How to increase heap size for Cortex-M4 example?

I am running the "CMSIS-RTOS2 Blinky (uVision Simulator)" example for Cortex-M4 in Arm Dev Studio on Windows. I am using ARM C/C++ Compiler 6.

The example runs ok. I have now added several C++ files to it. These compile and link ok, but when I increase the number of objects ( instantiated by new() ) on the heap the program either crashes or raises a bad_alloc exception.

I have tried increasing the heap allocation in the scatter file but that seems to make no difference. I am therefore wondering whether I am increasing it correctly or whether there is some startup requirement for C++ that I am unaware of.

My scatter file is:

CMSIS-RTOS2 Blinky (uVision Simulator)_Simulation\RTE\Device\ARMCM4\ARMCM4_ac6.sct

and the contents are:

#! armclang -E --target=arm-arm-none-eabi -mcpu=cortex-m4 -xc
; command above MUST be in first line (no comment above!)

/*
;-------- <<< Use Configuration Wizard in Context Menu >>> -------------------
*/

/*--------------------- Flash Configuration ----------------------------------
; <h> Flash Configuration
;   <o0> Flash Base Address <0x0-0xFFFFFFFF:8>
;   <o1> Flash Size (in Bytes) <0x0-0xFFFFFFFF:8>
; </h>
 *----------------------------------------------------------------------------*/
#define __ROM_BASE      0x00000000
#define __ROM_SIZE      0x00080000

/*--------------------- Embedded RAM Configuration ---------------------------
; <h> RAM Configuration
;   <o0> RAM Base Address    <0x0-0xFFFFFFFF:8>
;   <o1> RAM Size (in Bytes) <0x0-0xFFFFFFFF:8>
; </h>
 *----------------------------------------------------------------------------*/
#define __RAM_BASE      0x20000000
#define __RAM_SIZE      0x00040000

/*--------------------- Stack / Heap Configuration ---------------------------
; <h> Stack / Heap Configuration
;   <o0> Stack Size (in Bytes) <0x0-0xFFFFFFFF:8>
;   <o1> Heap Size (in Bytes) <0x0-0xFFFFFFFF:8>
; </h>
 *----------------------------------------------------------------------------*/
#define __STACK_SIZE    0x00000400
#define __HEAP_SIZE     0x0000A000

/*
;------------- <<< end of configuration section >>> ---------------------------
*/


/*----------------------------------------------------------------------------
  User Stack & Heap boundary definition
 *----------------------------------------------------------------------------*/
#define __STACK_TOP    (__RAM_BASE + __RAM_SIZE)    /* starts at end of RAM */
#define __HEAP_BASE    (AlignExpr(+0, 8))           /* starts after RW_RAM section, 8 byte aligned */


/*----------------------------------------------------------------------------
  Scatter File Definitions definition
 *----------------------------------------------------------------------------*/
#define __RO_BASE       __ROM_BASE
#define __RO_SIZE       __ROM_SIZE

#define __RW_BASE       __RAM_BASE
#define __RW_SIZE      (__RAM_SIZE - __STACK_SIZE - __HEAP_SIZE)


LR_ROM __RO_BASE __RO_SIZE  {                       ; load region size_region
  ER_ROM __RO_BASE __RO_SIZE  {                     ; load address = execution address
   *.o (RESET, +First)
   *(InRoot$$Sections)
   .ANY (+RO)
   .ANY (+XO)
  }

  RW_RAM __RW_BASE __RW_SIZE  {                     ; RW data
   .ANY (+RW +ZI)
  }

#if __HEAP_SIZE > 0
  ARM_LIB_HEAP  __HEAP_BASE EMPTY  __HEAP_SIZE  {   ; Reserve empty region for heap
  }
#endif

  ARM_LIB_STACK __STACK_TOP EMPTY -__STACK_SIZE {   ; Reserve empty region for stack
  }
}

so the heap allocation should be 0xA000.

The linker command is:

armlink.exe --entry=Reset_Handler --scatter="C:\prototypes\CMSIS-RTOS2 Blinky (uVision Simulator)_Simulation/RTE/Device/ARMCM4/ARMCM4_ac6.sct" 
--info=sizes --strict 
-o "CMSIS-RTOS2 Blinky (uVision Simulator)_Simulation.axf"  
./src/Elysion.o ./src/ElysionSectionList.o  
./RTE/Device/ARMCM4/startup_ARMCM4.o ./RTE/Device/ARMCM4/system_ARMCM4.o  
./RTE/Compiler/EventRecorder.o  ./RTE/CMSIS/RTX_Config.o ./RTE/CMSIS/irq_armv7m.o 
./RTE/CMSIS/os_systick.o ./RTE/CMSIS/rtx_delay.o ./RTE/CMSIS/rtx_evflags.o 
./RTE/CMSIS/rtx_evr.o ./RTE/CMSIS/rtx_kernel.o ./RTE/CMSIS/rtx_lib.o 
./RTE/CMSIS/rtx_memory.o ./RTE/CMSIS/rtx_mempool.o ./RTE/CMSIS/rtx_msgqueue.o 
./RTE/CMSIS/rtx_mutex.o ./RTE/CMSIS/rtx_semaphore.o ./RTE/CMSIS/rtx_system.o 
./RTE/CMSIS/rtx_thread.o ./RTE/CMSIS/rtx_timer.o  
./Blinky.o ./ElysionMain.o   

so, correct scatter code and, hopefully, correct startup files are used.

My C++ compiler options are:

armclang.exe --target=arm-arm-none-eabi 
-I"C:\prototypes\CMSIS-RTOS2 Blinky (uVision Simulator)_Simulation/src" 
-xc++ -fexceptions -O0 -g -DARMCM4 -D_RTE_ 
-mcpu=cortex-m4 -mfpu=none -mlittle-endian -Oz -g -Wall 
-fshort-enums -fshort-wchar -ffunction-sections -fno-rtti 
-MD -MP -c -o "ElysionMain.o" "../ElysionMain.cpp"

Can you please suggest what may be wrong?