Fix typetree generation for differentiated functions

[ZuseZ4]

Further improvements after #158278
This fixes a test failure on main (encountered while working on the PR above) in tests/codegen-llvm/autodiff/autodiffv2.rs.

Further improvements are split out into #158440

[rustbot]

r? @mu001999

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[ZuseZ4]

r? oli-obk

[rustbot]

⚠️ Warning ⚠️

• Some commits in this PR modify submodules.

  If this was not intentional, see I changed a submodule on accident in the rustc dev guide.

[rust-log-analyzer]

The job tidy failed! Check out the build log: (web) (plain enhanced) (plain)

Click to see the possible cause of the failure (guessed by this bot)

Diff in /checkout/compiler/rustc_codegen_ssa/src/traits/builder.rs:2:
 use std::ops::Deref;
 
 use rustc_abi::{Align, Scalar, Size, WrappingRange};
-use rustc_ast::expand::typetree::{TypeTree, FncTree};
+use rustc_ast::expand::typetree::{FncTree, TypeTree};
 use rustc_hir::attrs::AttributeKind;
 use rustc_middle::middle::codegen_fn_attrs::CodegenFnAttrs;
 use rustc_middle::mir;
Diff in /checkout/compiler/rustc_codegen_ssa/src/traits/builder.rs:525:
             with_no_trimmed_paths!({
                 eprintln!("memcpy ty = {:?}", layout.ty);
             });
-            let fnc_tree = FncTree {
-                args: vec![tt.clone(), tt],
-                ret: TypeTree::new(),
-            };
+            let fnc_tree = FncTree { args: vec![tt.clone(), tt], ret: TypeTree::new() };
             let bytes = self.const_usize(layout.size.bytes());
             self.memcpy(dst.llval, dst.align, src.llval, src.align, bytes, flags, Some(fnc_tree));
         }
Diff in /checkout/compiler/rustc_codegen_llvm/src/typetree.rs:183:
         let ret_attr = llvm::CreateAttrStringValueFromCStr(llcx, &c_attr_name, &c_str);
 
         if unsafe { llvm::LLVMRustIsIntrinsicCall(fn_def) } {
-            attributes::apply_to_callsite(
-                fn_def,
-                llvm::AttributePlace::ReturnValue,
-                &[ret_attr],
-            );
+            attributes::apply_to_callsite(fn_def, llvm::AttributePlace::ReturnValue, &[ret_attr]);
         } else {
             attributes::apply_to_llfn(fn_def, llvm::AttributePlace::ReturnValue, &[ret_attr]);
         }
fmt: checked 6938 files
Bootstrap failed while executing `test src/tools/tidy tidyselftest --extra-checks=py,cpp,js,spellcheck`
Build completed unsuccessfully in 0:00:51
  local time: Thu Jun 25 00:11:47 UTC 2026

[ZuseZ4]

Doesn't look like Github CI will merge the previous PR anytime soon, so I'll add a few more features here in the meantime.