Upgrade to use C++20 (#9135)

Co-authored-by: J. Nick Koston <nick@koston.org>

esphome/components/ac_dimmer/ac_dimmer.cpp

@@ -4,6 +4,7 @@
 #include "esphome/core/helpers.h"
 #include "esphome/core/log.h"
 #include <cmath>
+#include <numbers>
 
 #ifdef USE_ESP8266
 #include <core_esp8266_waveform.h>
@@ -203,7 +204,7 @@ void AcDimmer::setup() {
 #endif
 }
 void AcDimmer::write_state(float state) {
-  state = std::acos(1 - (2 * state)) / 3.14159;  // RMS power compensation
+  state = std::acos(1 - (2 * state)) / std::numbers::pi;  // RMS power compensation
   auto new_value = static_cast<uint16_t>(roundf(state * 65535));
   if (new_value != 0 && this->store_.value == 0)
     this->store_.init_cycle = this->init_with_half_cycle_;

esphome/components/atm90e32/atm90e32.cpp

@@ -1,6 +1,7 @@
 #include "atm90e32.h"
 #include <cinttypes>
 #include <cmath>
+#include <numbers>
 #include "esphome/core/log.h"
 
 namespace esphome {
@@ -848,7 +849,7 @@ uint16_t ATM90E32Component::calculate_voltage_threshold(int line_freq, uint16_t
   float nominal_voltage = (line_freq == 60) ? 120.0f : 220.0f;
   float target_voltage = nominal_voltage * multiplier;
 
-  float peak_01v = target_voltage * 100.0f * std::sqrt(2.0f);  // convert RMS → peak, scale to 0.01V
+  float peak_01v = target_voltage * 100.0f * std::numbers::sqrt2_v<float>;  // convert RMS → peak, scale to 0.01V
   float divider = (2.0f * ugain) / 32768.0f;
 
   float threshold = peak_01v / divider;

esphome/components/display/display.cpp

@@ -1,5 +1,6 @@
 #include "display.h"
 #include <utility>
+#include <numbers>
 #include "display_color_utils.h"
 #include "esphome/core/hal.h"
 #include "esphome/core/log.h"
@@ -424,15 +425,15 @@ void HOT Display::get_regular_polygon_vertex(int vertex_id, int *vertex_x, int *
     // hence we rotate the shape by 270° to orient the polygon up.
     rotation_degrees += ROTATION_270_DEGREES;
     // Convert the rotation to radians, easier to use in trigonometrical calculations
-    float rotation_radians = rotation_degrees * PI / 180;
+    float rotation_radians = rotation_degrees * std::numbers::pi / 180;
     // A pointy top variation means the first vertex of the polygon is at the top center of the shape, this requires no
     // additional rotation of the shape.
     // A flat top variation means the first point of the polygon has to be rotated so that the first edge is horizontal,
     // this requires to rotate the shape by π/edges radians counter-clockwise so that the first point is located on the
     // left side of the first horizontal edge.
-    rotation_radians -= (variation == VARIATION_FLAT_TOP) ? PI / edges : 0.0;
+    rotation_radians -= (variation == VARIATION_FLAT_TOP) ? std::numbers::pi / edges : 0.0;
 
-    float vertex_angle = ((float) vertex_id) / edges * 2 * PI + rotation_radians;
+    float vertex_angle = ((float) vertex_id) / edges * 2 * std::numbers::pi + rotation_radians;
     *vertex_x = (int) round(cos(vertex_angle) * radius) + center_x;
     *vertex_y = (int) round(sin(vertex_angle) * radius) + center_y;
   }

esphome/components/display/display.h

@@ -138,8 +138,6 @@ enum DisplayRotation {
   DISPLAY_ROTATION_270_DEGREES = 270,
 };
 
-#define PI 3.1415926535897932384626433832795
-
 const int EDGES_TRIGON = 3;
 const int EDGES_TRIANGLE = 3;
 const int EDGES_TETRAGON = 4;

esphome/components/esp32/__init__.py

@@ -704,7 +704,7 @@ FINAL_VALIDATE_SCHEMA = cv.Schema(final_validate)
 async def to_code(config):
     cg.add_platformio_option("board", config[CONF_BOARD])
     cg.add_platformio_option("board_upload.flash_size", config[CONF_FLASH_SIZE])
-    cg.set_cpp_standard("gnu++17")
+    cg.set_cpp_standard("gnu++20")
     cg.add_build_flag("-DUSE_ESP32")
     cg.add_define("ESPHOME_BOARD", config[CONF_BOARD])
     cg.add_build_flag(f"-DUSE_ESP32_VARIANT_{config[CONF_VARIANT]}")

