Auto merge of rust-lang#131914 - workingjubilee:rollup-o0p7v51, r=workingjubilee

Rollup of 8 pull requests

Successful merges:

 - rust-lang#127462 (std: uefi: Add basic Env variables)
 - rust-lang#131537 (Fix range misleading field access)
 - rust-lang#131838 (bootstrap: allow setting `--jobs` in config.toml)
 - rust-lang#131871 (x86-32 float return for 'Rust' ABI: treat all float types consistently)
 - rust-lang#131876 (compiler: Use LLVM's Comdat support)
 - rust-lang#131890 (Update `use` keyword docs to describe precise capturing)
 - rust-lang#131899 (Mark unexpected variant res suggestion as having placeholders)
 - rust-lang#131908 (rustdoc: Switch from FxHash to sha256 for static file hashing.)

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

Author: bors

Cargo.lock

@@ -4584,6 +4584,7 @@ dependencies = [
  "rustdoc-json-types",
  "serde",
  "serde_json",
+ "sha2",
  "smallvec",
  "tempfile",
  "threadpool",

compiler/rustc_codegen_llvm/src/coverageinfo/mapgen.rs

@@ -132,7 +132,7 @@ pub(crate) fn finalize(cx: &CodegenCx<'_, '_>) {
             .collect::<Vec<_>>();
         let initializer = cx.const_array(cx.type_ptr(), &name_globals);
 
-        let array = llvm::add_global(cx.llmod, cx.val_ty(initializer), "__llvm_coverage_names");
+        let array = llvm::add_global(cx.llmod, cx.val_ty(initializer), c"__llvm_coverage_names");
         llvm::set_global_constant(array, true);
         llvm::set_linkage(array, llvm::Linkage::InternalLinkage);
         llvm::set_initializer(array, initializer);

compiler/rustc_codegen_llvm/src/coverageinfo/mod.rs

@@ -1,4 +1,5 @@
 use std::cell::RefCell;
+use std::ffi::CString;
 
 use libc::c_uint;
 use rustc_codegen_ssa::traits::{
@@ -12,6 +13,7 @@ use rustc_middle::mir::coverage::CoverageKind;
 use rustc_middle::ty::Instance;
 use rustc_middle::ty::layout::HasTyCtxt;
 use rustc_target::abi::{Align, Size};
+use rustc_target::spec::HasTargetSpec;
 use tracing::{debug, instrument};
 
 use crate::builder::Builder;
@@ -284,10 +286,10 @@ pub(crate) fn save_cov_data_to_mod<'ll, 'tcx>(
     cx: &CodegenCx<'ll, 'tcx>,
     cov_data_val: &'ll llvm::Value,
 ) {
-    let covmap_var_name = llvm::build_string(|s| unsafe {
+    let covmap_var_name = CString::new(llvm::build_byte_buffer(|s| unsafe {
         llvm::LLVMRustCoverageWriteMappingVarNameToString(s);
-    })
-    .expect("Rust Coverage Mapping var name failed UTF-8 conversion");
+    }))
+    .unwrap();
     debug!("covmap var name: {:?}", covmap_var_name);
 
     let covmap_section_name = llvm::build_string(|s| unsafe {
@@ -322,7 +324,8 @@ pub(crate) fn save_func_record_to_mod<'ll, 'tcx>(
     // of descriptions play distinct roles in LLVM IR; therefore, assign them different names (by
     // appending "u" to the end of the function record var name, to prevent `linkonce_odr` merging.
     let func_record_var_name =
-        format!("__covrec_{:X}{}", func_name_hash, if is_used { "u" } else { "" });
+        CString::new(format!("__covrec_{:X}{}", func_name_hash, if is_used { "u" } else { "" }))
+            .unwrap();
     debug!("function record var name: {:?}", func_record_var_name);
     debug!("function record section name: {:?}", covfun_section_name);
 
