Reputation: 139
I have a compiling/linking error as follows:
Undefined symbols for architecture x86_64:
"_memory_table", referenced from:
_initialize in main.o
linker command failed with exit code 1
The problem may be in the .h file below. Have I done anything wrong with my typedef structs? The main.c simply calls initialize(). The initialize() fuction is below. For brevity, I have taken out all of the #define macros. Main is included further down the code.
Thanks.
//globals.h
#ifndef memory_manager_globals_h
#define memory_manager_globals_h
/******** Memory Table Entry Data Structure**********/
typedef struct
{
uint32_t block_address;
uint32_t next_free_block;
}mem_table_entry_t;
/******** Memory Table Data Structure**********/
typedef struct
{
mem_table_entry_t two_kib[8];
mem_table_entry_t one_kib[16];
mem_table_entry_t half_kib[32];
mem_table_entry_t quarter_kib[64];
mem_table_entry_t eighth_kib[128];
}mem_table_t;
extern mem_table_t memory_table;
#endif
...
//MAIN.C
#include <stdio.h>
#include "globals.h"
void initialize(void)
{
int block_count = 0; //
uint32_t dynamic_address = HEAP_START;
while(block_count <= INITIALIZE_BLOCK_COUNT)
{
if((block_count >= TWO_KIB_LO) && (block_count < TWO_KIB_HI))
{
memory_table.two_kib[block_count].block_address = HEAP_START;
dynamic_address = dynamic_address + 0x800;
memory_table.two_kib[block_count].next_free_block = dynamic_address;
block_count++;
}
...
[SOLVED] The correct format of the .h file should be as follows:
/******** Memory Table Entry Data Structure**********/
typedef struct
{
uint32_t block_address;
uint32_t next_free_block;
}mem_table_entry_t;
/******** Memory Table Data Structure**********/
typedef struct
{
mem_table_entry_t two_kib[8];
mem_table_entry_t one_kib[16];
mem_table_entry_t half_kib[32];
mem_table_entry_t quarter_kib[64];
mem_table_entry_t eighth_kib[128];
}mem_table_t;
mem_table_t memory_table;
extern mem_table_t memory_table;
Upvotes: 1
Views: 461
Reputation: 726997
You are missing a definition of memory_table
. The extern
line is a declaration, not a definition.
Add this line to your C file to fix the linking problem:
mem_table_t memory_table;
Upvotes: 3