esphome/components/esp8266/__init__.py

@@ -183,7 +183,7 @@ async def to_code(config):
 
     cg.add_platformio_option("board", config[CONF_BOARD])
     cg.add_build_flag("-DUSE_ESP8266")
-    cg.set_cpp_standard("gnu++17")
+    cg.set_cpp_standard("gnu++20")
     cg.add_define("ESPHOME_BOARD", config[CONF_BOARD])
     cg.add_define("ESPHOME_VARIANT", "ESP8266")
 

esphome/components/esp8266/gpio.cpp

@@ -129,9 +129,9 @@ void IRAM_ATTR ISRInternalGPIOPin::digital_write(bool value) {
     }
   } else {
     if (value != arg->inverted) {
-      *arg->out_set_reg |= 1;
+      *arg->out_set_reg = *arg->out_set_reg | 1;
     } else {
-      *arg->out_set_reg &= ~1;
+      *arg->out_set_reg = *arg->out_set_reg & ~1;
     }
   }
 }
@@ -147,7 +147,7 @@ void IRAM_ATTR ISRInternalGPIOPin::pin_mode(gpio::Flags flags) {
     if (flags & gpio::FLAG_OUTPUT) {
       *arg->mode_set_reg = arg->mask;
       if (flags & gpio::FLAG_OPEN_DRAIN) {
-        *arg->control_reg |= 1 << GPCD;
+        *arg->control_reg = *arg->control_reg | (1 << GPCD);
       } else {
         *arg->control_reg &= ~(1 << GPCD);
       }
@@ -155,21 +155,21 @@ void IRAM_ATTR ISRInternalGPIOPin::pin_mode(gpio::Flags flags) {
       *arg->mode_clr_reg = arg->mask;
     }
     if (flags & gpio::FLAG_PULLUP) {
-      *arg->func_reg |= 1 << GPFPU;
-      *arg->control_reg |= 1 << GPCD;
+      *arg->func_reg = *arg->func_reg | (1 << GPFPU);
+      *arg->control_reg = *arg->control_reg | (1 << GPCD);
     } else {
-      *arg->func_reg &= ~(1 << GPFPU);
+      *arg->func_reg = *arg->func_reg & ~(1 << GPFPU);
     }
   } else {
     if (flags & gpio::FLAG_OUTPUT) {
-      *arg->mode_set_reg |= 1;
+      *arg->mode_set_reg = *arg->mode_set_reg | 1;
     } else {
-      *arg->mode_set_reg &= ~1;
+      *arg->mode_set_reg = *arg->mode_set_reg & ~1;
     }
     if (flags & gpio::FLAG_PULLDOWN) {
-      *arg->func_reg |= 1 << GP16FPD;
+      *arg->func_reg = *arg->func_reg | (1 << GP16FPD);
     } else {
-      *arg->func_reg &= ~(1 << GP16FPD);
+      *arg->func_reg = *arg->func_reg & ~(1 << GP16FPD);
     }
   }
 }

esphome/components/host/__init__.py

@@ -41,6 +41,6 @@ CONFIG_SCHEMA = cv.All(
 async def to_code(config):
     cg.add_build_flag("-DUSE_HOST")
     cg.add_define("USE_ESPHOME_HOST_MAC_ADDRESS", config[CONF_MAC_ADDRESS].parts)
-    cg.add_build_flag("-std=gnu++17")
+    cg.add_build_flag("-std=gnu++20")
     cg.add_define("ESPHOME_BOARD", "host")
     cg.add_platformio_option("platform", "platformio/native")

esphome/components/http_request/ota/ota_http_request.cpp

@@ -258,7 +258,7 @@ bool OtaHttpRequestComponent::http_get_md5_() {
 }
 
 bool OtaHttpRequestComponent::validate_url_(const std::string &url) {
-  if ((url.length() < 8) || (url.find("http") != 0) || (url.find("://") == std::string::npos)) {
+  if ((url.length() < 8) || !url.starts_with("http") || (url.find("://") == std::string::npos)) {
     ESP_LOGE(TAG, "URL is invalid and/or must be prefixed with 'http://' or 'https://'");
     return false;
   }

esphome/components/hydreon_rgxx/hydreon_rgxx.cpp

@@ -159,12 +159,6 @@ void HydreonRGxxComponent::schedule_reboot_() {
   });
 }
 
-bool HydreonRGxxComponent::buffer_starts_with_(const std::string &prefix) {
-  return this->buffer_starts_with_(prefix.c_str());
-}
-
-bool HydreonRGxxComponent::buffer_starts_with_(const char *prefix) { return buffer_.rfind(prefix, 0) == 0; }
-
 void HydreonRGxxComponent::process_line_() {
   ESP_LOGV(TAG, "Read from serial: %s", this->buffer_.substr(0, this->buffer_.size() - 2).c_str());
 
