Auto merge of #110598 - matthiaskrgr:rollup-0ybd9i3, r=matthiaskrgr

Rollup of 5 pull requests

Successful merges:

 - #110240 (Add `indent_style = tab` for `Makefile`s to `.editorconfig`)
 - #110545 (Add `GenericArgKind::as_{type,const,region}`)
 - #110574 ( fix out-of-date comment about rpath in bootstrap)
 - #110581 (Style fix for loongarch-linux.md)
 - #110584 (Allow overwriting the sysroot compile flag in compile tests)

Failed merges:

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

12 files changed, 96 insertions, 114 deletions

diff --git a/.editorconfig b/.editorconfig
index 03aab32bfc6..d065fa46469 100644
--- a/.editorconfig
+++ b/.editorconfig
@@ -20,3 +20,6 @@ trim_trailing_whitespace = false
 
 [*.yml]
 indent_size = 2
+
+[Makefile]
+indent_style = tab
diff --git a/compiler/rustc_codegen_llvm/src/debuginfo/metadata.rs b/compiler/rustc_codegen_llvm/src/debuginfo/metadata.rs
index 21a0a60b012..25fe3cb265d 100644
--- a/compiler/rustc_codegen_llvm/src/debuginfo/metadata.rs
+++ b/compiler/rustc_codegen_llvm/src/debuginfo/metadata.rs
@@ -29,7 +29,6 @@ use rustc_hir::def::CtorKind;
 use rustc_hir::def_id::{DefId, LOCAL_CRATE};
 use rustc_middle::bug;
 use rustc_middle::ty::layout::{LayoutOf, TyAndLayout};
-use rustc_middle::ty::subst::GenericArgKind;
 use rustc_middle::ty::{
     self, AdtKind, Instance, ParamEnv, PolyExistentialTraitRef, Ty, TyCtxt, Visibility,
 };
@@ -1182,12 +1181,12 @@ fn build_generic_type_param_di_nodes<'ll, 'tcx>(
             let names = get_parameter_names(cx, generics);
             let template_params: SmallVec<_> = iter::zip(substs, names)
                 .filter_map(|(kind, name)| {
-                    if let GenericArgKind::Type(ty) = kind.unpack() {
+                    kind.as_type().map(|ty| {
                         let actual_type =
                             cx.tcx.normalize_erasing_regions(ParamEnv::reveal_all(), ty);
                         let actual_type_di_node = type_di_node(cx, actual_type);
                         let name = name.as_str();
-                        Some(unsafe {
+                        unsafe {
                             llvm::LLVMRustDIBuilderCreateTemplateTypeParameter(
                                 DIB(cx),
                                 None,
@@ -1195,10 +1194,8 @@ fn build_generic_type_param_di_nodes<'ll, 'tcx>(
                                 name.len(),
                                 actual_type_di_node,
                             )
-                        })
-                    } else {
-                        None
-                    }
+                        }
+                    })
                 })
                 .collect();
 
