Use more reasonable stack sizes and growth factors

Author: oli-obk

src/librustc/middle/recursion_limit.rs

@@ -20,8 +20,8 @@ use syntax::ast;
 
 use rustc_data_structures::sync::Once;
 
-const RED_ZONE: usize = 1024*1024; // 1MB
-const STACK_PER_RECURSION: usize = 8 * 1024 * 1024; // 8MB
+const RED_ZONE: usize = 100*1024; // 100k
+const STACK_PER_RECURSION: usize = 1 * 1024 * 1024; // 1MB
 
 /// Grows the stack on demand to prevent stack overflow. Call this in strategic locations
 /// to "break up" recursive calls. E.g. almost any call to `visit_expr` or equivalent can benefit

src/librustc_driver/driver.rs

@@ -91,7 +91,7 @@ pub fn spawn_thread_pool<F: FnOnce(config::Options) -> R + sync::Send, R: sync::
     let config = ThreadPoolBuilder::new()
         .num_threads(Session::query_threads_from_opts(&opts))
         .deadlock_handler(|| unsafe { ty::query::handle_deadlock() })
-        .stack_size(16 * 1024 * 1024);
+        .stack_size(::STACK_SIZE);
 
     let with_pool = move |pool: &ThreadPool| {
         pool.install(move || f(opts))

src/librustc_driver/lib.rs

@@ -1468,6 +1468,8 @@ fn parse_crate_attrs<'a>(sess: &'a Session, input: &Input) -> PResult<'a, Vec<as
     }
 }
 
+const STACK_SIZE: usize = 4 * 1024 * 1024; // 4MB
+
 /// Runs `f` in a suitable thread for running `rustc`; returns a `Result` with either the return
 /// value of `f` or -- if a panic occurs -- the panic value.
 ///
@@ -1477,8 +1479,6 @@ pub fn in_named_rustc_thread<F, R>(name: String, f: F) -> Result<R, Box<dyn Any
     where F: FnOnce() -> R + Send + 'static,
           R: Send + 'static,
 {
-    // Temporarily have stack size set to 16MB to deal with nom-using crates failing
-    const STACK_SIZE: usize = 16 * 1024 * 1024; // 16MB
 
     #[cfg(all(unix, not(target_os = "haiku")))]
     let spawn_thread = unsafe {