From b417701ac118d4864e3bd07b700f3c8af724b199 Mon Sep 17 00:00:00 2001
From: Niko Matsakis <niko@alum.mit.edu>
Date: Wed, 6 Jun 2018 16:20:47 -0400
Subject: add an explanatory comment

---
 src/libsyntax/parse/parser.rs | 5 +++++
 1 file changed, 5 insertions(+)

(limited to 'src/libsyntax/parse')

diff --git a/src/libsyntax/parse/parser.rs b/src/libsyntax/parse/parser.rs
index 91bf1f6a953..f6692a30491 100644
--- a/src/libsyntax/parse/parser.rs
+++ b/src/libsyntax/parse/parser.rs
@@ -6151,6 +6151,11 @@ impl<'a> Parser<'a> {
     pub fn submod_path_from_attr(attrs: &[Attribute], dir_path: &Path) -> Option<PathBuf> {
         if let Some(s) = attr::first_attr_value_str_by_name(attrs, "path") {
             let s = s.as_str();
+
+            // On windows, the base path might have the form
+            // `\\?\foo\bar` in which case it does not tolerate
+            // mixed `/` and `\` separators, so canonicalize
+            // `/` to `\`.
             #[cfg(windows)]
             let s = s.replace("/", "\\");
             Some(dir_path.join(s))
-- 
cgit 1.4.1-3-g733a5