diff --git a/app/models/notice.rb b/app/models/notice.rb
index 9751464..5310b1f 100644
--- a/app/models/notice.rb
+++ b/app/models/notice.rb
@@ -96,7 +96,7 @@ class Notice
 
   def backtrace
     # If gems are vendored into project, treat vendored gem dir as [GEM_ROOT]
-    (read_attribute(:backtrace) || {}).map do |line|
+    (read_attribute(:backtrace) || []).map do |line|
       # Changes "[PROJECT_ROOT]/rubygems/ruby/1.9.1/gems" to "[GEM_ROOT]/gems"
       line.merge 'file' => line['file'].gsub(/\[PROJECT_ROOT\]\/.*\/ruby\/[0-9.]+\/gems/, '[GEM_ROOT]/gems')
     end
--
libgit2 0.21.2