From b319715456c08097f2cd936da309ed6e8aec2843 Mon Sep 17 00:00:00 2001
From: Wesley Wiser <wwiser@gmail.com>
Date: Thu, 22 Nov 2018 12:56:15 -0500
Subject: [PATCH] Disable the self-profiler unless the `-Z self-profile` flag
 is set

Related to #51648
---
 src/librustc/session/mod.rs | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/src/librustc/session/mod.rs b/src/librustc/session/mod.rs
index d688d93b8084..1187c53305d1 100644
--- a/src/librustc/session/mod.rs
+++ b/src/librustc/session/mod.rs
@@ -826,8 +826,10 @@ impl Session {
     }
 
     pub fn profiler<F: FnOnce(&mut SelfProfiler) -> ()>(&self, f: F) {
-        let mut profiler = self.self_profiling.borrow_mut();
-        f(&mut profiler);
+        if self.opts.debugging_opts.self_profile {
+            let mut profiler = self.self_profiling.borrow_mut();
+            f(&mut profiler);
+        }
     }
 
     pub fn print_profiler_results(&self) {