如何在C中使用双宏

让我们看看我的代码T.T

我定义了宏，如下所示

这是我的宏头文件。宏.h

#define BUZZER_PWM                                  PWMA
#define BUZZER_PWM_CH                               0
#define ENABLE_PWM(pwm,ch)      (pwm)->POE |= PWM_POE_PWM##ch##_Msk     

并在另一个cfile中调用宏

ENABLE_PWM(BUZZER_PWM,BUZZER_PWM_CH);

我预测预编译后的结果是

PWMA -> POE |= PWM_POE_PWM0_Msk;

但是

结果是。 有什么解决办法吗

---

对不起，我的英语能力很差。

为了确保宏参数（特别是在您的情况下

蜂鸣器\u PWM\u CH

在串联之前得到扩展（

PWM\u POE\u PWM\CH\u Msk

）使用额外的宏

示例文件

macro.c

#define BUZZER_PWM                                  PWMA
#define BUZZER_PWM_CH                               0
#define ENABLE_PWM(pwm,ch)      ENABLE_PWM_(pwm,ch)
#define ENABLE_PWM_(pwm,ch)      (pwm)->POE |= PWM_POE_PWM##ch##_Msk     

/* expected expansion */
ENABLE_PWM(BUZZER_PWM,BUZZER_PWM_CH);

/* wrong expansion */
ENABLE_PWM_(BUZZER_PWM,BUZZER_PWM_CH);

扩展为

$ gcc -E macro.c
# 1 "macro.c"
# 1 "<built-in>"
# 1 "<command-line>"
# 31 "<command-line>"
# 1 "/usr/include/stdc-predef.h" 1 3 4
# 32 "<command-line>" 2
# 1 "macro.c"






(PWMA)->POE |= PWM_POE_PWM0_Msk;


(PWMA)->POE |= PWM_POE_PWMBUZZER_PWM_CH_Msk;

$gcc-E macro.c
#1“宏c”
# 1 ""
# 1 ""
# 31 ""
#1“/usr/include/stdc predef.h”1 3 4
# 32 "" 2
#1“宏c”
（PWMA）->POE |=PWM_POE_PWM0_Msk；
（PWMA）->POE |=PWM(POE)PWMBUZER(PWM)CHU Msk ;；

基本上与的重复。在写入头文件时，始终在文件顶部包括include-guard:

\ifndef MACRO\u H

和

\define MACRO\u H

然后在文件末尾：

\endif//MACRO\u H

$ gcc -E macro.c
# 1 "macro.c"
# 1 "<built-in>"
# 1 "<command-line>"
# 31 "<command-line>"
# 1 "/usr/include/stdc-predef.h" 1 3 4
# 32 "<command-line>" 2
# 1 "macro.c"






(PWMA)->POE |= PWM_POE_PWM0_Msk;


(PWMA)->POE |= PWM_POE_PWMBUZZER_PWM_CH_Msk;