diff --git a/compiler/rustc_codegen_llvm/src/debuginfo/mod.rs b/compiler/rustc_codegen_llvm/src/debuginfo/mod.rs
index 56844c7951f..dfc226db57b 100644
--- a/compiler/rustc_codegen_llvm/src/debuginfo/mod.rs
+++ b/compiler/rustc_codegen_llvm/src/debuginfo/mod.rs
@@ -27,7 +27,7 @@ use rustc_hir::def_id::{DefId, DefIdMap};
 use rustc_index::vec::IndexVec;
 use rustc_middle::mir;
 use rustc_middle::ty::layout::LayoutOf;
-use rustc_middle::ty::subst::{GenericArgKind, SubstsRef};
+use rustc_middle::ty::subst::SubstsRef;
 use rustc_middle::ty::{self, Instance, ParamEnv, Ty, TypeVisitableExt};
 use rustc_session::config::{self, DebugInfo};
 use rustc_session::Session;
@@ -461,12 +461,12 @@ impl<'ll, 'tcx> DebugInfoMethods<'tcx> for CodegenCx<'ll, 'tcx> {
                 let names = get_parameter_names(cx, generics);
                 iter::zip(substs, names)
                     .filter_map(|(kind, name)| {
-                        if let GenericArgKind::Type(ty) = kind.unpack() {
+                        kind.as_type().map(|ty| {
                             let actual_type =
                                 cx.tcx.normalize_erasing_regions(ParamEnv::reveal_all(), ty);
                             let actual_type_metadata = type_di_node(cx, actual_type);
                             let name = name.as_str();
-                            Some(unsafe {
+                            unsafe {
                                 Some(llvm::LLVMRustDIBuilderCreateTemplateTypeParameter(
                                     DIB(cx),
                                     None,
@@ -474,10 +474,8 @@ impl<'ll, 'tcx> DebugInfoMethods<'tcx> for CodegenCx<'ll, 'tcx> {
                                     name.len(),
                                     actual_type_metadata,
                                 ))
-                            })
-                        } else {
-                            None
-                        }
+                            }
+                        })
                     })
                     .collect()
             } else {
diff --git a/compiler/rustc_codegen_ssa/src/meth.rs b/compiler/rustc_codegen_ssa/src/meth.rs
index 2421acab471..81b49afb883 100644
--- a/compiler/rustc_codegen_ssa/src/meth.rs
+++ b/compiler/rustc_codegen_ssa/src/meth.rs
@@ -67,10 +67,10 @@ impl<'a, 'tcx> VirtualIndex {
 /// ref of the type.
 fn expect_dyn_trait_in_self(ty: Ty<'_>) -> ty::PolyExistentialTraitRef<'_> {
     for arg in ty.peel_refs().walk() {
-        if let GenericArgKind::Type(ty) = arg.unpack() {
-            if let ty::Dynamic(data, _, _) = ty.kind() {
-                return data.principal().expect("expected principal trait object");
-            }
+        if let GenericArgKind::Type(ty) = arg.unpack()
+            && let ty::Dynamic(data, _, _) = ty.kind()
+        {
+            return data.principal().expect("expected principal trait object");
         }
     }
 
diff --git a/compiler/rustc_hir_typeck/src/fn_ctxt/mod.rs b/compiler/rustc_hir_typeck/src/fn_ctxt/mod.rs
index c6fd0b61035..3ba679df3ed 100644
--- a/compiler/rustc_hir_typeck/src/fn_ctxt/mod.rs
+++ b/compiler/rustc_hir_typeck/src/fn_ctxt/mod.rs
@@ -17,7 +17,6 @@ use rustc_infer::infer;
 use rustc_infer::infer::error_reporting::TypeErrCtxt;
 use rustc_infer::infer::type_variable::{TypeVariableOrigin, TypeVariableOriginKind};
 use rustc_middle::infer::unify_key::{ConstVariableOrigin, ConstVariableOriginKind};
-use rustc_middle::ty::subst::GenericArgKind;
 use rustc_middle::ty::{self, Const, Ty, TyCtxt, TypeVisitableExt};
 use rustc_session::Session;
 use rustc_span::symbol::Ident;
@@ -250,16 +249,12 @@ impl<'a, 'tcx> AstConv<'tcx> for FnCtxt<'a, 'tcx> {
     }
 
     fn ty_infer(&self, param: Option<&ty::GenericParamDef>, span: Span) -> Ty<'tcx> {
-        if let Some(param) = param {
-            if let GenericArgKind::Type(ty) = self.var_for_def(span, param).unpack() {
-                return ty;
-            }
-            unreachable!()
-        } else {
-            self.next_ty_var(TypeVariableOrigin {
+        match param {
+            Some(param) => self.var_for_def(span, param).as_type().unwrap(),
+            None => self.next_ty_var(TypeVariableOrigin {
                 kind: TypeVariableOriginKind::TypeInference,
                 span,
-            })
+            }),
         }
     }
 
