main(): add a TODO about finding a use for _end[] area

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
This commit is contained in:
Denys Vlasenko 2016-04-03 16:06:42 +02:00
parent 056e1f558c
commit bc14f4d13d

View File

@ -902,6 +902,19 @@ int lbb_main(char **argv)
int main(int argc UNUSED_PARAM, char **argv)
#endif
{
#if 0
/* TODO: find a use for a block of memory between end of .bss
* and end of page. For example, I'm getting "_end:0x812e698 2408 bytes"
* - more than 2k of wasted memory (in this particular build)
* *per each running process*!
* (If your linker does not generate "_end" name, weak attribute
* makes &_end == NULL, end_len == 0 here.)
*/
extern char _end[] __attribute__((weak));
unsigned end_len = (-(int)_end) & 0xfff;
printf("_end:%p %u bytes\n", &_end, end_len);
#endif
/* Tweak malloc for reduced memory consumption */
#ifdef M_TRIM_THRESHOLD
/* M_TRIM_THRESHOLD is the maximum amount of freed top-most memory