cnum) || info.is_no_builtins.contains(&cnum))
 }
 
-fn linker_and_flavor(sess: &Session) -> (PathBuf, LinkerFlavor) {
+// This functions tries to determine the appropriate linker (and corresponding LinkerFlavor) to use
+pub fn linker_and_flavor(sess: &Session) -> (PathBuf, LinkerFlavor) {
     fn infer_from(
         sess: &Session,
         linker: Option<PathBuf>,
@@ -1714,24 +1715,14 @@ fn add_rpath_args(
 ) {
     // FIXME (#2397): At some point we want to rpath our guesses as to
     // where extern libraries might live, based on the
-    // addl_lib_search_paths
+    // add_lib_search_paths
     if sess.opts.cg.rpath {
-        let target_triple = sess.opts.target_triple.triple();
-        let mut get_install_prefix_lib_path = || {
-            let install_prefix = option_env!("CFG_PREFIX").expect("CFG_PREFIX");
-            let tlib = rustc_target::target_rustlib_path(&sess.sysroot, target_triple).join("lib");
-            let mut path = PathBuf::from(install_prefix);
-            path.push(&tlib);
-
-            path
-        };
         let mut rpath_config = RPathConfig {
             used_crates: &codegen_results.crate_info.used_crates_dynamic,
             out_filename: out_filename.to_path_buf(),
             has_rpath: sess.target.has_rpath,
             is_like_osx: sess.target.is_like_osx,
             linker_is_gnu: sess.target.linker_is_gnu,
-            get_install_prefix_lib_path: &mut get_install_prefix_lib_path,
         };
         cmd.args(&rpath::get_rpath_flags(&mut rpath_config));
     }

compiler/rustc_codegen_ssa/src/back/rpath.rs

@@ -13,7 +13,6 @@ pub struct RPathConfig<'a> {
     pub is_like_osx: bool,
     pub has_rpath: bool,
     pub linker_is_gnu: bool,
-    pub get_install_prefix_lib_path: &'a mut dyn FnMut() -> PathBuf,
 }
 
 pub fn get_rpath_flags(config: &mut RPathConfig<'_>) -> Vec<String> {
@@ -63,24 +62,13 @@ fn get_rpaths(config: &mut RPathConfig<'_>, libs: &[PathBuf]) -> Vec<String> {
     // Use relative paths to the libraries. Binaries can be moved
     // as long as they maintain the relative relationship to the
     // crates they depend on.
-    let rel_rpaths = get_rpaths_relative_to_output(config, libs);
+    let rpaths = get_rpaths_relative_to_output(config, libs);
 
-    // And a final backup rpath to the global library location.
-    let fallback_rpaths = vec![get_install_prefix_rpath(config)];
-
-    fn log_rpaths(desc: &str, rpaths: &[String]) {
-        debug!("{} rpaths:", desc);
-        for rpath in rpaths {
-            debug!("    {}", *rpath);
-        }
+    debug!("rpaths:");
+    for rpath in &rpaths {
+        debug!("    {}", rpath);
     }
 
-    log_rpaths("relative", &rel_rpaths);
-    log_rpaths("fallback", &fallback_rpaths);
-
-    let mut rpaths = rel_rpaths;
-    rpaths.extend_from_slice(&fallback_rpaths);
-
     // Remove duplicates
     minimize_rpaths(&rpaths)
 }
@@ -113,13 +101,6 @@ fn path_relative_from(path: &Path, base: &Path) -> Option<PathBuf> {
     diff_paths(path, base)
 }
 
-fn get_install_prefix_rpath(config: &mut RPathConfig<'_>) -> String {
-    let path = (config.get_install_prefix_lib_path)();
-    let path = env::current_dir().unwrap().join(&path);
-    // FIXME (#9639): This needs to handle non-utf8 paths
-    path.to_str().expect("non-utf8 component in rpath").to_owned()
-}
-
 fn minimize_rpaths(rpaths: &[String]) -> Vec<String> {
     let mut set = FxHashSet::default();
     let mut minimized = Vec::new();

compiler/rustc_codegen_ssa/src/back/rpath/tests.rs

@@ -40,15 +40,13 @@ fn test_rpath_relative() {
             is_like_osx: true,
             linker_is_gnu: false,
             out_filename: PathBuf::from("bin/rustc"),
-            get_install_prefix_lib_path: &mut || panic!(),
         };
         let res = get_rpath_relative_to_output(config, Path::new("lib/libstd.so"));
         assert_eq!(res, "@loader_path/../lib");
     } else {
         let config = &mut RPathConfig {
             used_crates: &[],
             out_filename: PathBuf::from("bin/rustc"),
-            get_install_prefix_lib_path: &mut || panic!(),
             has_rpath: true,
             is_like_osx: false,
             linker_is_gnu: true,

