Auto merge of #77224 - RalfJung:rollup-hdvb96c, r=RalfJung

Rollup of 12 pull requests

Successful merges:

 - #75454 (Explicitly document the size guarantees that Option makes.)
 - #76631 (Add `x.py setup`)
 - #77076 (Add missing code examples on slice iter types)
 - #77093 (merge `need_type_info_err(_const)`)
 - #77122 (Add `#![feature(const_fn_floating_point_arithmetic)]`)
 - #77127 (Update mdBook)
 - #77161 (Remove TrustedLen requirement from BuilderMethods::switch)
 - #77166 (update Miri)
 - #77181 (Add doc alias for pointer primitive)
 - #77204 (Remove stray word from `ClosureKind::extends` docs)
 - #77207 (Rename `whence` to `span`)
 - #77211 (Remove unused #[allow(...)] statements from compiler/)

Failed merges:

 - #77170 (Remove `#[rustc_allow_const_fn_ptr]` and add `#![feature(const_fn_fn_ptr_basics)]`)

r? `@ghost`

5 files changed, 1 insertions, 8 deletions

diff --git a/compiler/rustc_codegen_llvm/src/builder.rs b/compiler/rustc_codegen_llvm/src/builder.rs
index 23a3be1a2f2..0c172dc33ba 100644
--- a/compiler/rustc_codegen_llvm/src/builder.rs
+++ b/compiler/rustc_codegen_llvm/src/builder.rs
@@ -21,7 +21,6 @@ use rustc_target::abi::{self, Align, Size};
 use rustc_target::spec::{HasTargetSpec, Target};
 use std::borrow::Cow;
 use std::ffi::CStr;
-use std::iter::TrustedLen;
 use std::ops::{Deref, Range};
 use std::ptr;
 use tracing::debug;
@@ -179,7 +178,7 @@ impl BuilderMethods<'a, 'tcx> for Builder<'a, 'll, 'tcx> {
         &mut self,
         v: &'ll Value,
         else_llbb: &'ll BasicBlock,
-        cases: impl ExactSizeIterator<Item = (u128, &'ll BasicBlock)> + TrustedLen,
+        cases: impl ExactSizeIterator<Item = (u128, &'ll BasicBlock)>,
     ) {
         let switch =
             unsafe { llvm::LLVMBuildSwitch(self.llbuilder, v, else_llbb, cases.len() as c_uint) };
@@ -931,7 +930,6 @@ impl BuilderMethods<'a, 'tcx> for Builder<'a, 'll, 'tcx> {
         unsafe { llvm::LLVMBuildSelect(self.llbuilder, cond, then_val, else_val, UNNAMED) }
     }
 
-    #[allow(dead_code)]
     fn va_arg(&mut self, list: &'ll Value, ty: &'ll Type) -> &'ll Value {
         unsafe { llvm::LLVMBuildVAArg(self.llbuilder, list, ty, UNNAMED) }
     }
diff --git a/compiler/rustc_codegen_llvm/src/common.rs b/compiler/rustc_codegen_llvm/src/common.rs
index 0b1cf03fa7e..0992410a728 100644
--- a/compiler/rustc_codegen_llvm/src/common.rs
+++ b/compiler/rustc_codegen_llvm/src/common.rs
@@ -1,5 +1,3 @@
-#![allow(non_camel_case_types, non_snake_case)]
-
 //! Code that is useful in various codegen modules.
 
 use crate::consts::{self, const_alloc_to_llvm};
diff --git a/compiler/rustc_codegen_llvm/src/debuginfo/metadata.rs b/compiler/rustc_codegen_llvm/src/debuginfo/metadata.rs
index 868eb74cf09..987149cb4c2 100644
--- a/compiler/rustc_codegen_llvm/src/debuginfo/metadata.rs
+++ b/compiler/rustc_codegen_llvm/src/debuginfo/metadata.rs
@@ -1845,7 +1845,6 @@ impl<'tcx> VariantInfo<'_, 'tcx> {
         None
     }
 
-    #[allow(dead_code)]
     fn is_artificial(&self) -> bool {
         match self {
             VariantInfo::Generator { .. } => true,
diff --git a/compiler/rustc_codegen_llvm/src/lib.rs b/compiler/rustc_codegen_llvm/src/lib.rs
index 456e9c7ce75..f14493e6043 100644
--- a/compiler/rustc_codegen_llvm/src/lib.rs
+++ b/compiler/rustc_codegen_llvm/src/lib.rs
@@ -12,7 +12,6 @@
 #![feature(in_band_lifetimes)]
 #![feature(nll)]
 #![feature(or_patterns)]
-#![feature(trusted_len)]
 #![recursion_limit = "256"]
 
 use back::write::{create_informational_target_machine, create_target_machine};
diff --git a/compiler/rustc_codegen_llvm/src/va_arg.rs b/compiler/rustc_codegen_llvm/src/va_arg.rs
index 54efa05aee8..22ed4dd7576 100644
--- a/compiler/rustc_codegen_llvm/src/va_arg.rs
+++ b/compiler/rustc_codegen_llvm/src/va_arg.rs
@@ -11,7 +11,6 @@ use rustc_middle::ty::layout::HasTyCtxt;
 use rustc_middle::ty::Ty;
 use rustc_target::abi::{Align, HasDataLayout, LayoutOf, Size};
 
-#[allow(dead_code)]
 fn round_pointer_up_to_alignment(
     bx: &mut Builder<'a, 'll, 'tcx>,
     addr: &'ll Value,