0

I have a custom linker script for an stm32f4 chip, mostly working; the application start-up and run, global array and variable are correctly initialized BUT global object are not.

I found around some reference to ctor usage instead of __init_array but those seems to be older methodology.

In the LD I added the sections:

. = ALIGN(4);
.preinit_array     :
{
  PROVIDE_HIDDEN (__preinit_array_start = .);
  KEEP (*(.preinit_array*))
  PROVIDE_HIDDEN (__preinit_array_end = .);
} >FLASH
. = ALIGN(4);
.init_array :
{
  PROVIDE_HIDDEN (__init_array_start = .);
  KEEP (*(SORT(.init_array.*)))
  KEEP (*(.init_array*))
  PROVIDE_HIDDEN (__init_array_end = .);
} >FLASH
. = ALIGN(4);
.fini_array :
{
  PROVIDE_HIDDEN (__fini_array_start = .);
  KEEP (*(SORT(.fini_array.*)))
  KEEP (*(.fini_array*))
  PROVIDE_HIDDEN (__fini_array_end = .);
} >FLASH

and the full startup script:

extern unsigned long _data_flash;
extern unsigned long _data_begin;
extern unsigned long _data_end;
extern unsigned long _bss_begin;
extern unsigned long _bss_end;
extern void (**__preinit_array_start)();
extern void (**__preinit_array_end)();
extern void (**__init_array_start)();
extern void (**__init_array_end)();


inline void static_init()
{
  for (void (**p)() = __preinit_array_start; p < __preinit_array_end; ++p)
    (*p)();

  for (void (**p)() = __init_array_start; p < __init_array_end; ++p)
    (*p)();
}

void reset_handler(void)
{
  unsigned long *source;
  unsigned long *destination;

  // default zero to undefined variables
  for (destination = &_bss_begin; destination < &_bss_end;)
  {
    *(destination++) = 0;
  }

  // Copying data from Flash to RAM
  source = &_data_flash;
  for (destination = &_data_begin; destination < &_data_end;)
  {
    *(destination++) = *(source++);
  }


  SystemInit();

  static_init();

  // starting main program
  main();

  while(1)
  {
    ; //loop forever, but we should never be there
  }
}

Could it be the official startup script from ST are doing some black (and maybe proprietary) magic to make it work properly?

I got this same code work properly when using another compiler, so I exclude an issue in the code.

edit: after some debugging i tried:

printf("preinit %32x %32x\r\n", __preinit_array_start, __preinit_array_end);
printf("init %32x %32x\r\n", __init_array_start, __init_array_end);
printf("preinit2 %32x %32x\r\n", *__preinit_array_start, *__preinit_array_end);
printf("init2 %32x %32x\r\n", *__init_array_start, *__init_array_end);

that return:

preinit 080506E9 080506E9<\r><\n>
init 080506E9 00000000<\r><\n>
preinit2 BB4FF8E9 BB4FF8E9<\r><\n>
init2 BB4FF8E9 20000418<\r><\n>

This is quite interesting, seem "__init_array_end " somehow is not keept

4

1 回答 1

0

在发现__init_array_end__地址错误后，我尝试更深入地查看链接器脚本，并决定尝试使用 Atollic Studio 用于 C++ 的变体。（请注意前面的链接器脚本取自 st 标准外设示例）

与工作链接器脚本的区别主要.bss是没有NOLOAD属性和初始化堆的不同方式，并且.data设置为>RAM AT> FLASH而不是仅>RAM

于 2018-05-25T14:49:50.647 回答