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4b8881abb4
Reordered struct members to not waste memory due to padding.
Before:
``` C
typedef struct {
uint8_t src_l2addr_len;
uint8_t dst_l2addr_len;
kernel_pid_t if_pid; // <-- 16 bit, is aligned to 16 bit
uint8_t flags;
uint8_t __padding_byte; // <-- Inserted to fulfill padding requirements
int16_t rssi; // <-- 16 bit, is NOT aligned to 16 bit
uint8_t lqi;
uint8_t __padding_byte2;// <-- Inserted to fulfill padding requirements
} gnrc_netif_hdr_t;
```
Now:
``` C
typedef struct {
uint8_t src_l2addr_len;
uint8_t dst_l2addr_len;
kernel_pid_t if_pid; // <-- 16 bit, is aligned to 16 bit
uint8_t flags;
uint8_t lqi;
int16_t rssi; // <-- 16 bit, is aligned to 16 bit
} gnrc_netif_hdr_t;
```
When build for the `bluepill` board, the new layout reduces the size by 2 bytes.
|
||
|---|---|---|
| .. | ||
| gomach | ||
| icmpv6 | ||
| ipv6 | ||
| lwmac | ||
| mac | ||
| netif | ||
| rpl | ||
| sixlowpan | ||
| tcp | ||
| icmpv6.h | ||
| ipv6.h | ||
| ndp.h | ||
| netapi.h | ||
| neterr.h | ||
| netif.h | ||
| netreg.h | ||
| nettest.h | ||
| nettype.h | ||
| pkt.h | ||
| pktbuf.h | ||
| pktdump.h | ||
| pktqueue.h | ||
| priority_pktqueue.h | ||
| rpl.h | ||
| sixlowpan.h | ||
| tcp.h | ||
| tftp.h | ||
| udp.h | ||