@@ -269,16 +264,12 @@ impl<'a, 'tcx> AstConv<'tcx> for FnCtxt<'a, 'tcx> {
         param: Option<&ty::GenericParamDef>,
         span: Span,
     ) -> Const<'tcx> {
-        if let Some(param) = param {
-            if let GenericArgKind::Const(ct) = self.var_for_def(span, param).unpack() {
-                return ct;
-            }
-            unreachable!()
-        } else {
-            self.next_const_var(
+        match param {
+            Some(param) => self.var_for_def(span, param).as_const().unwrap(),
+            None => self.next_const_var(
                 ty,
                 ConstVariableOrigin { kind: ConstVariableOriginKind::ConstInference, span },
-            )
+            ),
         }
     }
 
diff --git a/compiler/rustc_lint/src/builtin.rs b/compiler/rustc_lint/src/builtin.rs
index 55bef6d3b3d..aeb791901bd 100644
--- a/compiler/rustc_lint/src/builtin.rs
+++ b/compiler/rustc_lint/src/builtin.rs
@@ -166,10 +166,8 @@ declare_lint_pass!(BoxPointers => [BOX_POINTERS]);
 impl BoxPointers {
     fn check_heap_type(&self, cx: &LateContext<'_>, span: Span, ty: Ty<'_>) {
         for leaf in ty.walk() {
-            if let GenericArgKind::Type(leaf_ty) = leaf.unpack() {
-                if leaf_ty.is_box() {
-                    cx.emit_spanned_lint(BOX_POINTERS, span, BuiltinBoxPointers { ty });
-                }
+            if let GenericArgKind::Type(leaf_ty) = leaf.unpack() && leaf_ty.is_box() {
+                cx.emit_spanned_lint(BOX_POINTERS, span, BuiltinBoxPointers { ty });
             }
         }
     }
diff --git a/compiler/rustc_middle/src/ty/subst.rs b/compiler/rustc_middle/src/ty/subst.rs
index da3cd27f388..3e1b0706f66 100644
--- a/compiler/rustc_middle/src/ty/subst.rs
+++ b/compiler/rustc_middle/src/ty/subst.rs
@@ -167,30 +167,45 @@ impl<'tcx> GenericArg<'tcx> {
         }
     }
 
-    /// Unpack the `GenericArg` as a region when it is known certainly to be a region.
-    pub fn expect_region(self) -> ty::Region<'tcx> {
+    #[inline]
+    pub fn as_type(self) -> Option<Ty<'tcx>> {
+        match self.unpack() {
+            GenericArgKind::Type(ty) => Some(ty),
+            _ => None,
+        }
+    }
+
+    #[inline]
+    pub fn as_region(self) -> Option<ty::Region<'tcx>> {
         match self.unpack() {
-            GenericArgKind::Lifetime(lt) => lt,
-            _ => bug!("expected a region, but found another kind"),
+            GenericArgKind::Lifetime(re) => Some(re),
+            _ => None,
         }
     }
 
+    #[inline]
+    pub fn as_const(self) -> Option<ty::Const<'tcx>> {
+        match self.unpack() {
+            GenericArgKind::Const(ct) => Some(ct),
+            _ => None,
+        }
+    }
+
+    /// Unpack the `GenericArg` as a region when it is known certainly to be a region.
+    pub fn expect_region(self) -> ty::Region<'tcx> {
+        self.as_region().unwrap_or_else(|| bug!("expected a region, but found another kind"))
+    }
+
     /// Unpack the `GenericArg` as a type when it is known certainly to be a type.
     /// This is true in cases where `Substs` is used in places where the kinds are known
     /// to be limited (e.g. in tuples, where the only parameters are type parameters).
     pub fn expect_ty(self) -> Ty<'tcx> {
-        match self.unpack() {
-            GenericArgKind::Type(ty) => ty,
-            _ => bug!("expected a type, but found another kind"),
-        }
+        self.as_type().unwrap_or_else(|| bug!("expected a type, but found another kind"))
     }
 
