diff --git a/tools/tools/git/mfc-candidates.lua b/tools/tools/git/mfc-candidates.lua
--- a/tools/tools/git/mfc-candidates.lua
+++ b/tools/tools/git/mfc-candidates.lua
@@ -7,6 +7,9 @@
 -- "MFC from" branch and do not have a corresponding "cherry picked from"
 -- commit in the "MFC to" branch.
 
+-- Global state
+local verbose = 0
+
 -- Execute a command and return its output.  A final newline is stripped,
 -- similar to sh.
 local function exec_command(command)
@@ -102,9 +105,6 @@
 	return result
 end
 
--- Global state
-verbose = 0
-
 local function params(from_branch, to_branch, author)
 	print("from:             " .. from_branch)
 	print("to:               " .. to_branch)
@@ -204,7 +204,7 @@
 	local result_hashes = set_difference(from_hashes, to_hashes)
 
 	if exclude_file then
-		exclude_hashes = read_exclude(exclude_file)
+		local exclude_hashes = read_exclude(exclude_file)
 		result_hashes = set_difference(result_hashes, exclude_hashes)
 	end