avoid template overhead

esphome/core/helpers.h

@@ -2222,27 +2222,6 @@ template<std::totally_ordered T, comparable_with<T> U> T clamp_at_most(T value,
   return value;
 }
 
-/**
- * @brief Provides properly aligned, uninitialized static storage for a given type T.
- *
- * This struct is designed to replace dynamic heap allocations (`new T(...)`) for
- * global or static singletons within ESPHome, preventing memory fragmentation.
- * The underlying object must be explicitly constructed using placement new
- * before access. No destructor is called — this is intentional since ESPHome
- * singletons live for the entire device lifetime.
- */
-template<class T> struct PlacementStorage {
-  /// @brief Raw byte storage, strictly aligned for type T.
-  alignas(T) unsigned char data[sizeof(T)];
-
-  /// @brief Retrieves a pointer to the storage as the target type.
-  /// The caller must ensure the object has been constructed via placement new before dereferencing.
-  T *get() { return reinterpret_cast<T *>(data); }
-
-  /// @brief Retrieves a const pointer to the storage as the target type.
-  const T *get() const { return reinterpret_cast<const T *>(data); }
-};
-
 /// @name Internal functions
 ///@{
 

esphome/cpp_generator.py

@@ -584,18 +584,20 @@ def Pvariable(id_: ID, rhs: SafeExpType, type_: "MockObj" = None) -> "MockObj":
         # For 'new' allocations, use placement new into static storage
         # to avoid heap fragmentation on embedded devices.
         the_type = id_.type
-        storage_type = MockObj(f"esphome::PlacementStorage<{the_type}>")
+        storage_name = f"{id_.id}_storage_"
-        storage_id = ID(f"{id_.id}_storage_", type=storage_type)
 
+        # Declare aligned byte array for the object storage
         CORE.add_global(
-            VariableDeclarationExpression(storage_type, "", storage_id, static=True)
+            RawStatement(
+                f"alignas({the_type}) static unsigned char {storage_name}[sizeof({the_type})];"
+            )
         )
         CORE.add_global(
             AssignmentExpression(
                 f"static {the_type}",
                 "*const ",
                 id_,
-                MockObj(f"{storage_id.id}.get()"),
+                MockObj(f"reinterpret_cast<{the_type} *>({storage_name})"),
             )
         )
         # Extract args from the CallExpression and rebuild as placement new.

tests/component_tests/deep_sleep/test_deep_sleep.py

@@ -8,7 +8,7 @@ def test_deep_sleep_setup(generate_main):
     main_cpp = generate_main("tests/component_tests/deep_sleep/test_deep_sleep1.yaml")
 
     assert (
-        "static deep_sleep::DeepSleepComponent *const deepsleep = deepsleep_storage_.get();"
+        "static deep_sleep::DeepSleepComponent *const deepsleep = reinterpret_cast<deep_sleep::DeepSleepComponent *>(deepsleep_storage_);"
         in main_cpp
     )
     assert "new(deepsleep) deep_sleep::DeepSleepComponent();" in main_cpp

tests/component_tests/globals/test_globals.py

@@ -16,12 +16,12 @@ def test_globals_placement_new_with_template_args(
     # Globals uses Pvariable with Type.new(template_args, initial_value)
     # which exercises the template_args preservation in placement new.
     assert "static globals::GlobalsComponent<int> *const my_global_int" in main_cpp
-    assert "PlacementStorage<globals::GlobalsComponent<int>>" in main_cpp
+    assert "sizeof(globals::GlobalsComponent<int>)" in main_cpp
     assert "new(my_global_int) globals::GlobalsComponent<int>" in main_cpp
 
     # Verify initial value is passed as constructor arg
     assert "42" in main_cpp
 
     # Check other globals are also generated
-    assert "PlacementStorage<globals::GlobalsComponent<float>>" in main_cpp
+    assert "sizeof(globals::GlobalsComponent<float>)" in main_cpp
-    assert "PlacementStorage<globals::GlobalsComponent<bool>>" in main_cpp
+    assert "sizeof(globals::GlobalsComponent<bool>)" in main_cpp

tests/component_tests/image/test_init.py

@@ -242,9 +242,13 @@ def test_image_generation(
     main_cpp = generate_main(component_config_path("image_test.yaml"))
     assert "uint8_t_id[] PROGMEM = {0x24, 0x21, 0x24, 0x21" in main_cpp
     assert (
-        "static esphome::PlacementStorage<image::Image> cat_img_storage_;" in main_cpp
+        "alignas(image::Image) static unsigned char cat_img_storage_[sizeof(image::Image)];"
+        in main_cpp
+    )
+    assert (
+        "static image::Image *const cat_img = reinterpret_cast<image::Image *>(cat_img_storage_);"
+        in main_cpp
     )
-    assert "static image::Image *const cat_img = cat_img_storage_.get();" in main_cpp
     assert (
         "new(cat_img) image::Image(uint8_t_id, 32, 24, image::IMAGE_TYPE_RGB565, image::TRANSPARENCY_OPAQUE);"
         in main_cpp

tests/component_tests/mipi_dsi/test_mipi_dsi_config.py

@@ -119,11 +119,12 @@ def test_code_generation(
 
     main_cpp = generate_main(component_fixture_path("mipi_dsi.yaml"))
     assert (
-        "static esphome::PlacementStorage<mipi_dsi::MIPI_DSI> p4_nano_storage_;"
+        "alignas(mipi_dsi::MIPI_DSI) static unsigned char p4_nano_storage_[sizeof(mipi_dsi::MIPI_DSI)];"
         in main_cpp
     )
     assert (
-        "static mipi_dsi::MIPI_DSI *const p4_nano = p4_nano_storage_.get();" in main_cpp
+        "static mipi_dsi::MIPI_DSI *const p4_nano = reinterpret_cast<mipi_dsi::MIPI_DSI *>(p4_nano_storage_);"
+        in main_cpp
     )
     assert (
         "new(p4_nano) mipi_dsi::MIPI_DSI(800, 1280, display::COLOR_BITNESS_565, 16);"

tests/component_tests/status_led/test_status_led.py

@@ -13,11 +13,11 @@ def test_status_led_generation(
     """Test status_led generation."""
     main_cpp = generate_main(component_config_path("status_led_test.yaml"))
     assert (
-        "static esphome::PlacementStorage<status_led::StatusLED> status_led_statusled_id_storage_;"
+        "alignas(status_led::StatusLED) static unsigned char status_led_statusled_id_storage_[sizeof(status_led::StatusLED)];"
         in main_cpp
     )
     assert (
-        "static status_led::StatusLED *const status_led_statusled_id = status_led_statusled_id_storage_.get();"
+        "static status_led::StatusLED *const status_led_statusled_id = reinterpret_cast<status_led::StatusLED *>(status_led_statusled_id_storage_);"
         in main_cpp
     )
     assert "new(status_led_statusled_id) status_led::StatusLED(" in main_cpp