Why this code snippet encounter segment fault when setting the min_alloc_size for the constructor for boost::pool<> whereas it works well without setting the said parameter?
Here is the code snippet:
#include <boost/pool/pool.hpp>
#include <iostream>
int main()
{
boost::pool<> pool_a(1024*128);
boost::pool<> pool_b(1024*128, 5*1024*1024);
auto get_mem_blk = [](boost::pool<>& pool)
{
char* ptr = (char*)pool.ordered_malloc();
pool.ordered_free(ptr);
//memset(ptr, 0, 128 * 1024);
};
get_mem_blk(pool_a); //works well
std::cout << "pass first test" << std::endl;
get_mem_blk(pool_b); //segment fault!
std::cout << "pass second test" << std::endl;
}
Here is the output:
pass first test
bash: line 7: 8617 Segmentation fault (core dumped) ./a.out
Simply adding -fsanitize=address,undefined reveals:
==26122==ERROR: AddressSanitizer: allocator is out of memory trying to allocate 0xa000000010 bytes
#0 0x7fe4dd7d3b3f in operator new[](unsigned long, std::nothrow_t const&) (/usr/lib/x86_64-linux-gnu/libasan.so.6+0xb4b3f)
#1 0x5577f383c5b8 in boost::default_user_allocator_new_delete::malloc(unsigned long) /home/sehe/custom/boost_1_76_0/boost/pool/pool.hpp:97
#2 0x5577f383c5b8 in boost::pool<boost::default_user_allocator_new_delete>::ordered_malloc_need_resize() /home/sehe/custom/boost_1_76_0/boost/pool/pool.hpp:733
==26122==HINT: if you don't care about these errors you may set allocator_may_return_null=1
SUMMARY: AddressSanitizer: out-of-memory (/usr/lib/x86_64-linux-gnu/libasan.so.6+0xb4b3f) in operator new[](unsigned long, std::nothrow_t const&)
==26122==ABORTING
The problem seems to be that next_size multiplies the partition size. Indeed, the default value is "only" 32. You probably meant the behaviour you get with
boost::pool<> pool_b(1024 * 128, 5 * 8);
or similar.