Rollup merge of #153776 - zetanumbers:curry-howard-dyn-thread-safe, r=JonathanBrouwer

Remove redundant `is_dyn_thread_safe` checks

Refactor uses of `FromDyn` to reduce number of redundant `is_dyn_thread_safe` checks by replacing `FromDyn::from` with `check_dyn_thread_safe` in tandem with existing `FromDyn::derive` so that the users would avoid redundancy in the future.

PR is split up into multiple commits for an easier review.

compiler/rustc_interface/src/util.rs

@@ -183,7 +183,6 @@ pub(crate) fn run_in_thread_pool_with_globals<
     use std::process;
 
     use rustc_data_structures::defer;
-    use rustc_data_structures::sync::FromDyn;
     use rustc_middle::ty::tls;
     use rustc_query_impl::break_query_cycles;
 
@@ -191,7 +190,7 @@ pub(crate) fn run_in_thread_pool_with_globals<
 
     let registry = sync::Registry::new(std::num::NonZero::new(threads).unwrap());
 
-    if !sync::is_dyn_thread_safe() {
+    let Some(proof) = sync::check_dyn_thread_safe() else {
         return run_in_thread_with_globals(
             thread_stack_size,
             edition,
@@ -204,9 +203,9 @@ pub(crate) fn run_in_thread_pool_with_globals<
                 f(current_gcx, jobserver_proxy)
             },
         );
-    }
+    };
 
-    let current_gcx = FromDyn::from(CurrentGcx::new());
+    let current_gcx = proof.derive(CurrentGcx::new());
     let current_gcx2 = current_gcx.clone();
 
     let proxy = Proxy::new();
@@ -278,7 +277,7 @@ pub(crate) fn run_in_thread_pool_with_globals<
     // `Send` in the parallel compiler.
     rustc_span::create_session_globals_then(edition, extra_symbols, Some(sm_inputs), || {
         rustc_span::with_session_globals(|session_globals| {
-            let session_globals = FromDyn::from(session_globals);
+            let session_globals = proof.derive(session_globals);
             builder
                 .build_scoped(
                     // Initialize each new worker thread when created.