Merge pull request #412 from dtolnay/sort

Perform topological sort of structs earlier during type checking

gen/src/mod.rs

@@ -12,7 +12,6 @@ pub(super) mod include;
 mod namespace;
 mod nested;
 pub(super) mod out;
-mod toposort;
 mod write;
 
 pub(super) use self::error::Error;

gen/src/write.rs

@@ -1,7 +1,7 @@
 use crate::gen::block::Block;
 use crate::gen::nested::NamespaceEntries;
 use crate::gen::out::OutFile;
-use crate::gen::{builtin, include, toposort, Opt};
+use crate::gen::{builtin, include, Opt};
 use crate::syntax::atom::Atom::{self, *};
 use crate::syntax::symbol::Symbol;
 use crate::syntax::{
@@ -96,7 +96,7 @@ fn write_data_structures<'a>(out: &mut OutFile<'a>, apis: &'a [Api]) {
         }
     }
 
-    for strct in toposort::sort(apis, out.types) {
+    for strct in &out.types.toposorted_structs {
         out.next_section();
         if !out.types.cxx.contains(&strct.name.rust) {
             write_struct(out, strct);

syntax/mod.rs

@@ -20,6 +20,7 @@ pub mod report;
 pub mod set;
 pub mod symbol;
 mod tokens;
+mod toposort;
 pub mod types;
 
 use self::discriminant::Discriminant;

syntax/types.rs

@@ -3,7 +3,8 @@ use crate::syntax::improper::ImproperCtype;
 use crate::syntax::report::Errors;
 use crate::syntax::set::OrderedSet as Set;
 use crate::syntax::{
-    Api, Derive, Enum, ExternFn, ExternType, Impl, Pair, ResolvableName, Struct, Type, TypeAlias,
+    toposort, Api, Derive, Enum, ExternFn, ExternType, Impl, Pair, ResolvableName, Struct, Type,
+    TypeAlias,
 };
 use proc_macro2::Ident;
 use quote::ToTokens;
@@ -21,6 +22,7 @@ pub struct Types<'a> {
     pub explicit_impls: Set<&'a Impl>,
     pub resolutions: Map<&'a Ident, &'a Pair>,
     pub struct_improper_ctypes: UnorderedSet<&'a Ident>,
+    pub toposorted_structs: Vec<&'a Struct>,
 }
 
 impl<'a> Types<'a> {
@@ -35,6 +37,7 @@ impl<'a> Types<'a> {
         let mut explicit_impls = Set::new();
         let mut resolutions = Map::new();
         let struct_improper_ctypes = UnorderedSet::new();
+        let toposorted_structs = Vec::new();
 
         fn visit<'a>(all: &mut Set<&'a Type>, ty: &'a Type) {
             all.insert(ty);
@@ -205,8 +208,11 @@ impl<'a> Types<'a> {
             explicit_impls,
             resolutions,
             struct_improper_ctypes,
+            toposorted_structs,
         };
 
+        types.toposorted_structs = toposort::sort(apis, &types);
+
         let mut unresolved_structs: Vec<&Ident> = types.structs.keys().copied().collect();
         let mut new_information = true;
         while new_information {