     /// Unpack the `GenericArg` as a const when it is known certainly to be a const.
     pub fn expect_const(self) -> ty::Const<'tcx> {
-        match self.unpack() {
-            GenericArgKind::Const(c) => c,
-            _ => bug!("expected a const, but found another kind"),
-        }
+        self.as_const().unwrap_or_else(|| bug!("expected a const, but found another kind"))
     }
 
     pub fn is_non_region_infer(self) -> bool {
@@ -369,22 +384,17 @@ impl<'tcx> InternalSubsts<'tcx> {
 
     #[inline]
     pub fn types(&'tcx self) -> impl DoubleEndedIterator<Item = Ty<'tcx>> + 'tcx {
-        self.iter()
-            .filter_map(|k| if let GenericArgKind::Type(ty) = k.unpack() { Some(ty) } else { None })
+        self.iter().filter_map(|k| k.as_type())
     }
 
     #[inline]
     pub fn regions(&'tcx self) -> impl DoubleEndedIterator<Item = ty::Region<'tcx>> + 'tcx {
-        self.iter().filter_map(|k| {
-            if let GenericArgKind::Lifetime(lt) = k.unpack() { Some(lt) } else { None }
-        })
+        self.iter().filter_map(|k| k.as_region())
     }
 
     #[inline]
     pub fn consts(&'tcx self) -> impl DoubleEndedIterator<Item = ty::Const<'tcx>> + 'tcx {
-        self.iter().filter_map(|k| {
-            if let GenericArgKind::Const(ct) = k.unpack() { Some(ct) } else { None }
-        })
+        self.iter().filter_map(|k| k.as_const())
     }
 
     #[inline]
@@ -400,31 +410,21 @@ impl<'tcx> InternalSubsts<'tcx> {
     #[inline]
     #[track_caller]
     pub fn type_at(&self, i: usize) -> Ty<'tcx> {
-        if let GenericArgKind::Type(ty) = self[i].unpack() {
-            ty
-        } else {
-            bug!("expected type for param #{} in {:?}", i, self);
-        }
+        self[i].as_type().unwrap_or_else(|| bug!("expected type for param #{} in {:?}", i, self))
     }
 
     #[inline]
     #[track_caller]
     pub fn region_at(&self, i: usize) -> ty::Region<'tcx> {
-        if let GenericArgKind::Lifetime(lt) = self[i].unpack() {
-            lt
-        } else {
-            bug!("expected region for param #{} in {:?}", i, self);
-        }
+        self[i]
+            .as_region()
+            .unwrap_or_else(|| bug!("expected region for param #{} in {:?}", i, self))
     }
 
     #[inline]
     #[track_caller]
     pub fn const_at(&self, i: usize) -> ty::Const<'tcx> {
-        if let GenericArgKind::Const(ct) = self[i].unpack() {
-            ct
-        } else {
-            bug!("expected const for param #{} in {:?}", i, self);
-        }
+        self[i].as_const().unwrap_or_else(|| bug!("expected const for param #{} in {:?}", i, self))
     }
 
