21:3: error: implicit declaration of function 'ACPI_PTR' [-Werror=implicit-function-declaration]
时间: 2023-11-19 18:54:56 浏览: 40
这个错误是因为在代码中使用了一个未声明的函数ACPI_PTR,导致编译器无法识别该函数。解决方法是在代码中显式地声明该函数或者包含该函数所在的头文件。如果该函数是在外部库中定义的,需要将该库链接到代码中。另外,也可以通过在编译时加上-Wno-error=implicit-function-declaration选项来忽略该错误。
相关问题
error: implicit declaration of function 'ACPI_PTR'
The error message "implicit declaration of function 'ACPI_PTR'" indicates that you are trying to use a function called 'ACPI_PTR' without declaring it or including the necessary header file.
To resolve this issue, you need to include the appropriate header file that declares the 'ACPI_PTR' function. The header file may vary depending on the context and the specific library or API you are using.
First, check the documentation or reference material for the library or API you are using to find out which header file you need to include. Once you have identified the correct header file, make sure to include it at the top of your source file before using the 'ACPI_PTR' function. For example:
```c
#include <acpi.h> // or the appropriate header file
// Rest of your code
// Use the 'ACPI_PTR' function here
```
By including the correct header file, you should be able to resolve the "implicit declaration" error and properly use the 'ACPI_PTR' function.
error: implicit declaration of function ‘unget_wch’ [-Werror=implicit-function-declaration]
这个错误是由于在代码中使用了未声明的函数"unget_wch"导致的。编译器在编译过程中会检查函数的声明和定义是否匹配,如果找不到函数的声明,就会报出这个错误。
要解决这个错误,你需要在代码中添加函数"unget_wch"的声明。函数声明告诉编译器该函数的存在和参数类型,以便在使用该函数时进行正确的类型检查。
下面是一个示例的函数声明:
```c
int unget_wch(wint_t wc);
```
你可以根据实际情况修改函数声明中的返回类型和参数类型。确保在使用"unget_wch"函数之前,先进行正确的声明。