diff --git a/targets/TARGET_STM/TARGET_STM32F7/TARGET_DISCO_F746NG/device/TOOLCHAIN_GCC_ARM/startup_stm32f746xx.S b/targets/TARGET_STM/TARGET_STM32F7/TARGET_DISCO_F746NG/device/TOOLCHAIN_GCC_ARM/startup_stm32f746xx.S
index b14a8455b8..8a950e13b3 100644
--- a/targets/TARGET_STM/TARGET_STM32F7/TARGET_DISCO_F746NG/device/TOOLCHAIN_GCC_ARM/startup_stm32f746xx.S
+++ b/targets/TARGET_STM/TARGET_STM32F7/TARGET_DISCO_F746NG/device/TOOLCHAIN_GCC_ARM/startup_stm32f746xx.S
@@ -58,10 +58,6 @@ 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
 /* stack used for SystemInit_ExtMemCtl; always internal RAM used */
 
 /**
@@ -95,17 +91,6 @@ 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], #4
-    
-LoopFillZerobss:
-  ldr  r3, = _ebss
-  cmp  r2, r3
-  bcc  FillZerobss
 
 /* Call the clock system initialization function.*/
   bl  SystemInit   
diff --git a/targets/TARGET_STM/TARGET_STM32F7/TARGET_DISCO_F769NI/device/TOOLCHAIN_GCC_ARM/startup_stm32f769xx.S b/targets/TARGET_STM/TARGET_STM32F7/TARGET_DISCO_F769NI/device/TOOLCHAIN_GCC_ARM/startup_stm32f769xx.S
index 3cb97ec633..72833bf176 100644
--- a/targets/TARGET_STM/TARGET_STM32F7/TARGET_DISCO_F769NI/device/TOOLCHAIN_GCC_ARM/startup_stm32f769xx.S
+++ b/targets/TARGET_STM/TARGET_STM32F7/TARGET_DISCO_F769NI/device/TOOLCHAIN_GCC_ARM/startup_stm32f769xx.S
@@ -58,10 +58,6 @@ 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
 /* stack used for SystemInit_ExtMemCtl; always internal RAM used */
 
 /**
@@ -95,17 +91,6 @@ 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], #4
-    
-LoopFillZerobss:
-  ldr  r3, = _ebss
-  cmp  r2, r3
-  bcc  FillZerobss
 
 /* Call the clock system initialization function.*/
   bl  SystemInit   
diff --git a/targets/TARGET_STM/TARGET_STM32F7/TARGET_F746_F756/device/TOOLCHAIN_GCC_ARM/startup_stm32f746xx.S b/targets/TARGET_STM/TARGET_STM32F7/TARGET_F746_F756/device/TOOLCHAIN_GCC_ARM/startup_stm32f746xx.S
index b14a8455b8..8a950e13b3 100644
--- a/targets/TARGET_STM/TARGET_STM32F7/TARGET_F746_F756/device/TOOLCHAIN_GCC_ARM/startup_stm32f746xx.S
+++ b/targets/TARGET_STM/TARGET_STM32F7/TARGET_F746_F756/device/TOOLCHAIN_GCC_ARM/startup_stm32f746xx.S
@@ -58,10 +58,6 @@ 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
 /* stack used for SystemInit_ExtMemCtl; always internal RAM used */
 
 /**
@@ -95,17 +91,6 @@ 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], #4
-    
-LoopFillZerobss:
-  ldr  r3, = _ebss
-  cmp  r2, r3
-  bcc  FillZerobss
 
 /* Call the clock system initialization function.*/
   bl  SystemInit   
diff --git a/targets/TARGET_STM/TARGET_STM32F7/TARGET_NUCLEO_F767ZI/device/TOOLCHAIN_GCC_ARM/startup_stm32f769xx.s b/targets/TARGET_STM/TARGET_STM32F7/TARGET_NUCLEO_F767ZI/device/TOOLCHAIN_GCC_ARM/startup_stm32f769xx.s
index 3cb97ec633..72833bf176 100644
--- a/targets/TARGET_STM/TARGET_STM32F7/TARGET_NUCLEO_F767ZI/device/TOOLCHAIN_GCC_ARM/startup_stm32f769xx.s
+++ b/targets/TARGET_STM/TARGET_STM32F7/TARGET_NUCLEO_F767ZI/device/TOOLCHAIN_GCC_ARM/startup_stm32f769xx.s
@@ -58,10 +58,6 @@ 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
 /* stack used for SystemInit_ExtMemCtl; always internal RAM used */
 
 /**
@@ -95,17 +91,6 @@ 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], #4
-    
-LoopFillZerobss:
-  ldr  r3, = _ebss
-  cmp  r2, r3
-  bcc  FillZerobss
 
 /* Call the clock system initialization function.*/
   bl  SystemInit