     #[inline]
diff --git a/compiler/rustc_mir_transform/src/function_item_references.rs b/compiler/rustc_mir_transform/src/function_item_references.rs
index 8601c1b2d71..f26c6de9648 100644
--- a/compiler/rustc_mir_transform/src/function_item_references.rs
+++ b/compiler/rustc_mir_transform/src/function_item_references.rs
@@ -3,7 +3,7 @@ use rustc_errors::Applicability;
 use rustc_hir::def_id::DefId;
 use rustc_middle::mir::visit::Visitor;
 use rustc_middle::mir::*;
-use rustc_middle::ty::{self, EarlyBinder, GenericArgKind, PredicateKind, SubstsRef, Ty, TyCtxt};
+use rustc_middle::ty::{self, EarlyBinder, PredicateKind, SubstsRef, Ty, TyCtxt};
 use rustc_session::lint::builtin::FUNCTION_ITEM_REFERENCES;
 use rustc_span::{symbol::sym, Span};
 use rustc_target::spec::abi::Abi;
@@ -45,14 +45,12 @@ impl<'tcx> Visitor<'tcx> for FunctionItemRefChecker<'_, 'tcx> {
                 // Handle calls to `transmute`
                 if self.tcx.is_diagnostic_item(sym::transmute, def_id) {
                     let arg_ty = args[0].ty(self.body, self.tcx);
-                    for generic_inner_ty in arg_ty.walk() {
-                        if let GenericArgKind::Type(inner_ty) = generic_inner_ty.unpack() {
-                            if let Some((fn_id, fn_substs)) =
-                                FunctionItemRefChecker::is_fn_ref(inner_ty)
-                            {
-                                let span = self.nth_arg_span(&args, 0);
-                                self.emit_lint(fn_id, fn_substs, source_info, span);
-                            }
+                    for inner_ty in arg_ty.walk().filter_map(|arg| arg.as_type()) {
+                        if let Some((fn_id, fn_substs)) =
+                            FunctionItemRefChecker::is_fn_ref(inner_ty)
+                        {
+                            let span = self.nth_arg_span(&args, 0);
+                            self.emit_lint(fn_id, fn_substs, source_info, span);
                         }
                     }
                 } else {
@@ -82,24 +80,22 @@ impl<'tcx> FunctionItemRefChecker<'_, 'tcx> {
                 let arg_defs = self.tcx.fn_sig(def_id).subst_identity().skip_binder().inputs();
                 for (arg_num, arg_def) in arg_defs.iter().enumerate() {
                     // For all types reachable from the argument type in the fn sig
-                    for generic_inner_ty in arg_def.walk() {
-                        if let GenericArgKind::Type(inner_ty) = generic_inner_ty.unpack() {
-                            // If the inner type matches the type bound by `Pointer`
-                            if inner_ty == bound_ty {
-                                // Do a substitution using the parameters from the callsite
-                                let subst_ty = EarlyBinder(inner_ty).subst(self.tcx, substs_ref);
-                                if let Some((fn_id, fn_substs)) =
-                                    FunctionItemRefChecker::is_fn_ref(subst_ty)
-                                {
-                                    let mut span = self.nth_arg_span(args, arg_num);
-                                    if span.from_expansion() {
-                                        // The operand's ctxt wouldn't display the lint since it's inside a macro so
-                                        // we have to use the callsite's ctxt.
-                                        let callsite_ctxt = span.source_callsite().ctxt();
-                                        span = span.with_ctxt(callsite_ctxt);
-                                    }
-                                    self.emit_lint(fn_id, fn_substs, source_info, span);
+                    for inner_ty in arg_def.walk().filter_map(|arg| arg.as_type()) {
+                        // If the inner type matches the type bound by `Pointer`
+                        if inner_ty == bound_ty {
+                            // Do a substitution using the parameters from the callsite
+                            let subst_ty = EarlyBinder(inner_ty).subst(self.tcx, substs_ref);
+                            if let Some((fn_id, fn_substs)) =
+                                FunctionItemRefChecker::is_fn_ref(subst_ty)
+                            {
+                                let mut span = self.nth_arg_span(args, arg_num);
+                                if span.from_expansion() {
+                                    // The operand's ctxt wouldn't display the lint since it's inside a macro so
+                                    // we have to use the callsite's ctxt.
+                                    let callsite_ctxt = span.source_callsite().ctxt();
+                                    span = span.with_ctxt(callsite_ctxt);
                                 }
+                                self.emit_lint(fn_id, fn_substs, source_info, span);
                             }
                         }
                     }
diff --git a/compiler/rustc_symbol_mangling/src/typeid/typeid_itanium_cxx_abi.rs b/compiler/rustc_symbol_mangling/src/typeid/typeid_itanium_cxx_abi.rs
index 262e8546a5d..a9152b8113f 100644
--- a/compiler/rustc_symbol_mangling/src/typeid/typeid_itanium_cxx_abi.rs
+++ b/compiler/rustc_symbol_mangling/src/typeid/typeid_itanium_cxx_abi.rs
@@ -814,16 +814,10 @@ fn transform_substs<'tcx>(
     substs: SubstsRef<'tcx>,
     options: TransformTyOptions,
 ) -> SubstsRef<'tcx> {
-    let substs = substs.iter().map(|subst| {
-        if let GenericArgKind::Type(ty) = subst.unpack() {
-            if is_c_void_ty(tcx, ty) {
-                tcx.mk_unit().into()
-            } else {
-                transform_ty(tcx, ty, options).into()
-            }
-        } else {
-            subst
-        }
+    let substs = substs.iter().map(|subst| match subst.unpack() {
+        GenericArgKind::Type(ty) if is_c_void_ty(tcx, ty) => tcx.mk_unit().into(),
+        GenericArgKind::Type(ty) => transform_ty(tcx, ty, options).into(),
+        _ => subst,
     });
     tcx.mk_substs_from_iter(substs)
 }
diff --git a/src/bootstrap/builder.rs b/src/bootstrap/builder.rs
index 3d3f991bffa..0d2d512b4b2 100644
--- a/src/bootstrap/builder.rs
+++ b/src/bootstrap/builder.rs
@@ -1589,8 +1589,8 @@ impl<'a> Builder<'a> {
         // which adds to the runtime dynamic loader path when looking for
         // dynamic libraries. We use this by default on Unix platforms to ensure
         // that our nightlies behave the same on Windows, that is they work out
-        // of the box. This can be disabled, of course, but basically that's why
-        // we're gated on RUSTC_RPATH here.
+        // of the box. This can be disabled by setting `rpath = false` in `[rust]`
+        // table of `config.toml`
         //
         // Ok, so the astute might be wondering "why isn't `-C rpath` used
         // here?" and that is indeed a good question to ask. This codegen
diff --git a/src/doc/rustc/src/platform-support/loongarch-linux.md b/src/doc/rustc/src/platform-support/loongarch-linux.md
index d7d31d8724c..16ccaf46b2f 100644
--- a/src/doc/rustc/src/platform-support/loongarch-linux.md
+++ b/src/doc/rustc/src/platform-support/loongarch-linux.md
@@ -15,6 +15,8 @@ While the integer base ABI is implied by the machine field, the floating po
 |          f32           | The base ABI uses 32-bit FPRs for parameter passing. (lp64f)|
 |          sf            | The base ABI uses no FPR for parameter passing. (lp64s)     |
 
