Struct size in C

gistfile1.c

#include <stdio.h>
#include <limits.h>

typedef struct _zval_struct zval;

typedef struct _zend_object {
	int *ce;
	int *properties;
	zval **properties_table;
	int *guards;
} zend_object;

struct tmp {
	char *val;
	int len;
};

typedef union _zvalue_value {
	long lval;
	double dval;
	struct {
		char *val;
		int len;
	} str;
	int *ht;
	zend_object obj;
} zvalue_value;

struct _zval_struct {
	zvalue_value value;
	unsigned int refcount__gc;
	unsigned char type;
	unsigned char is_ref__gc;
};

typedef struct _gc_root_buffer {
	struct _gc_root_buffer   *prev;
	struct _gc_root_buffer   *next;
	unsigned int        handle;
	union {
		zval                 *pz;
		const int *handlers;
	} u;
} gc_root_buffer;

typedef struct _zval_gc_info {
	zval z;
	union {
		gc_root_buffer       *buffered;
		struct _zval_gc_info *next;
	} u;
} zval_gc_info;


int main()
{
	char *cptr;
	int    a =  3;
	int   *b = &a;
	int  **c = &b;
	
	printf("Storage size for size_t : %lu \n", sizeof(size_t));
	printf("Storage size for char ptr : %lu \n", sizeof(cptr));
	printf("Storage size for **c : %lu \n", sizeof(c));
	printf("Storage size for unsigned char : %lu \n", sizeof(unsigned char));
	printf("Storage size for unsigned int : %lu \n", sizeof(unsigned int));
	printf("Storage size for unsigned long : %lu \n", sizeof(unsigned long));
	printf("Storage size for unsigned long long: %lu \n", sizeof(unsigned long long));
	printf("Storage size for double : %lu \n", sizeof(double));
	
	printf("\n");
	
	zvalue_value myStruct;
	
	printf("Storage size for struct zend_object : %lu \n", sizeof(zend_object));
	printf("Storage size for struct tmp : %lu \n", sizeof(struct tmp));
	printf("Storage size for union zvalue_value : %lu \n", sizeof(zvalue_value));
	printf("Storage size for struct _zval_struct : %lu \n", sizeof(struct _zval_struct));
	printf("Storage size for struct zval_gc_info : %lu \n", sizeof(zval_gc_info));
	
	
	return 0;
}