Rollup of 5 pull requests

compiler/rustc_lint/src/nonstandard_style.rs

@@ -10,6 +10,7 @@ use rustc_hir::def::{DefKind, Res};
 use rustc_hir::intravisit::FnKind;
 use rustc_hir::{GenericParamKind, PatKind};
 use rustc_middle::ty;
+use rustc_session::config::CrateType;
 use rustc_span::def_id::LocalDefId;
 use rustc_span::symbol::{sym, Ident};
 use rustc_span::{BytePos, Span};
@@ -331,6 +332,10 @@ impl<'tcx> LateLintPass<'tcx> for NonSnakeCase {
             return;
         }
 
+        if cx.tcx.crate_types().iter().all(|&crate_type| crate_type == CrateType::Executable) {
+            return;
+        }
+
         let crate_ident = if let Some(name) = &cx.tcx.sess.opts.crate_name {
             Some(Ident::from_str(name))
         } else {

compiler/rustc_resolve/src/late.rs

@@ -4150,34 +4150,36 @@ impl<'a: 'ast, 'b, 'ast, 'tcx> LateResolutionVisitor<'a, 'b, 'ast, 'tcx> {
             PathResult::Indeterminate => bug!("indeterminate path result in resolve_qpath"),
         };
 
-        if path.len() > 1
-            && let Some(res) = result.full_res()
-            && let Some((&last_segment, prev_segs)) = path.split_last()
-            && prev_segs.iter().all(|seg| !seg.has_generic_args)
-            && res != Res::Err
-            && path[0].ident.name != kw::PathRoot
-            && path[0].ident.name != kw::DollarCrate
-        {
-            let unqualified_result = {
-                match self.resolve_path(&[last_segment], Some(ns), None) {
-                    PathResult::NonModule(path_res) => path_res.expect_full_res(),
-                    PathResult::Module(ModuleOrUniformRoot::Module(module)) => {
-                        module.res().unwrap()
-                    }
-                    _ => return Ok(Some(result)),
-                }
-            };
-            if res == unqualified_result {
-                let lint = lint::builtin::UNUSED_QUALIFICATIONS;
+        if path.iter().all(|seg| !seg.ident.span.from_expansion()) {
+            let end_pos =
+                path.iter().position(|seg| seg.has_generic_args).map_or(path.len(), |pos| pos + 1);
+            let unqualified =
+                path[..end_pos].iter().enumerate().skip(1).rev().find_map(|(i, seg)| {
+                    // Preserve the current namespace for the final path segment, but use the type
+                    // namespace for all preceding segments
+                    //
+                    // e.g. for `std::env::args` check the `ValueNS` for `args` but the `TypeNS` for
+                    // `std` and `env`
+                    //
+                    // If the final path segment is beyond `end_pos` all the segments to check will
+                    // use the type namespace
+                    let ns = if i + 1 == path.len() { ns } else { TypeNS };
+                    let res = self.r.partial_res_map.get(&seg.id?)?.full_res()?;
+                    let binding = self.resolve_ident_in_lexical_scope(seg.ident, ns, None, None)?;
+
+                    (res == binding.res()).then_some(seg)
+                });
+
+            if let Some(unqualified) = unqualified {
                 self.r.lint_buffer.buffer_lint_with_diagnostic(
-                    lint,
+                    lint::builtin::UNUSED_QUALIFICATIONS,
                     finalize.node_id,
                     finalize.path_span,
                     "unnecessary qualification",
                     lint::BuiltinLintDiagnostics::UnusedQualifications {
-                        removal_span: finalize.path_span.until(last_segment.ident.span),
+                        removal_span: finalize.path_span.until(unqualified.ident.span),
                     },
-                )
+                );
             }
         }
 

library/core/src/ptr/mod.rs

@@ -574,6 +574,8 @@ pub const fn null_mut<T: ?Sized + Thin>() -> *mut T {
 
 /// Creates a pointer with the given address and no provenance.
 ///
+/// This is equivalent to `ptr::null().with_addr(addr)`.
+///
 /// Without provenance, this pointer is not associated with any actual allocation. Such a
 /// no-provenance pointer may be used for zero-sized memory accesses (if suitably aligned), but
 /// non-zero-sized memory accesses with a no-provenance pointer are UB. No-provenance pointers are
@@ -616,6 +618,8 @@ pub const fn dangling<T>() -> *const T {
 
 /// Creates a pointer with the given address and no provenance.
 ///
+/// This is equivalent to `ptr::null_mut().with_addr(addr)`.
+///
 /// Without provenance, this pointer is not associated with any actual allocation. Such a
 /// no-provenance pointer may be used for zero-sized memory accesses (if suitably aligned), but
 /// non-zero-sized memory accesses with a no-provenance pointer are UB. No-provenance pointers are