commit e1da66f0948bee5ef3a4f57f959a0a0442dd3c3a
author David Tolnay <dtolnay@gmail.com> Mon Apr 22 14:41:06 2019 -0700
committer David Tolnay <dtolnay@gmail.com> Mon Apr 22 14:42:16 2019 -0700
tree 2a5aa4eb8b0cf3638032fbddb673cab9dccc01c1
parent b8a68e462d38fbaa99599f9c41ff10920c6a4cd3

Require rustc that can support assoc consts for peek_any

build.rs

diff --git a/build.rs b/build.rs
index 644bf75..2b2a419 100644
--- a/build.rs
+++ b/build.rs
@@ -15,6 +15,10 @@
         println!("cargo:rustc-cfg=syn_can_use_thread_id");
     }
 
+    if compiler.minor >= 20 {
+        println!("cargo:rustc-cfg=syn_can_use_associated_constants");
+    }
+
     // Macro modularization allows re-exporting the `quote!` macro in 1.30+.
     if compiler.minor >= 30 {
         println!("cargo:rustc-cfg=syn_can_call_macro_by_path");