trying to fix startup file

Author: Andrea Gilardoni

targets/TARGET_STM/TARGET_STM32L0/TARGET_MCU_STM32L071xx/device/TOOLCHAIN_GCC_ARM/startup_stm32l071xx.S

@@ -1,8 +1,8 @@
 /**
   ******************************************************************************
-  * @file      startup_stm32l073xx.s
+  * @file      startup_stm32l071xx.s
   * @author    MCD Application Team
-  * @brief     STM32L073xx Devices vector table for Atollic TrueSTUDIO toolchain.
+  * @brief     STM32L071xx Devices vector table for GCC toolchain.
   *            This module performs:
   *                - Set the initial SP
   *                - Set the initial PC == Reset_Handler,
@@ -12,7 +12,7 @@
   *            After Reset the Cortex-M0+ processor is in Thread mode,
   *            priority is Privileged, and the Stack is set to Main.
   ******************************************************************************
-  *
+  * 
   * Redistribution and use in source and binary forms, with or without modification,
   * are permitted provided that the following conditions are met:
   *   1. Redistributions of source code must retain the above copyright notice,
@@ -53,6 +53,10 @@ defined in linker script */
 .word  _sdata
 /* end address for the .data section. defined in linker script */
 .word  _edata
+/* start address for the .bss section. defined in linker script */
+.word  _sbss
+/* end address for the .bss section. defined in linker script */
+.word  _ebss
 
     .section  .text.Reset_Handler
   .weak  Reset_Handler
@@ -77,6 +81,19 @@ LoopCopyDataInit:
   adds  r2, r0, r1
   cmp  r2, r3
   bcc  CopyDataInit
+  ldr  r2, =_sbss
+  b  LoopFillZerobss
+/* Zero fill the bss segment. */
+FillZerobss:
+  movs  r3, #0
+  str  r3, [r2]
+  adds r2, r2, #4
+
+
+LoopFillZerobss:
+  ldr  r3, = _ebss
+  cmp  r2, r3
+  bcc  FillZerobss
 
 /* Call the clock system intitialization function.*/
   bl  SystemInit
@@ -138,11 +155,11 @@ g_pfnVectors:
   .word     PVD_IRQHandler                    /* PVD through EXTI Line detection */
   .word     RTC_IRQHandler                    /* RTC through the EXTI line     */
   .word     FLASH_IRQHandler                  /* FLASH                        */
-  .word     RCC_CRS_IRQHandler                /* RCC and CRS                  */
+  .word     RCC_IRQHandler                    /* RCC                          */
   .word     EXTI0_1_IRQHandler                /* EXTI Line 0 and 1            */
   .word     EXTI2_3_IRQHandler                /* EXTI Line 2 and 3            */
   .word     EXTI4_15_IRQHandler               /* EXTI Line 4 to 15            */
-  .word     TSC_IRQHandler                     /* TSC                           */
+  .word     0                                 /* Reserved                     */
   .word     DMA1_Channel1_IRQHandler          /* DMA1 Channel 1               */
   .word     DMA1_Channel2_3_IRQHandler        /* DMA1 Channel 2 and Channel 3 */
   .word     DMA1_Channel4_5_6_7_IRQHandler    /* DMA1 Channel 4, Channel 5, Channel 6 and Channel 7*/
@@ -151,7 +168,7 @@ g_pfnVectors:
   .word     USART4_5_IRQHandler               /* USART4 and USART 5           */
   .word     TIM2_IRQHandler                   /* TIM2                         */
   .word     TIM3_IRQHandler                   /* TIM3                         */
-  .word     TIM6_DAC_IRQHandler               /* TIM6 and DAC                 */
+  .word     TIM6_IRQHandler                   /* TIM6 and DAC                 */
   .word     TIM7_IRQHandler 				          /* TIM7                         */
   .word     0              					          /* Reserved                     */
   .word     TIM21_IRQHandler                  /* TIM21                        */
@@ -163,9 +180,9 @@ g_pfnVectors:
   .word     SPI2_IRQHandler                   /* SPI2                         */
   .word     USART1_IRQHandler                 /* USART1                       */
   .word     USART2_IRQHandler                 /* USART2                       */
-  .word     RNG_LPUART1_IRQHandler            /* RNG and LPUART1              */
-  .word     LCD_IRQHandler                    /* LCD                          */
-  .word     USB_IRQHandler                    /* USB                          */
+  .word     LPUART1_IRQHandler                /* LPUART1                      */
+  .word     0                                 /* Reserved                     */
+  .word     0                                 /* Reserved                     */
 
 /*******************************************************************************
 *
@@ -202,8 +219,8 @@ g_pfnVectors:
    .weak      FLASH_IRQHandler
    .thumb_set FLASH_IRQHandler,Default_Handler
 
-   .weak      RCC_CRS_IRQHandler
-   .thumb_set RCC_CRS_IRQHandler,Default_Handler
+   .weak      RCC_IRQHandler
+   .thumb_set RCC_IRQHandler,Default_Handler
 
    .weak      EXTI0_1_IRQHandler
    .thumb_set EXTI0_1_IRQHandler,Default_Handler
@@ -214,9 +231,6 @@ g_pfnVectors:
    .weak      EXTI4_15_IRQHandler
    .thumb_set EXTI4_15_IRQHandler,Default_Handler
 
-   .weak      TSC_IRQHandler
-   .thumb_set TSC_IRQHandler,Default_Handler
-
    .weak      DMA1_Channel1_IRQHandler
    .thumb_set DMA1_Channel1_IRQHandler,Default_Handler
 
@@ -241,8 +255,8 @@ g_pfnVectors:
    .weak      TIM3_IRQHandler
    .thumb_set TIM3_IRQHandler,Default_Handler
 
-   .weak      TIM6_DAC_IRQHandler
-   .thumb_set TIM6_DAC_IRQHandler,Default_Handler
+   .weak      TIM6_IRQHandler
+   .thumb_set TIM6_IRQHandler,Default_Handler
 
    .weak      TIM7_IRQHandler
    .thumb_set TIM7_IRQHandler,Default_Handler
@@ -274,14 +288,8 @@ g_pfnVectors:
    .weak      USART2_IRQHandler
    .thumb_set USART2_IRQHandler,Default_Handler
 
-   .weak      RNG_LPUART1_IRQHandler
-   .thumb_set RNG_LPUART1_IRQHandler,Default_Handler
-
-   .weak      LCD_IRQHandler
-   .thumb_set LCD_IRQHandler,Default_Handler
-
-   .weak      USB_IRQHandler
-   .thumb_set USB_IRQHandler,Default_Handler
+   .weak      LPUART1_IRQHandler
+   .thumb_set LPUART1_IRQHandler,Default_Handler