Auto merge of #38499 - alexcrichton:rollup, r=alexcrichton

Rollup of 29 pull requests

- Successful merges: #37761, #38006, #38131, #38150, #38158, #38171, #38208, #38215, #38236, #38245, #38289, #38302, #38315, #38346, #38388, #38395, #38398, #38418, #38432, #38451, #38463, #38468, #38470, #38471, #38472, #38478, #38486, #38493, #38498
- Failed merges: #38271, #38483

1 files changed, 7 insertions, 6 deletions

diff --git a/src/libsyntax/print/pprust.rs b/src/libsyntax/print/pprust.rs
index c28b9d00501..22e8391de93 100644
--- a/src/libsyntax/print/pprust.rs
+++ b/src/libsyntax/print/pprust.rs
@@ -2349,7 +2349,9 @@ impl<'a> State<'a> {
 
             try!(self.print_ident(segment.identifier));
 
-            try!(self.print_path_parameters(&segment.parameters, colons_before_params));
+            if let Some(ref parameters) = segment.parameters {
+                try!(self.print_path_parameters(parameters, colons_before_params))
+            }
         }
 
         Ok(())
@@ -2373,7 +2375,10 @@ impl<'a> State<'a> {
         try!(word(&mut self.s, "::"));
         let item_segment = path.segments.last().unwrap();
         try!(self.print_ident(item_segment.identifier));
-        self.print_path_parameters(&item_segment.parameters, colons_before_params)
+        match item_segment.parameters {
+            Some(ref parameters) => self.print_path_parameters(parameters, colons_before_params),
+            None => Ok(()),
+        }
     }
 
     fn print_path_parameters(&mut self,
@@ -2381,10 +2386,6 @@ impl<'a> State<'a> {
                              colons_before_params: bool)
                              -> io::Result<()>
     {
-        if parameters.is_empty() {
-            return Ok(());
-        }
-
         if colons_before_params {
             try!(word(&mut self.s, "::"))
         }