compiler/rustc_middle/src/ty/layout.rs

@@ -367,7 +367,14 @@ impl<'tcx> LayoutCx<'tcx, TyCtxt<'tcx>> {
         for &i in &inverse_memory_index {
             let field = fields[i as usize];
             if !sized {
-                bug!("univariant: field #{} of `{}` comes after unsized field", offsets.len(), ty);
+                self.tcx.sess.delay_span_bug(
+                    DUMMY_SP,
+                    &format!(
+                        "univariant: field #{} of `{}` comes after unsized field",
+                        offsets.len(),
+                        ty
+                    ),
+                );
             }
 
             if field.is_unsized() {

compiler/rustc_mir/src/transform/remove_zsts.rs

@@ -16,32 +16,29 @@ impl<'tcx> MirPass<'tcx> for RemoveZsts {
         let (basic_blocks, local_decls) = body.basic_blocks_and_local_decls_mut();
         for block in basic_blocks.iter_mut() {
             for statement in block.statements.iter_mut() {
-                match statement.kind {
-                    StatementKind::Assign(box (place, _)) => {
-                        let place_ty = place.ty(local_decls, tcx).ty;
-                        if !maybe_zst(place_ty) {
-                            continue;
-                        }
-                        let layout = match tcx.layout_of(param_env.and(place_ty)) {
-                            Ok(layout) => layout,
-                            Err(_) => continue,
-                        };
-                        if !layout.is_zst() {
-                            continue;
-                        }
-                        if involves_a_union(place, local_decls, tcx) {
-                            continue;
-                        }
-                        if tcx.consider_optimizing(|| {
-                            format!(
-                                "RemoveZsts - Place: {:?} SourceInfo: {:?}",
-                                place, statement.source_info
-                            )
-                        }) {
-                            statement.make_nop();
-                        }
+                if let StatementKind::Assign(box (place, _)) = statement.kind {
+                    let place_ty = place.ty(local_decls, tcx).ty;
+                    if !maybe_zst(place_ty) {
+                        continue;
+                    }
+                    let layout = match tcx.layout_of(param_env.and(place_ty)) {
+                        Ok(layout) => layout,
+                        Err(_) => continue,
+                    };
+                    if !layout.is_zst() {
+                        continue;
+                    }
+                    if involves_a_union(place, local_decls, tcx) {
+                        continue;
+                    }
+                    if tcx.consider_optimizing(|| {
+                        format!(
+                            "RemoveZsts - Place: {:?} SourceInfo: {:?}",
+                            place, statement.source_info
+                        )
+                    }) {
+                        statement.make_nop();
                     }
-                    _ => {}
                 }
             }
         }

compiler/rustc_target/src/abi/mod.rs

@@ -753,11 +753,7 @@ impl FieldsShape {
         match *self {
             FieldsShape::Primitive => 0,
             FieldsShape::Union(count) => count.get(),
-            FieldsShape::Array { count, .. } => {
-                let usize_count = count as usize;
-                assert_eq!(usize_count as u64, count);
-                usize_count
-            }
+            FieldsShape::Array { count, .. } => count.try_into().unwrap(),
             FieldsShape::Arbitrary { ref offsets, .. } => offsets.len(),
         }
     }
@@ -791,11 +787,7 @@ impl FieldsShape {
                 unreachable!("FieldsShape::memory_index: `Primitive`s have no fields")
             }
             FieldsShape::Union(_) | FieldsShape::Array { .. } => i,
-            FieldsShape::Arbitrary { ref memory_index, .. } => {
-                let r = memory_index[i];
-                assert_eq!(r as usize as u32, r);
-                r as usize
-            }
+            FieldsShape::Arbitrary { ref memory_index, .. } => memory_index[i].try_into().unwrap(),
         }
     }
 

src/bootstrap/bootstrap.py

@@ -648,18 +648,20 @@ def maybe_download_ci_toolchain(self):
         rev_parse = ["git", "rev-parse", "--show-toplevel"]
         top_level = subprocess.check_output(rev_parse, universal_newlines=True).strip()
         compiler = "{}/compiler/".format(top_level)
+        library = "{}/library/".format(top_level)
 