@@ -191,7 +185,7 @@ void HydreonRGxxComponent::process_line_() {
     ESP_LOGW(TAG, "Received EmSat!");
     this->em_sat_ = true;
   }
-  if (this->buffer_starts_with_("PwrDays")) {
+  if (buffer_.starts_with("PwrDays")) {
     if (this->boot_count_ <= 0) {
       this->boot_count_ = 1;
     } else {
@@ -220,7 +214,7 @@ void HydreonRGxxComponent::process_line_() {
     }
     return;
   }
-  if (this->buffer_starts_with_("SW")) {
+  if (buffer_.starts_with("SW")) {
     std::string::size_type majend = this->buffer_.find('.');
     std::string::size_type endversion = this->buffer_.find(' ', 3);
     if (majend == std::string::npos || endversion == std::string::npos || majend > endversion) {
@@ -282,7 +276,7 @@ void HydreonRGxxComponent::process_line_() {
     }
   } else {
     for (const auto *ignore : IGNORE_STRINGS) {
-      if (this->buffer_starts_with_(ignore)) {
+      if (buffer_.starts_with(ignore)) {
         ESP_LOGI(TAG, "Ignoring %s", this->buffer_.substr(0, this->buffer_.size() - 2).c_str());
         return;
       }

esphome/components/libretiny/__init__.py

@@ -264,7 +264,7 @@ async def component_to_code(config):
     # force using arduino framework
     cg.add_platformio_option("framework", "arduino")
     cg.add_build_flag("-DUSE_ARDUINO")
-    cg.set_cpp_standard("gnu++17")
+    cg.set_cpp_standard("gnu++20")
 
     # disable library compatibility checks
     cg.add_platformio_option("lib_ldf_mode", "off")

esphome/components/online_image/online_image.cpp

@@ -344,7 +344,7 @@ void OnlineImage::end_connection_() {
 }
 
 bool OnlineImage::validate_url_(const std::string &url) {
-  if ((url.length() < 8) || (url.find("http") != 0) || (url.find("://") == std::string::npos)) {
+  if ((url.length() < 8) || !url.starts_with("http") || (url.find("://") == std::string::npos)) {
     ESP_LOGE(TAG, "URL is invalid and/or must be prefixed with 'http://' or 'https://'");
     return false;
   }

esphome/components/pulse_meter/pulse_meter_sensor.cpp

@@ -63,7 +63,7 @@ void PulseMeterSensor::loop() {
   // If an edge was peeked, repay the debt
   if (this->peeked_edge_ && this->get_->count_ > 0) {
     this->peeked_edge_ = false;
-    this->get_->count_--;
+    this->get_->count_--;  // NOLINT(clang-diagnostic-deprecated-volatile)
   }
 
   // If there is an unprocessed edge, and filter_us_ has passed since, count this edge early
@@ -71,7 +71,7 @@ void PulseMeterSensor::loop() {
       now - this->get_->last_rising_edge_us_ >= this->filter_us_) {
     this->peeked_edge_ = true;
     this->get_->last_detected_edge_us_ = this->get_->last_rising_edge_us_;
-    this->get_->count_++;
+    this->get_->count_++;  // NOLINT(clang-diagnostic-deprecated-volatile)
   }
 
   // Check if we detected a pulse this loop
@@ -146,7 +146,7 @@ void IRAM_ATTR PulseMeterSensor::edge_intr(PulseMeterSensor *sensor) {
     state.last_sent_edge_us_ = now;
     set.last_detected_edge_us_ = now;
     set.last_rising_edge_us_ = now;
-    set.count_++;
+    set.count_++;  // NOLINT(clang-diagnostic-deprecated-volatile)
   }
 
   // This ISR is bound to rising edges, so the pin is high
@@ -169,7 +169,7 @@ void IRAM_ATTR PulseMeterSensor::pulse_intr(PulseMeterSensor *sensor) {
   } else if (length && !state.latched_ && sensor->last_pin_val_) {  // Long enough high edge
     state.latched_ = true;
     set.last_detected_edge_us_ = state.last_intr_;
-    set.count_++;
+    set.count_++;  // NOLINT(clang-diagnostic-deprecated-volatile)
   }
 
   // Due to order of operations this includes

esphome/components/radon_eye_ble/radon_eye_listener.cpp

@@ -17,7 +17,7 @@ bool RadonEyeListener::parse_device(const esp32_ble_tracker::ESPBTDevice &device
 
