diff --git a/devito/ir/iet/scheduler.py b/devito/ir/iet/scheduler.py
index 51b72a4c83..ae8db93775 100644
--- a/devito/ir/iet/scheduler.py
+++ b/devito/ir/iet/scheduler.py
@@ -7,7 +7,7 @@
                            ExpressionBundle, Transformer, FindNodes, FindSymbols,
                            MapExprStmts, XSubs, iet_analyze)
 from devito.symbolics import IntDiv, ccode, xreplace_indices
-from devito.tools import as_mapper, as_tuple
+from devito.tools import as_mapper, as_tuple, flatten
 from devito.types import ConditionalDimension
 
 __all__ = ['iet_build', 'iet_insert_decls', 'iet_insert_casts']
@@ -168,7 +168,7 @@ def iet_insert_decls(iet, external):
                         continue
                     elif i._mem_stack:
                         # On the stack
-                        allocator.push_object_on_stack(iet[0], i)
+                        allocator.push_array_on_stack(iet[0], i)
                     else:
                         # On the heap
                         allocator.push_array_on_heap(i)
@@ -199,16 +199,21 @@ def __init__(self):
         self.stack = OrderedDict()
 
     def push_object_on_stack(self, scope, obj):
-        """Define an Array or a composite type (e.g., a struct) on the stack."""
+        """Define a LocalObject on the stack."""
         handle = self.stack.setdefault(scope, OrderedDict())
+        handle[obj] = Element(c.Value(obj._C_typename, obj.name))
 
-        if obj.is_LocalObject:
-            handle[obj] = Element(c.Value(obj._C_typename, obj.name))
-        else:
-            shape = "".join("[%s]" % ccode(i) for i in obj.symbolic_shape)
-            alignment = "__attribute__((aligned(%d)))" % obj._data_alignment
-            value = "%s%s %s" % (obj.name, shape, alignment)
-            handle[obj] = Element(c.POD(obj.dtype, value))
+    def push_array_on_stack(self, scope, obj):
+        """Define an Array on the stack."""
+        handle = self.stack.setdefault(scope, OrderedDict())
+
+        if obj in flatten(self.stack.values()):
+            return
+
+        shape = "".join("[%s]" % ccode(i) for i in obj.symbolic_shape)
+        alignment = "__attribute__((aligned(%d)))" % obj._data_alignment
+        value = "%s%s %s" % (obj.name, shape, alignment)
+        handle[obj] = Element(c.POD(obj.dtype, value))
 
     def push_scalar_on_stack(self, scope, expr):
         """Define a Scalar on the stack."""
diff --git a/tests/test_operator.py b/tests/test_operator.py
index 789173d53b..682c4ddd5c 100644
--- a/tests/test_operator.py
+++ b/tests/test_operator.py
@@ -6,10 +6,12 @@
                     SparseFunction, SparseTimeFunction, Dimension, error, SpaceDimension,
                     NODE, CELL, dimensions, configuration, TensorFunction,
                     TensorTimeFunction, VectorFunction, VectorTimeFunction)
-from devito.ir.iet import (Expression, Iteration, FindNodes, IsPerfectIteration,
+from devito.ir.equations import ClusterizedEq
+from devito.ir.iet import (Conditional, Expression, Iteration, FindNodes,
+                           IsPerfectIteration, derive_parameters, iet_insert_decls,
                            retrieve_iteration_tree)
 from devito.ir.support import Any, Backward, Forward
-from devito.symbolics import indexify, retrieve_indexed
+from devito.symbolics import ListInitializer, indexify, retrieve_indexed
 from devito.tools import flatten
 from devito.types import Array, Scalar
 
@@ -1143,6 +1145,22 @@ def test_stack_vector_temporaries(self):
   timers->section0 += (double)(end_section0.tv_sec-start_section0.tv_sec)\
 +(double)(end_section0.tv_usec-start_section0.tv_usec)/1000000;""" in str(operator)
 
+    def test_conditional_declarations(self):
+        a = Array(name='a', dimensions=(x,), dtype=np.int32, scope='stack')
+        list_initialize = Expression(ClusterizedEq(Eq(a, ListInitializer([0, 0]))))
+        iet = Conditional(x < 3, list_initialize, list_initialize)
+        parameters = derive_parameters(iet, True)
+        iet = iet_insert_decls(iet, parameters)
+        assert str(iet[0]) == """\
+if (x < 3)
+{
+  int a[x_size] = {0, 0};
+}
+else
+{
+  int a[x_size] = {0, 0};
+}"""
+
 
 class TestLoopScheduling(object):
 
diff --git a/tests/test_ops.py b/tests/test_ops.py
index 64e4d97a31..042656114c 100644
--- a/tests/test_ops.py
+++ b/tests/test_ops.py
@@ -13,13 +13,15 @@
 # thus invalidating all of the future tests. This is guaranteed by the
 # `pytestmark` above
 from devito import Eq, Function, Grid, Operator, TimeFunction, configuration  # noqa
+from devito.ir.equations import ClusterizedEq  # noqa
+from devito.ir.iet import Conditional, Expression, derive_parameters, iet_insert_decls  # noqa
 from devito.ops.node_factory import OPSNodeFactory  # noqa
 from devito.ops.transformer import create_ops_arg, create_ops_dat, make_ops_ast, to_ops_stencil  # noqa
-from devito.ops.types import OpsAccessible, OpsDat, OpsStencil, OpsBlock  # noqa
+from devito.ops.types import Array, OpsAccessible, OpsDat, OpsStencil, OpsBlock  # noqa
 from devito.ops.utils import namespace, AccessibleInfo, OpsDatDecl, OpsArgDecl  # noqa
-from devito.symbolics import Byref, Literal, indexify  # noqa
+from devito.symbolics import Byref, ListInitializer, Literal, indexify  # noqa
 from devito.tools import dtype_to_cstr  # noqa
-from devito.types import Buffer, Constant, Symbol  # noqa
+from devito.types import Buffer, Constant, DefaultDimension, Symbol  # noqa
 
 
 class TestOPSExpression(object):
@@ -272,11 +274,24 @@ def test_create_ops_block(self, equation, expected):
     ])
     def test_upper_bound(self, equation, expected):
         grid = Grid((5, 5))
-        u = TimeFunction(name='u', grid=grid) # noqa
+        u = TimeFunction(name='u', grid=grid)  # noqa
         op = Operator(eval(equation))
 
         assert expected in str(op.ccode)
 
+    @pytest.mark.parametrize('equation, declaration', [
+        ('Eq(u.forward, u+1)',
+         'int OPS_Kernel_0_range[4]')
+    ])
+    def test_single_declaration(self, equation, declaration):
+        grid = Grid((5, 5))
+        u = TimeFunction(name='u', grid=grid)  # noqa
+        op = Operator(eval(equation))
+
+        occurrences = [i for i in str(op.ccode).split('\n') if declaration in i]
+
+        assert len(occurrences) == 1
+
     @pytest.mark.parametrize('equation,expected', [
         ('Eq(u_2d.forward, u_2d + 1)',
          '[\'ops_dat_fetch_data(u_dat[(time_M)%(2)],0,&(u[(time_M)%(2)]));\','