diff --git a/artiq/compiler/module.py b/artiq/compiler/module.py
index 80e44acd3..38bccda92 100644
--- a/artiq/compiler/module.py
+++ b/artiq/compiler/module.py
@@ -32,8 +32,6 @@ class Module:
         monomorphism_validator.visit(self.typedtree)
         escape_validator.visit(self.typedtree)
         self.artiq_ir = artiq_ir_generator.visit(self.typedtree)
-        print(self.artiq_ir[0])
-        print(self.artiq_ir[1])
         dead_code_eliminator.process(self.artiq_ir)
         local_access_validator.process(self.artiq_ir)
         self.llvm_ir = llvm_ir_generator.process(self.artiq_ir)
diff --git a/artiq/compiler/testbench/inferencer.py b/artiq/compiler/testbench/inferencer.py
index 64a24b39d..e6e73ea60 100644
--- a/artiq/compiler/testbench/inferencer.py
+++ b/artiq/compiler/testbench/inferencer.py
@@ -42,7 +42,7 @@ class Printer(algorithm.Visitor):
                                        ":{}".format(self.type_printer.name(node.type)))
 
 def main():
-    if sys.argv[1] == "+mono":
+    if len(sys.argv) > 1 and sys.argv[1] == "+mono":
         del sys.argv[1]
         monomorphize = True
     else:
diff --git a/artiq/compiler/transforms/llvm_ir_generator.py b/artiq/compiler/transforms/llvm_ir_generator.py
index 8749d3348..de7a75307 100644
--- a/artiq/compiler/transforms/llvm_ir_generator.py
+++ b/artiq/compiler/transforms/llvm_ir_generator.py
@@ -17,8 +17,9 @@ class LLVMIRGenerator:
         self.fixups = []
 
     def llty_of_type(self, typ, bare=False, for_return=False):
+        typ = typ.find()
         if types.is_tuple(typ):
-            return ll.LiteralStructType([self.llty_of_type(eltty) for eltty in typ.find().elts])
+            return ll.LiteralStructType([self.llty_of_type(eltty) for eltty in typ.elts])
         elif types.is_function(typ):
             envarg = ll.IntType(8).as_pointer()
             llty = ll.FunctionType(args=[envarg] +
diff --git a/artiq/compiler/validators/local_access.py b/artiq/compiler/validators/local_access.py
index 57fd8486c..fb68b54d4 100644
--- a/artiq/compiler/validators/local_access.py
+++ b/artiq/compiler/validators/local_access.py
@@ -97,16 +97,18 @@ class LocalAccessValidator:
                                 self._uninitialized_access(insn, var_name,
                                                            pred_at_fault(env, var_name))
 
-                if isinstance(insn, ir.Closure):
-                    env = insn.environment()
-                    # Make sure this environment has any interesting variables.
-                    if env in block_state:
-                        for var_name in block_state[env]:
-                            if not block_state[env][var_name]:
-                                # A closure would capture this variable while it is not always
-                                # initialized. Note that this check is transitive.
-                                self._uninitialized_access(insn, var_name,
-                                                           pred_at_fault(env, var_name))
+                # Creating a closure has no side effects. However, using a closure does.
+                for operand in insn.operands:
+                    if isinstance(operand, ir.Closure):
+                        env = operand.environment()
+                        # Make sure this environment has any interesting variables.
+                        if env in block_state:
+                            for var_name in block_state[env]:
+                                if not block_state[env][var_name]:
+                                    # A closure would capture this variable while it is not always
+                                    # initialized. Note that this check is transitive.
+                                    self._uninitialized_access(operand, var_name,
+                                                               pred_at_fault(env, var_name))
 
             # Save the state.
             state[block] = block_state
diff --git a/lit-test/compiler/local_access/invalid.py b/lit-test/compiler/local_access/invalid.py
index 789285d51..c67272eef 100644
--- a/lit-test/compiler/local_access/invalid.py
+++ b/lit-test/compiler/local_access/invalid.py
@@ -20,7 +20,7 @@ else:
 -t
 
 # CHECK-L: ${LINE:+1}: error: variable 't' can be captured in a closure uninitialized
-lambda: t
+l = lambda: t
 
 # CHECK-L: ${LINE:+1}: error: variable 't' can be captured in a closure uninitialized
 def f():