Initial support for dynamically linked crates

3 files changed, 45 insertions, 5 deletions

diff --git a/compiler/rustc_ast_pretty/src/pprust/mod.rs b/compiler/rustc_ast_pretty/src/pprust/mod.rs
index 551506f2aef..a05e2bd6a5d 100644
--- a/compiler/rustc_ast_pretty/src/pprust/mod.rs
+++ b/compiler/rustc_ast_pretty/src/pprust/mod.rs
@@ -7,7 +7,9 @@ use std::borrow::Cow;
 use rustc_ast as ast;
 use rustc_ast::token::{Token, TokenKind};
 use rustc_ast::tokenstream::{TokenStream, TokenTree};
-pub use state::{AnnNode, Comments, PpAnn, PrintState, State, print_crate};
+pub use state::{
+    AnnNode, Comments, PpAnn, PrintState, State, print_crate, print_crate_as_interface,
+};
 
 /// Print the token kind precisely, without converting `$crate` into its respective crate name.
 pub fn token_kind_to_string(tok: &TokenKind) -> Cow<'static, str> {
diff --git a/compiler/rustc_ast_pretty/src/pprust/state.rs b/compiler/rustc_ast_pretty/src/pprust/state.rs
index 28d5eb87c27..0990c9b27eb 100644
--- a/compiler/rustc_ast_pretty/src/pprust/state.rs
+++ b/compiler/rustc_ast_pretty/src/pprust/state.rs
@@ -221,6 +221,7 @@ pub struct State<'a> {
     pub s: pp::Printer,
     comments: Option<Comments<'a>>,
     ann: &'a (dyn PpAnn + 'a),
+    is_sdylib_interface: bool,
 }
 
 const INDENT_UNIT: isize = 4;
@@ -237,9 +238,36 @@ pub fn print_crate<'a>(
     edition: Edition,
     g: &AttrIdGenerator,
 ) -> String {
+    let mut s = State {
+        s: pp::Printer::new(),
+        comments: Some(Comments::new(sm, filename, input)),
+        ann,
+        is_sdylib_interface: false,
+    };
+
+    print_crate_inner(&mut s, krate, is_expanded, edition, g);
+    s.s.eof()
+}
+
+pub fn print_crate_as_interface(
+    krate: &ast::Crate,
+    edition: Edition,
+    g: &AttrIdGenerator,
+) -> String {
     let mut s =
-        State { s: pp::Printer::new(), comments: Some(Comments::new(sm, filename, input)), ann };
+        State { s: pp::Printer::new(), comments: None, ann: &NoAnn, is_sdylib_interface: true };
 
+    print_crate_inner(&mut s, krate, false, edition, g);
+    s.s.eof()
+}
+
+fn print_crate_inner<'a>(
+    s: &mut State<'a>,
+    krate: &ast::Crate,
+    is_expanded: bool,
+    edition: Edition,
+    g: &AttrIdGenerator,
+) {
     // We need to print shebang before anything else
     // otherwise the resulting code will not compile
     // and shebang will be useless.
@@ -282,8 +310,7 @@ pub fn print_crate<'a>(
         s.print_item(item);
     }
     s.print_remaining_comments();
-    s.ann.post(&mut s, AnnNode::Crate(krate));
-    s.s.eof()
+    s.ann.post(s, AnnNode::Crate(krate));
 }
 
 /// Should two consecutive tokens be printed with a space between them?
@@ -1111,7 +1138,7 @@ impl<'a> PrintState<'a> for State<'a> {
 
 impl<'a> State<'a> {
     pub fn new() -> State<'a> {
-        State { s: pp::Printer::new(), comments: None, ann: &NoAnn }
+        State { s: pp::Printer::new(), comments: None, ann: &NoAnn, is_sdylib_interface: false }
     }
 
     fn commasep_cmnt<T, F, G>(&mut self, b: Breaks, elts: &[T], mut op: F, mut get_span: G)
diff --git a/compiler/rustc_ast_pretty/src/pprust/state/item.rs b/compiler/rustc_ast_pretty/src/pprust/state/item.rs
index 1e02ac8fd5d..70cf2f2a459 100644
--- a/compiler/rustc_ast_pretty/src/pprust/state/item.rs
+++ b/compiler/rustc_ast_pretty/src/pprust/state/item.rs
@@ -160,6 +160,10 @@ impl<'a> State<'a> {
 
     /// Pretty-prints an item.
     pub(crate) fn print_item(&mut self, item: &ast::Item) {
+        if self.is_sdylib_interface && item.span.is_dummy() {
+            // Do not print prelude for interface files.
+            return;
+        }
         self.hardbreak_if_not_bol();
         self.maybe_print_comment(item.span.lo());
         self.print_outer_attributes(&item.attrs);
@@ -682,6 +686,13 @@ impl<'a> State<'a> {
             self.print_contract(contract);
         }
         if let Some((body, (cb, ib))) = body_cb_ib {
+            if self.is_sdylib_interface {
+                self.word(";");
+                self.end(ib); // end inner head-block
+                self.end(cb); // end outer head-block
+                return;
+            }
+
             self.nbsp();
             self.print_block_with_attrs(body, attrs, cb, ib);
         } else {