@@ -334,7 +337,9 @@ pub(crate) fn save_func_record_to_mod<'ll, 'tcx>(
     llvm::set_section(llglobal, covfun_section_name);
     // LLVM's coverage mapping format specifies 8-byte alignment for items in this section.
     llvm::set_alignment(llglobal, Align::EIGHT);
-    llvm::set_comdat(cx.llmod, llglobal, &func_record_var_name);
+    if cx.target_spec().supports_comdat() {
+        llvm::set_comdat(cx.llmod, llglobal, &func_record_var_name);
+    }
     cx.add_used_global(llglobal);
 }
 

compiler/rustc_codegen_llvm/src/llvm/ffi.rs

@@ -646,6 +646,7 @@ unsafe extern "C" {
     pub type Attribute;
     pub type Metadata;
     pub type BasicBlock;
+    pub type Comdat;
 }
 #[repr(C)]
 pub struct Builder<'a>(InvariantOpaque<'a>);
@@ -1490,6 +1491,9 @@ unsafe extern "C" {
     pub fn LLVMSetUnnamedAddress(Global: &Value, UnnamedAddr: UnnamedAddr);
 
     pub fn LLVMIsAConstantInt(value_ref: &Value) -> Option<&ConstantInt>;
+
+    pub fn LLVMGetOrInsertComdat(M: &Module, Name: *const c_char) -> &Comdat;
+    pub fn LLVMSetComdat(V: &Value, C: &Comdat);
 }
 
 #[link(name = "llvm-wrapper", kind = "static")]
@@ -2320,7 +2324,6 @@ unsafe extern "C" {
 
     pub fn LLVMRustPositionBuilderAtStart<'a>(B: &Builder<'a>, BB: &'a BasicBlock);
 
-    pub fn LLVMRustSetComdat<'a>(M: &'a Module, V: &'a Value, Name: *const c_char, NameLen: size_t);
     pub fn LLVMRustSetModulePICLevel(M: &Module);
     pub fn LLVMRustSetModulePIELevel(M: &Module);
     pub fn LLVMRustSetModuleCodeModel(M: &Module, Model: CodeModel);

compiler/rustc_codegen_llvm/src/llvm/mod.rs

@@ -178,10 +178,10 @@ pub fn SetFunctionCallConv(fn_: &Value, cc: CallConv) {
 // function.
 // For more details on COMDAT sections see e.g., https://www.airs.com/blog/archives/52
 pub fn SetUniqueComdat(llmod: &Module, val: &Value) {
-    unsafe {
-        let name = get_value_name(val);
-        LLVMRustSetComdat(llmod, val, name.as_ptr().cast(), name.len());
-    }
+    let name_buf = get_value_name(val).to_vec();
+    let name =
+        CString::from_vec_with_nul(name_buf).or_else(|buf| CString::new(buf.into_bytes())).unwrap();
+    set_comdat(llmod, val, &name);
 }
 
 pub fn SetUnnamedAddress(global: &Value, unnamed: UnnamedAddr) {
@@ -217,8 +217,7 @@ pub fn set_section(llglobal: &Value, section_name: &str) {
     }
 }
 
-pub fn add_global<'a>(llmod: &'a Module, ty: &'a Type, name: &str) -> &'a Value {
-    let name_cstr = CString::new(name).expect("unexpected CString error");
+pub fn add_global<'a>(llmod: &'a Module, ty: &'a Type, name_cstr: &CStr) -> &'a Value {
     unsafe { LLVMAddGlobal(llmod, ty, name_cstr.as_ptr()) }
 }
 
@@ -252,9 +251,14 @@ pub fn set_alignment(llglobal: &Value, align: Align) {
     }
 }
 
-pub fn set_comdat(llmod: &Module, llglobal: &Value, name: &str) {
+/// Get the `name`d comdat from `llmod` and assign it to `llglobal`.
+///
+/// Inserts the comdat into `llmod` if it does not exist.
+/// It is an error to call this if the target does not support comdat.
+pub fn set_comdat(llmod: &Module, llglobal: &Value, name: &CStr) {
     unsafe {
-        LLVMRustSetComdat(llmod, llglobal, name.as_ptr().cast(), name.len());
+        let comdat = LLVMGetOrInsertComdat(llmod, name.as_ptr());
+        LLVMSetComdat(llglobal, comdat);
     }
 }
 

compiler/rustc_hir_typeck/src/lib.rs

@@ -419,7 +419,7 @@ fn report_unexpected_variant_res(
                 }
             }
 
-            err.multipart_suggestion_verbose(descr, suggestion, Applicability::MaybeIncorrect);
+            err.multipart_suggestion_verbose(descr, suggestion, Applicability::HasPlaceholders);
             err
         }
         Res::Def(DefKind::Variant, _) if expr.is_none() => {

compiler/rustc_llvm/llvm-wrapper/RustWrapper.cpp

@@ -1658,16 +1658,6 @@ extern "C" void LLVMRustPositionBuilderAtStart(LLVMBuilderRef B,
   unwrap(B)->SetInsertPoint(unwrap(BB), Point);
 }
 