     // Check if the device name starts with any of the prefixes
     if (std::any_of(prefixes.begin(), prefixes.end(),
-                    [&](const std::string &prefix) { return device.get_name().rfind(prefix, 0) == 0; })) {
+                    [&](const std::string &prefix) { return device.get_name().starts_with(prefix); })) {
       // Device found
       ESP_LOGD(TAG, "Found Radon Eye device Name: %s (MAC: %s)", device.get_name().c_str(),
                device.address_str().c_str());

esphome/components/remote_receiver/remote_receiver_esp8266.cpp

@@ -27,7 +27,7 @@ void IRAM_ATTR HOT RemoteReceiverComponentStore::gpio_intr(RemoteReceiverCompone
   if (time_since_change <= arg->filter_us)
     return;
 
-  arg->buffer[arg->buffer_write_at = next] = now;
+  arg->buffer[arg->buffer_write_at = next] = now;  // NOLINT(clang-diagnostic-deprecated-volatile)
 }
 
 void RemoteReceiverComponent::setup() {

esphome/components/rp2040/__init__.py

@@ -167,7 +167,7 @@ async def to_code(config):
     cg.add_platformio_option("lib_ldf_mode", "chain+")
     cg.add_platformio_option("board", config[CONF_BOARD])
     cg.add_build_flag("-DUSE_RP2040")
-    cg.set_cpp_standard("gnu++17")
+    cg.set_cpp_standard("gnu++20")
     cg.add_define("ESPHOME_BOARD", config[CONF_BOARD])
     cg.add_define("ESPHOME_VARIANT", "RP2040")
 

esphome/components/sn74hc595/sn74hc595.cpp

@@ -1,5 +1,6 @@
 #include "sn74hc595.h"
 #include "esphome/core/log.h"
+#include <ranges>
 
 namespace esphome {
 namespace sn74hc595 {
@@ -55,9 +56,9 @@ void SN74HC595Component::digital_write_(uint16_t pin, bool value) {
 }
 
 void SN74HC595GPIOComponent::write_gpio() {
-  for (auto byte = this->output_bytes_.rbegin(); byte != this->output_bytes_.rend(); byte++) {
+  for (uint8_t &output_byte : std::ranges::reverse_view(this->output_bytes_)) {
     for (int8_t i = 7; i >= 0; i--) {
-      bool bit = (*byte >> i) & 1;
+      bool bit = (output_byte >> i) & 1;
       this->data_pin_->digital_write(bit);
       this->clock_pin_->digital_write(true);
       this->clock_pin_->digital_write(false);
@@ -68,9 +69,9 @@ void SN74HC595GPIOComponent::write_gpio() {
 
 #ifdef USE_SPI
 void SN74HC595SPIComponent::write_gpio() {
-  for (auto byte = this->output_bytes_.rbegin(); byte != this->output_bytes_.rend(); byte++) {
+  for (uint8_t &output_byte : std::ranges::reverse_view(this->output_bytes_)) {
     this->enable();
-    this->transfer_byte(*byte);
+    this->transfer_byte(output_byte);
     this->disable();
   }
   SN74HC595Component::write_gpio();

esphome/components/sun/sun.cpp

@@ -1,5 +1,6 @@
 #include "sun.h"
 #include "esphome/core/log.h"
+#include <numbers>
 
 /*
 The formulas/algorithms in this module are based on the book
@@ -18,14 +19,12 @@ using namespace esphome::sun::internal;
 
 static const char *const TAG = "sun";
 
-#undef PI
 #undef degrees
 #undef radians
 #undef sq
 
-static const num_t PI = 3.141592653589793;
-inline num_t degrees(num_t rad) { return rad * 180 / PI; }
-inline num_t radians(num_t deg) { return deg * PI / 180; }
+inline num_t degrees(num_t rad) { return rad * 180 / std::numbers::pi; }
+inline num_t radians(num_t deg) { return deg * std::numbers::pi / 180; }
 inline num_t arcdeg(num_t deg, num_t minutes, num_t seconds) { return deg + minutes / 60 + seconds / 3600; }
 inline num_t sq(num_t x) { return x * x; }
 inline num_t cb(num_t x) { return x * x * x; }

