Don't load all extern crates unconditionally

Instead, only load the crates that are linked to with intra-doc links.

This doesn't help very much with any of rustdoc's fundamental issues
with freezing the resolver, but it at least fixes a stable-to-stable
regression, and makes the crate loading model somewhat more consistent
with rustc's.

1 files changed, 2 insertions, 2 deletions

diff --git a/src/tools/compiletest/src/header.rs b/src/tools/compiletest/src/header.rs
index 83ea676e8f4..531a23d76a2 100644
--- a/src/tools/compiletest/src/header.rs
+++ b/src/tools/compiletest/src/header.rs
@@ -708,8 +708,8 @@ impl Config {
         self.parse_name_value_directive(line, "aux-crate").map(|r| {
             let mut parts = r.trim().splitn(2, '=');
             (
-                parts.next().expect("aux-crate name").to_string(),
-                parts.next().expect("aux-crate value").to_string(),
+                parts.next().expect("missing aux-crate name (e.g. log=log.rs)").to_string(),
+                parts.next().expect("missing aux-crate value (e.g. log=log.rs)").to_string(),
             )
         })
     }