Auto merge of servo#224 - servo:morestack, r=SimonSapin

procedural-masquerade: Give more stack to procedural-masquerade macros.

This is a prospective fix for servo/servo#21038.

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Author: bors-servo

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "cssparser"
-version = "0.23.9"
+version = "0.23.10"
 authors = [ "Simon Sapin <simon.sapin@exyr.org>" ]
 
 description = "Rust implementation of CSS Syntax Level 3"

procedural-masquerade/lib.rs

@@ -177,8 +177,15 @@ macro_rules! define_proc_macros {
                 fn wrapped($input: &str) -> String {
                     $body
                 }
+
+                // syn uses a huge amount of stack in debug mode.
                 let derive_input_string = derive_input.to_string();
-                wrapped($crate::_extract_input(&derive_input_string)).parse().unwrap()
+                let handle =
+                    ::std::thread::Builder::new().stack_size(128 * 1024 * 1024).spawn(move || {
+                        wrapped($crate::_extract_input(&derive_input_string))
+                    }).unwrap();
+
+                handle.join().unwrap().parse().unwrap()
             }
         )+
     }