+<br>
+
 |`ABI type(Base ABI/ABI extension)`| `C library` | `kernel` |          `target tuple`          |
 |----------------------------------|-------------|----------|----------------------------------|
 |           lp64d/base             |   glibc     |  linux   | loongarch64-unknown-linux-gnu |
diff --git a/src/tools/compiletest/src/runtest.rs b/src/tools/compiletest/src/runtest.rs
index 1a4e9b58383..0c17ae79808 100644
--- a/src/tools/compiletest/src/runtest.rs
+++ b/src/tools/compiletest/src/runtest.rs
@@ -1900,8 +1900,11 @@ impl<'test> TestCx<'test> {
         // Use a single thread for efficiency and a deterministic error message order
         rustc.arg("-Zthreads=1");
 
-        // In stage 0, make sure we use `stage0-sysroot` instead of the bootstrap sysroot.
-        rustc.arg("--sysroot").arg(&self.config.sysroot_base);
+        // Optionally prevent default --sysroot if specified in test compile-flags.
+        if !self.props.compile_flags.iter().any(|flag| flag.starts_with("--sysroot")) {
+            // In stage 0, make sure we use `stage0-sysroot` instead of the bootstrap sysroot.
+            rustc.arg("--sysroot").arg(&self.config.sysroot_base);
+        }
 
         // Optionally prevent default --target if specified in test compile-flags.
         let custom_target = self.props.compile_flags.iter().any(|x| x.starts_with("--target"));