Fix some compiler warnings

Also enables debug symbols in release profile by default. Until
Alacritty ships, there's going to be lots of perf analysis which needs
debug symbols.

The PriorityMutex low priority method was never used. Now it's just a
fair mutex.

1 files changed, 3 insertions, 0 deletions

diff --git a/Cargo.toml b/Cargo.toml
index c855e255..a8067ccb 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -25,3 +25,6 @@ gl_generator = "0.5"
 [dependencies.glutin]
 git = "https://github.com/jwilm/glutin"
 rev = "16ed800f68022a37203434bd3b542ff5400c1403"
+
+[profile.release]
+debug = true