From bc14f4d13d3cf1d43ae809d641e29174662cd1e4 Mon Sep 17 00:00:00 2001 From: Denys Vlasenko Date: Sun, 3 Apr 2016 16:06:42 +0200 Subject: [PATCH] main(): add a TODO about finding a use for _end[] area Signed-off-by: Denys Vlasenko --- libbb/appletlib.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/libbb/appletlib.c b/libbb/appletlib.c index 4b5b09f45..d798a2eac 100644 --- a/libbb/appletlib.c +++ b/libbb/appletlib.c @@ -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