add this  "||mapinfos[i].flags & MAP_ELF" first then

1.============
	for(seg = 0, i = 0; i < num; i++) {
	  	if(!(mapinfos[i].flags & PG_HWMAPPED) ||
			(nodumpmem && !(mapinfos[i].flags & MAP_STACK 
||mapinfos[i].flags & MAP_ELF)) ) {
			continue;
		}
		if ( (nodumpphys && (mapinfos[i].flags & MAP_PHYS) && !(mapinfos[i].flags & MAP_ANON)) ) {
			continue;
		}

		/* if we only want to dump the offending tid's stack */
		if(cur_tid_only && (mapinfos[i].flags & MAP_STACK) && 
			!OFFENDING_THREAD(cur_tid_base, cur_tid_size, &mapinfos[i])) {
			continue;
		}

		memcpy(&mem[seg], &mapinfos[i], sizeof(*mem));
		seg++;
	}

2.==============
add || mem[j].flags & MAP_ELF

for ( j = 0; j < seg; j++ ) {
		if ( lseek( fd, mem[j].vaddr, SEEK_SET ) == -1 )
			goto bailout;
		if ( mem[j].flags & MAP_STACK || mem[j].flags & MAP_ELF)
			dump_stack_memory( fd, fp, &mem[j], &coresize );
		else
		  if (!nodumpmem)
			dump_memory( fd, fp, &mem[j], &coresize );
	}

this should work.
if this doesn't work then it is possible that some areas we dumped twice, take a look dump_stack_memory should tell us.