Move most of the code from the constructor of the objects statically initialized in main() into Start()/Init() functions to avoid Static Initialization Order Fiasco (https://en.cppreference.com/w/cpp/language/siof). See https://github.com/JF002/InfiniTime/pull/415#issuecomment-859004238.

src/drivers/SpiMaster.cpp

@@ -7,11 +7,14 @@
 using namespace Pinetime::Drivers;
 
 SpiMaster::SpiMaster(const SpiMaster::SpiModule spi, const SpiMaster::Parameters& params) : spi {spi}, params {params} {
-  mutex = xSemaphoreCreateBinary();
-  ASSERT(mutex != NULL);
 }
 
 bool SpiMaster::Init() {
+  if(mutex == nullptr) {
+    mutex = xSemaphoreCreateBinary();
+    ASSERT(mutex != nullptr);
+  }
+
   /* Configure GPIO pins used for pselsck, pselmosi, pselmiso and pselss for SPI0 */
   nrf_gpio_pin_set(params.pinSCK);
   nrf_gpio_cfg_output(params.pinSCK);

src/drivers/SpiMaster.h

@@ -59,7 +59,7 @@ namespace Pinetime {
       volatile uint32_t currentBufferAddr = 0;
       volatile size_t currentBufferSize = 0;
       volatile TaskHandle_t taskToNotify;
-      SemaphoreHandle_t mutex;
+      SemaphoreHandle_t mutex = nullptr;
     };
   }
 }

src/drivers/TwiMaster.cpp

@@ -9,10 +9,12 @@ using namespace Pinetime::Drivers;
 // TODO use DMA/IRQ
 
 TwiMaster::TwiMaster(const Modules module, const Parameters& params) : module {module}, params {params} {
-  mutex = xSemaphoreCreateBinary();
 }
 
 void TwiMaster::Init() {
+  if(mutex == nullptr)
+    mutex = xSemaphoreCreateBinary();
+  
   NRF_GPIO->PIN_CNF[params.pinScl] =
     ((uint32_t) GPIO_PIN_CNF_DIR_Input << GPIO_PIN_CNF_DIR_Pos) | ((uint32_t) GPIO_PIN_CNF_INPUT_Connect << GPIO_PIN_CNF_INPUT_Pos) |
     ((uint32_t) GPIO_PIN_CNF_PULL_Pullup << GPIO_PIN_CNF_PULL_Pos) | ((uint32_t) GPIO_PIN_CNF_DRIVE_S0D1 << GPIO_PIN_CNF_DRIVE_Pos) |

src/drivers/TwiMaster.h

@@ -31,7 +31,7 @@ namespace Pinetime {
       ErrorCodes Write(uint8_t deviceAddress, const uint8_t* data, size_t size, bool stop);
       void FixHwFreezed();
       NRF_TWIM_Type* twiBaseAddress;
-      SemaphoreHandle_t mutex;
+      SemaphoreHandle_t mutex = nullptr;
       const Modules module;
       const Parameters params;
       static constexpr uint8_t maxDataSize {16};