esphome/components/tx20/tx20.cpp

@@ -152,7 +152,7 @@ void IRAM_ATTR Tx20ComponentStore::gpio_intr(Tx20ComponentStore *arg) {
     }
     arg->buffer[arg->buffer_index] = 1;
     arg->start_time = now;
-    arg->buffer_index++;
+    arg->buffer_index++;  // NOLINT(clang-diagnostic-deprecated-volatile)
     return;
   }
   const uint32_t delay = now - arg->start_time;
@@ -183,7 +183,7 @@ void IRAM_ATTR Tx20ComponentStore::gpio_intr(Tx20ComponentStore *arg) {
   }
   arg->spent_time += delay;
   arg->start_time = now;
-  arg->buffer_index++;
+  arg->buffer_index++;  // NOLINT(clang-diagnostic-deprecated-volatile)
 }
 void IRAM_ATTR Tx20ComponentStore::reset() {
   tx20_available = false;

esphome/components/wiegand/wiegand.cpp

@@ -11,7 +11,7 @@ static const char *const KEYS = "0123456789*#";
 void IRAM_ATTR HOT WiegandStore::d0_gpio_intr(WiegandStore *arg) {
   if (arg->d0.digital_read())
     return;
-  arg->count++;
+  arg->count++;  // NOLINT(clang-diagnostic-deprecated-volatile)
   arg->value <<= 1;
   arg->last_bit_time = millis();
   arg->done = false;
@@ -20,7 +20,7 @@ void IRAM_ATTR HOT WiegandStore::d0_gpio_intr(WiegandStore *arg) {
 void IRAM_ATTR HOT WiegandStore::d1_gpio_intr(WiegandStore *arg) {
   if (arg->d1.digital_read())
     return;
-  arg->count++;
+  arg->count++;  // NOLINT(clang-diagnostic-deprecated-volatile)
   arg->value = (arg->value << 1) | 1;
   arg->last_bit_time = millis();
   arg->done = false;

esphome/core/application.cpp

@@ -3,6 +3,7 @@
 #include "esphome/core/version.h"
 #include "esphome/core/hal.h"
 #include <algorithm>
+#include <ranges>
 
 #ifdef USE_STATUS_LED
 #include "esphome/components/status_led/status_led.h"
@@ -184,8 +185,8 @@ void IRAM_ATTR HOT Application::feed_wdt(uint32_t time) {
 }
 void Application::reboot() {
   ESP_LOGI(TAG, "Forcing a reboot");
-  for (auto it = this->components_.rbegin(); it != this->components_.rend(); ++it) {
-    (*it)->on_shutdown();
+  for (auto &component : std::ranges::reverse_view(this->components_)) {
+    component->on_shutdown();
   }
   arch_restart();
 }
@@ -198,17 +199,17 @@ void Application::safe_reboot() {
 }
 
 void Application::run_safe_shutdown_hooks() {
-  for (auto it = this->components_.rbegin(); it != this->components_.rend(); ++it) {
-    (*it)->on_safe_shutdown();
+  for (auto &component : std::ranges::reverse_view(this->components_)) {
+    component->on_safe_shutdown();
   }
-  for (auto it = this->components_.rbegin(); it != this->components_.rend(); ++it) {
-    (*it)->on_shutdown();
+  for (auto &component : std::ranges::reverse_view(this->components_)) {
+    component->on_shutdown();
   }
 }
 
 void Application::run_powerdown_hooks() {
-  for (auto it = this->components_.rbegin(); it != this->components_.rend(); ++it) {
-    (*it)->on_powerdown();
+  for (auto &component : std::ranges::reverse_view(this->components_)) {
+    component->on_powerdown();
   }
 }
 

esphome/cpp_generator.py

@@ -617,7 +617,7 @@ def set_cpp_standard(standard: str) -> None:
     """Set C++ standard with compiler flag `-std={standard}`."""
     CORE.add_build_unflag("-std=gnu++11")
     CORE.add_build_unflag("-std=gnu++14")
-    CORE.add_build_unflag("-std=gnu++20")
+    CORE.add_build_unflag("-std=gnu++17")
     CORE.add_build_unflag("-std=gnu++23")
     CORE.add_build_unflag("-std=gnu++2a")
     CORE.add_build_unflag("-std=gnu++2b")

platformio.ini

@@ -47,11 +47,11 @@ lib_deps =
     lvgl/lvgl@8.4.0                                       ; lvgl
 build_flags =
     -DESPHOME_LOG_LEVEL=ESPHOME_LOG_LEVEL_VERY_VERBOSE
-    -std=gnu++17
+    -std=gnu++20
 build_unflags =
     -std=gnu++11
     -std=gnu++14
-    -std=gnu++20
+    -std=gnu++17
     -std=gnu++23
     -std=gnu++2a
     -std=gnu++2b
@@ -560,7 +560,7 @@ lib_deps =
 build_flags =
     ${common.build_flags}
     -DUSE_HOST
-    -std=c++17
+    -std=c++20
 build_unflags =
     ${common.build_unflags}