diff --git a/Library/Homebrew/cmd/gist-logs.rb b/Library/Homebrew/cmd/gist-logs.rb
index 6986f6160f..b5cc85f0da 100644
--- a/Library/Homebrew/cmd/gist-logs.rb
+++ b/Library/Homebrew/cmd/gist-logs.rb
@@ -82,7 +82,7 @@ module Homebrew
 
   def brief_build_info(f)
     build_time_str = f.logs.ctime.strftime("%Y-%m-%d %H:%M:%S")
-    s = <<~EOS
+    s = +<<~EOS
       Homebrew build logs for #{f.full_name} on #{OS_VERSION}
     EOS
     if args.with_hostname?