Update rules to be with headers

Author: ehuss

src/destructors.md

@@ -426,19 +426,18 @@ let x = (&temp()).use_temp();  // ERROR
 r[destructors.forget]
 ## Not running destructors
 
+r[destructors.manually-preventing]
 ### Manually preventing destructors
 
-r[destructors.manually-preventing]
 [`std::mem::forget`] can be used to prevent the destructor of a variable from being run,
 and [`std::mem::ManuallyDrop`] provides a wrapper to prevent a
 variable or field from being dropped automatically.
 
 > Note: Preventing a destructor from being run via [`std::mem::forget`] or other means is safe even if it has a type that isn't `'static`.
 > Besides the places where destructors are guaranteed to run as defined by this document, types may *not* safely rely on a destructor being run for soundness.
 
-### Process termination without unwinding
-
 r[destructors.process-termination]
+### Process termination without unwinding
 
 There are some ways to terminate the process without [unwinding], in which case
 destructors will not be run.

src/items/functions.md

@@ -253,9 +253,8 @@ extern "C" fn new_i32() -> i32 { 0 }
 let fptr: extern "C" fn() -> i32 = new_i32;
 ```
 
-### Unwinding
-
 r[items.fn.extern.unwind]
+### Unwinding
 
 r[items.fn.extern.unwind.intro]
 Most ABI strings come in two variants, one with an `-unwind` suffix and one without.

src/linkage.md

@@ -275,9 +275,8 @@ Passing `rlib`s directly into your foreign linker is currently unsupported.
 >  Rust code compiled or linked with a different instance of the Rust runtime counts as a
 > "foreign code" for the purpose of this section.
 
-### Prohibited linkage and unwinding
-
 r[link.unwinding]
+### Prohibited linkage and unwinding
 
 r[link.unwinding.consistency]
 If you are *not* using `rustc` to link Rust files, you must take care to ensure that unwinding is

src/panic.md

@@ -1,6 +1,5 @@
-# Panic
-
 r[panic]
+# Panic
 
 r[panic.intro]
 Rust provides a mechanism to prevent a function from returning normally, and instead "panic," which is a response to an error condition that is typically not expected to be recoverable within the context in which the error is encountered.
@@ -17,9 +16,8 @@ There are also language features that provide a level of control over panic beha
 > [!NOTE]
 > The standard library provides the capability to explicitly panic via the [`panic!` macro][panic!].
 
-## Unwinding
-
 r[panic.unwind]
+## Unwinding
 
 r[panic.unwind.intro]
 Panicking may either be recoverable or non-recoverable, though it can be configured (via `panic=abort`) to always be non-recoverable. (The converse is not true: `panic=unwind` does not guarantee that all panics are recoverable, only that panicking via the `panic!` macro and similar standard library mechanisms is recoverable.)
@@ -33,9 +31,8 @@ When panic recovery occurs, the runtime "unwinds" Rust frames, just as C++'s `th
 > [!NOTE]
 > The standard library provides two mechanisms for recovering from a panic, [`std::panic::catch_unwind`] (which enables recovery within the panicking thread) and [`std::thread::spawn`] (which automatically sets up panic recovery for the spawned thread so that other threads may continue running).
 
-### Unwinding across FFI boundaries
-
 r[panic.unwind.ffi]
+### Unwinding across FFI boundaries
 
 r[panic.unwind.ffi.intro]
 It is possible to unwind across FFI boundaries using an [appropriate ABI declaration][unwind-abi]. While useful in certain cases, this creates unique opportunities for undefined behavior, especially when multiple language runtimes are involved.
@@ -58,9 +55,8 @@ Catching a foreign unwinding operation (such as a C++ exception) using [`std::pa
 r[panic.unwind.ffi.dispose-panic]
 There are currently no guarantees about the behavior that occurs when a foreign runtime attempts to dispose of, or rethrow, a Rust `panic` payload. In other words, an unwind originated from a Rust runtime must either lead to termination of the process or be caught by the same runtime.
 
-## Panic runtimes
-
 r[panic.runtime]
+## Panic runtimes
 
 The actual behavior and implementation of `panic!` is controlled by the _panic runtime_.