I have the following program code in a header file for debugging purposes. My intention is to decide during compile time that which messages should be printed out to console port or not print them at all if program is not compiled in debug mode.
#define ALL 0xffffffff
#define ENABLED (ERROR | WARNING | INFO) //Enabled error messages which needs to be printed out.
//Error msg types
#define ERROR 0x1ul
#define WARNING 0x2ul
#define INFO 0x4ul
#define DBG 0x10ul
#define ENTER 0x20ul
#define STORAGE 0x40ul
#define BOND_MANAGER 0x80ul
#define ANCS_EVENT 0x100ul
#define NOTIF_EVENT 0x200ul
#define BLE_EVENT 0x400ul
#define ANCS_APP 0x800ul
#define BLE 0x1000ul
#define PERIPHERALS 0x2000ul
#define PWM 0x4000ul
#define LEDS 0x8000ul
#define DebugMsgStr(a,b) do { \
if (a & ENABLED) \
simple_uart_putstring(b); \ //print to console port
}while(0)
#define DebugMsg(a,...) do { \
if (a & ENABLED) {\
uint8_t data[100]; \
snprintf(data,100,"%x - %x - %x",a,ENABLED,a&ENABLED); \ //These two lines only used for debugging the debug_printf
simple_uart_putstring(data); \ //These two lines only used for debugging the debug_printf
snprintf(data,100,__VA_ARGS__); \
simple_uart_putstring(data); }\ //print to console port
}while(0)
I print messages in the code like:
DebugMsg(ERROR| BLE ,"[ERROR-BLE]This should be seen",..);
DebugMsg(DBG | BLE ,"[DBG-BLE]This should not been logged",..);
Last message should only be logged when either DBG level or module BLE debugging is enabled. Despite DBG level is not enabled currently, i see the following logs:
8010 - 7 - 8000[LEDS-DBG] effect_counter:2
1010 - 7 - 10[BLE-DBG] Timer Tick: 0x0000745d
so
0x8010 & 0x7 == 0x8000.
0x1010 & 0x7 == 0x10
How this could happen? I am using arm-gcc for compiling to cortex-m0 nrf51822 Nordic chip. Also there is a dissasambly snippet, but do not seen anything special, just if(a&ENABLED) is not compiled at all.
DebugMsg(DBG | BLE,"[BLE-DBG] Timer Tick: 0x%08x\r\n",currentTime);
R7 --> this probably contains a pointer to currentTime variable
0001587a: adds r1, r7, #0 -->r1 = r7
0001587c: adds r1, #12 -->r1 = r1+12
0001587e: ldr r2, [pc, #248] ; (0x15978 <ble_ancs_c_connection_moretriage_timer+272>)
00015880: ldr r3, [pc, #248] ; (0x1597c <ble_ancs_c_connection_moretriage_timer+276>)
00015882: movs r0, #7 --> r0 -ba 0x7
00015884: str r0, [sp, #0] --> save to stack
00015886: movs r0, #16 -->r0 ->ba 0x10
00015888: str r0, [sp, #4] --> save to stack
0001588a: adds r0, r1, #0 --> r0 = r1
0001588c: movs r1, #100 ; 0x64 --> r1 = 100
0001588e: bl 0x22c74 <snprintf>
00015892: adds r3, r7, #0
00015894: adds r3, #12
00015896: adds r0, r3, #0
00015898: bl 0x21a08 <simple_uart_putstring>
0001589c: ldr r3, [r7, #112] ; 0x70
0001589e: adds r1, r7, #0
000158a0: adds r1, #12
000158a2: ldr r2, [pc, #220] ; (0x15980 <ble_ancs_c_connection_moretriage_timer+280>)
000158a4: adds r0, r1, #0
000158a6: movs r1, #100 ; 0x64
000158a8: bl 0x22c74 <snprintf>
000158ac: adds r3, r7, #0
000158ae: adds r3, #12
000158b0: adds r0, r3, #0
000158b2: bl 0x21a08 <simple_uart_putstring>
Thanks in advance.
DebugMsg(DBG | BLE ,"[ERROR-BLE]This should be seen",..) is expanded as
if (DBG | BLE & ENABLED) ...
which becomes
if (0x10ul | 0x1000ul & 0x07)
but & has higher precedence than | so this is parsed as
if (0x10 | (0x1000 & 0x07))
which is always true.
You should change the marco to
#define DebugMsgStr(a,b) do { \
if ((a) & ENABLED) \