diff --git a/devito/ir/iet/visitors.py b/devito/ir/iet/visitors.py
index 2f1987aca9..228a3e7f86 100644
--- a/devito/ir/iet/visitors.py
+++ b/devito/ir/iet/visitors.py
@@ -705,7 +705,15 @@ def visit_Operator(self, o, mode='all'):
             efuncs.extend([self._visit(i), blankline])
 
         # Definitions
-        headers = [c.Define(*i) for i in o._headers] + [blankline]
+        headers = []
+        for h in o._headers:
+            try:
+                headers.append(c.Define(*h))
+            except TypeError:
+                # Plain string
+                headers.append(c.Line(h))
+        headers = headers + [blankline]
+        # headers = [c.Define(*i) for i in o._headers] + [blankline]
 
         # Header files
         includes = self._operator_includes(o) + [blankline]
diff --git a/devito/passes/iet/dtypes.py b/devito/passes/iet/dtypes.py
index 95b944c2b1..619d81fd8a 100644
--- a/devito/passes/iet/dtypes.py
+++ b/devito/passes/iet/dtypes.py
@@ -30,7 +30,7 @@ def _complex_includes(iet: Callable, lang: type[LangBB], compiler: Compiler,
         return iet, {}
 
     metadata = {}
-    lib = as_tuple(lang['header-complex'])
+    lib = as_tuple(lang['includes-complex'])
 
     if lang.get('complex-namespace') is not None:
         metadata['namespaces'] = lang['complex-namespace']
diff --git a/devito/passes/iet/languages/C.py b/devito/passes/iet/languages/C.py
index 0453bdcad7..3bcade46e2 100644
--- a/devito/passes/iet/languages/C.py
+++ b/devito/passes/iet/languages/C.py
@@ -25,7 +25,7 @@ class CBB(LangBB):
         'alloc-global-symbol': lambda i, j, k:
             Call('memcpy', (i, j, k)),
         # Complex and float16
-        'header-complex': 'complex.h',
+        'includes-complex': 'complex.h',
     }
 
 
diff --git a/devito/passes/iet/languages/CXX.py b/devito/passes/iet/languages/CXX.py
index 5554308a0c..52e4ba695b 100644
--- a/devito/passes/iet/languages/CXX.py
+++ b/devito/passes/iet/languages/CXX.py
@@ -61,7 +61,7 @@ class CXXBB(LangBB):
         'alloc-global-symbol': lambda i, j, k:
             Call('memcpy', (i, j, k)),
         # Complex and float16
-        'header-complex': 'complex',
+        'includes-complex': 'complex',
         'complex-namespace': [UsingNamespace('std::complex_literals')],
         'def-complex': std_arith,
     }