diff --git a/lib/vagrant/config/loader.rb b/lib/vagrant/config/loader.rb
index 2ebd339a1..e3f80a579 100644
--- a/lib/vagrant/config/loader.rb
+++ b/lib/vagrant/config/loader.rb
@@ -209,10 +209,15 @@ module Vagrant
             @logger.error("Vagrantfile load error: #{e.message}")
             @logger.error(e.backtrace.join("\n"))
 
+            line = "(unknown)"
+            if e.backtrace && e.backtrace[0]
+              line = e.backtrace[0].split(":")[1]
+            end
+
             # Report the generic exception
             raise Errors::VagrantfileLoadError,
               path: path,
-              line: e.backtrace[0].split(':')[1],
+              line: line,
               exception_class: e.class,
               message: e.message
           end
diff --git a/plugins/kernel_v2/config/vm.rb b/plugins/kernel_v2/config/vm.rb
index ed4e750fb..294a63e19 100644
--- a/plugins/kernel_v2/config/vm.rb
+++ b/plugins/kernel_v2/config/vm.rb
@@ -449,11 +449,18 @@ module VagrantPlugins
             end
           rescue Exception => e
             @logger.error("Vagrantfile load error: #{e.message}")
+            @logger.error(e.inspect)
+            @logger.error(e.message)
             @logger.error(e.backtrace.join("\n"))
 
+            line = "(unknown)"
+            if e.backtrace && e.backtrace[0]
+              line = e.backtrace[0].split(":")[1]
+            end
+
             raise Vagrant::Errors::VagrantfileLoadError,
               path: "<provider config: #{name}>",
-              line: e.backtrace[0].split(':')[1],
+              line: line,
               exception_class: e.class,
               message: e.message
           end