         # Look for a version to compare to based on the current commit.
         # Only commits merged by bors will have CI artifacts.
         merge_base = ["git", "log", "--author=bors", "--pretty=%H", "-n1"]
         commit = subprocess.check_output(merge_base, universal_newlines=True).strip()
 
-        # Warn if there were changes to the compiler since the ancestor commit.
-        status = subprocess.call(["git", "diff-index", "--quiet", commit, "--", compiler])
+        # Warn if there were changes to the compiler or standard library since the ancestor commit.
+        status = subprocess.call(["git", "diff-index", "--quiet", commit, "--", compiler, library])
         if status != 0:
             if download_rustc == "if-unchanged":
                 return None
-            print("warning: `download-rustc` is enabled, but there are changes to compiler/")
+            print("warning: `download-rustc` is enabled, but there are changes to \
+                   compiler/ or library/")
 
         if self.verbose:
             print("using downloaded stage1 artifacts from CI (commit {})".format(commit))

src/bootstrap/compile.rs

@@ -636,8 +636,7 @@ pub fn rustc_cargo_env(builder: &Builder<'_>, cargo: &mut Cargo, target: TargetS
     cargo
         .env("CFG_RELEASE", builder.rust_release())
         .env("CFG_RELEASE_CHANNEL", &builder.config.channel)
-        .env("CFG_VERSION", builder.rust_version())
-        .env("CFG_PREFIX", builder.config.prefix.clone().unwrap_or_default());
+        .env("CFG_VERSION", builder.rust_version());
 
     let libdir_relative = builder.config.libdir_relative().unwrap_or_else(|| Path::new("lib"));
     cargo.env("CFG_LIBDIR_RELATIVE", libdir_relative);

src/test/ui/layout/issue-84108.rs

@@ -0,0 +1,14 @@
+// See issue #84108 -- this is a test to ensure we do not ICE
+// on this invalid code.
+
+#![crate_type = "lib"]
+
+static FOO: (dyn AsRef<OsStr>, u8) = ("hello", 42);
+//~^ ERROR cannot find type `OsStr` in this scope
+
+const BAR: (&Path, [u8], usize) = ("hello", [], 42);
+//~^ ERROR cannot find type `Path` in this scope
+//~| ERROR the size for values of type `[u8]` cannot be known at compilation time
+
+static BAZ: ([u8], usize) = ([], 0);
+//~^ ERROR the size for values of type `[u8]` cannot be known at compilation time

src/test/ui/layout/issue-84108.stderr

@@ -0,0 +1,44 @@
+error[E0412]: cannot find type `OsStr` in this scope
+  --> $DIR/issue-84108.rs:6:24
+   |
+LL | static FOO: (dyn AsRef<OsStr>, u8) = ("hello", 42);
+   |                        ^^^^^ not found in this scope
+   |
+help: consider importing this struct
+   |
+LL | use std::ffi::OsStr;
+   |
+
+error[E0412]: cannot find type `Path` in this scope
+  --> $DIR/issue-84108.rs:9:14
+   |
+LL | const BAR: (&Path, [u8], usize) = ("hello", [], 42);
+   |              ^^^^ not found in this scope
+   |
+help: consider importing this struct
+   |
+LL | use std::path::Path;
+   |
+
+error[E0277]: the size for values of type `[u8]` cannot be known at compilation time
+  --> $DIR/issue-84108.rs:9:12
+   |
+LL | const BAR: (&Path, [u8], usize) = ("hello", [], 42);
+   |            ^^^^^^^^^^^^^^^^^^^^ doesn't have a size known at compile-time
+   |
+   = help: the trait `Sized` is not implemented for `[u8]`
+   = note: only the last element of a tuple may have a dynamically sized type
+
+error[E0277]: the size for values of type `[u8]` cannot be known at compilation time
+  --> $DIR/issue-84108.rs:13:13
+   |
+LL | static BAZ: ([u8], usize) = ([], 0);
+   |             ^^^^^^^^^^^^^ doesn't have a size known at compile-time
+   |
+   = help: the trait `Sized` is not implemented for `[u8]`
+   = note: only the last element of a tuple may have a dynamically sized type
+
+error: aborting due to 4 previous errors
+
+Some errors have detailed explanations: E0277, E0412.
+For more information about an error, try `rustc --explain E0277`.