From f13adc5f9d50f66b3b86589c35e49c92af807f23 Mon Sep 17 00:00:00 2001
From: Vadim Petrochenkov <vadim.petrochenkov@gmail.com>
Date: Wed, 2 Oct 2019 02:47:36 +0300
Subject: [PATCH] metadata: Remove `CrateMetadata::host_lib`

It was only used for retreiving edition, which was a bug.
In case of dual proc macros the edition should be taken from the target crate version, like any other metadata.
---
 src/librustc_metadata/creader.rs | 1 -
 src/librustc_metadata/cstore.rs  | 2 --
 src/librustc_metadata/decoder.rs | 7 +------
 3 files changed, 1 insertion(+), 9 deletions(-)

diff --git a/src/librustc_metadata/creader.rs b/src/librustc_metadata/creader.rs
index ea1b746dc07fe..f2980941082f4 100644
--- a/src/librustc_metadata/creader.rs
+++ b/src/librustc_metadata/creader.rs
@@ -271,7 +271,6 @@ impl<'a> CrateLoader<'a> {
             },
             private_dep,
             span,
-            host_lib,
             raw_proc_macros
         };
 
diff --git a/src/librustc_metadata/cstore.rs b/src/librustc_metadata/cstore.rs
index ed43aad38be0a..d8bbe23b8ecbc 100644
--- a/src/librustc_metadata/cstore.rs
+++ b/src/librustc_metadata/cstore.rs
@@ -28,7 +28,6 @@ pub use crate::cstore_impl::{provide, provide_extern};
 pub type CrateNumMap = IndexVec<CrateNum, CrateNum>;
 
 pub use rustc_data_structures::sync::MetadataRef;
-use crate::creader::Library;
 use syntax_pos::Span;
 use proc_macro::bridge::client::ProcMacro;
 
@@ -85,7 +84,6 @@ pub struct CrateMetadata {
     /// for purposes of the 'exported_private_dependencies' lint
     pub private_dep: bool,
 
-    pub host_lib: Option<Library>,
     pub span: Span,
 
     pub raw_proc_macros: Option<&'static [ProcMacro]>,
diff --git a/src/librustc_metadata/decoder.rs b/src/librustc_metadata/decoder.rs
index 9fcc310154599..6681cf3052f2b 100644
--- a/src/librustc_metadata/decoder.rs
+++ b/src/librustc_metadata/decoder.rs
@@ -543,18 +543,13 @@ impl<'a, 'tcx> CrateMetadata {
                 name, SyntaxExtensionKind::Bang(Box::new(BangProcMacro { client })), Vec::new()
             )
         };
-        let edition = if sess.opts.debugging_opts.dual_proc_macros {
-            self.host_lib.as_ref().unwrap().metadata.get_root().edition
-        } else {
-            self.root.edition
-        };
 
         SyntaxExtension::new(
             &sess.parse_sess,
             kind,
             self.get_span(id, sess),
             helper_attrs,
-            edition,
+            self.root.edition,
             Symbol::intern(name),
             &self.get_attributes(&self.entry(id), sess),
         )