From 7e3e9b2d01a82fc94cc8c9d19e623ab7d778f01a Mon Sep 17 00:00:00 2001
From: Alex Crichton <alex@alexcrichton.com>
Date: Thu, 1 Jun 2017 12:24:51 -0700
Subject: [PATCH] Ignore ENOTSUP in file locking on Linux too

Apparently there are some filesystems that return this!

Closes #4096
---
 src/cargo/util/flock.rs | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/src/cargo/util/flock.rs b/src/cargo/util/flock.rs
index 1be77b2d843..505a88a008a 100644
--- a/src/cargo/util/flock.rs
+++ b/src/cargo/util/flock.rs
@@ -271,10 +271,11 @@ fn acquire(config: &Config,
     match try() {
         Ok(()) => return Ok(()),
 
-        // Like above, where we ignore file locking on NFS mounts on Linux, we
-        // do the same on OSX here. Note that ENOTSUP is an OSX_specific
-        // constant.
-        #[cfg(target_os = "macos")]
+        // In addition to ignoring NFS which is commonly not working we also
+        // just ignore locking on filesystems that look like they don't
+        // implement file locking. We detect that here via the return value of
+        // locking (e.g. inspecting errno).
+        #[cfg(unix)]
         Err(ref e) if e.raw_os_error() == Some(libc::ENOTSUP) => return Ok(()),
 
         #[cfg(target_os = "linux")]