-extern "C" void LLVMRustSetComdat(LLVMModuleRef M, LLVMValueRef V,
-                                  const char *Name, size_t NameLen) {
-  Triple TargetTriple = Triple(unwrap(M)->getTargetTriple());
-  GlobalObject *GV = unwrap<GlobalObject>(V);
-  if (TargetTriple.supportsCOMDAT()) {
-    StringRef NameRef(Name, NameLen);
-    GV->setComdat(unwrap(M)->getOrInsertComdat(NameRef));
-  }
-}
-
 enum class LLVMRustLinkage {
   ExternalLinkage = 0,
   AvailableExternallyLinkage = 1,

compiler/rustc_resolve/src/late.rs

@@ -4011,6 +4011,7 @@ impl<'a, 'ast, 'ra: 'ast, 'tcx> LateResolutionVisitor<'a, 'ast, 'ra, 'tcx> {
                 let instead = res.is_some();
                 let suggestion = if let Some((start, end)) = this.diag_metadata.in_range
                     && path[0].ident.span.lo() == end.span.lo()
+                    && !matches!(start.kind, ExprKind::Lit(_))
                 {
                     let mut sugg = ".";
                     let mut span = start.span.between(end.span);

compiler/rustc_target/src/spec/mod.rs

@@ -2514,6 +2514,13 @@ fn add_link_args(link_args: &mut LinkArgs, flavor: LinkerFlavor, args: &[&'stati
     add_link_args_iter(link_args, flavor, args.iter().copied().map(Cow::Borrowed))
 }
 
+impl TargetOptions {
+    pub fn supports_comdat(&self) -> bool {
+        // XCOFF and MachO don't support COMDAT.
+        !self.is_like_aix && !self.is_like_osx
+    }
+}
+
 impl TargetOptions {
     fn link_args(flavor: LinkerFlavor, args: &[&'static str]) -> LinkArgs {
         let mut link_args = LinkArgs::new();

compiler/rustc_ty_utils/src/abi.rs

@@ -1,6 +1,5 @@
 use std::iter;
 
-use rustc_abi::Float::*;
 use rustc_abi::Primitive::{Float, Pointer};
 use rustc_abi::{Abi, AddressSpace, PointerKind, Scalar, Size};
 use rustc_hir as hir;
@@ -695,37 +694,31 @@ fn fn_abi_adjust_for_abi<'tcx>(
             }
 
             // Avoid returning floats in x87 registers on x86 as loading and storing from x87
-            // registers will quiet signalling NaNs.
+            // registers will quiet signalling NaNs. Also avoid using SSE registers since they
+            // are not always available (depending on target features).
             if tcx.sess.target.arch == "x86"
                 && arg_idx.is_none()
                 // Intrinsics themselves are not actual "real" functions, so theres no need to
                 // change their ABIs.
                 && abi != SpecAbi::RustIntrinsic
             {
-                match arg.layout.abi {
-                    // Handle similar to the way arguments with an `Abi::Aggregate` abi are handled
-                    // below, by returning arguments up to the size of a pointer (32 bits on x86)
-                    // cast to an appropriately sized integer.
-                    Abi::Scalar(s) if s.primitive() == Float(F32) => {
-                        // Same size as a pointer, return in a register.
-                        arg.cast_to(Reg::i32());
-                        return;
+                let has_float = match arg.layout.abi {
+                    Abi::Scalar(s) => matches!(s.primitive(), Float(_)),
+                    Abi::ScalarPair(s1, s2) => {
+                        matches!(s1.primitive(), Float(_)) || matches!(s2.primitive(), Float(_))
                     }
-                    Abi::Scalar(s) if s.primitive() == Float(F64) => {
-                        // Larger than a pointer, return indirectly.
-                        arg.make_indirect();
-                        return;
-                    }
-                    Abi::ScalarPair(s1, s2)
-                        if matches!(s1.primitive(), Float(F32 | F64))
-                            || matches!(s2.primitive(), Float(F32 | F64)) =>
-                    {
+                    _ => false, // anyway not passed via registers on x86
+                };
+                if has_float {
+                    if arg.layout.size <= Pointer(AddressSpace::DATA).size(cx) {
+                        // Same size or smaller than pointer, return in a register.
+                        arg.cast_to(Reg { kind: RegKind::Integer, size: arg.layout.size });
+                    } else {
                         // Larger than a pointer, return indirectly.
                         arg.make_indirect();
-                        return;
                     }
-                    _ => {}
-                };
+                    return;
+                }
             }
 
             match arg.layout.abi {