C语言 '(' 标记之前的预期声明说明符或 '...'？
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Expected declaration specifiers or '...' before '(' token?
提问by Kevin Dong
#include <stdio.h>
#include <stdlib.h>
#include <windows.h>
/// Global Variables
HANDLE ConsoleHandle;
int RGB (int R, int G, int B); // line 8
int Set_Color (int RGB_Fore, int RGB_Back);
int main (void)
{
// Get Handle
ConsoleHandle = GetStdHandle(STD_OUTPUT_HANDLE);
char Str [32] = "Happy New Year.\n";
printf("%s", Str);
system("pause>nul");
return 0;
}
int RGB (int R, int G, int B) // line 21
{
return (R*4 + G*2 + B);
}
int Set_Color (int RGB_Fore, int RGB_Back)
{
SetConsoleTextAttribute(ConsoleHandle, RGB_Fore*8 + RGB_Back);
}
The TDM-GCC reported:
TDM-GCC 报告说：
| line | Message
| 08 | error: expected declaration specifiers or '...' before '(' token
| 21 | error: expected declaration specifiers or '...' before '(' token
Why? How to solve this problem? Thanks
为什么？如何解决这个问题呢？谢谢
采纳答案by Shafik Yaghmour
Looks like RGBis a macro, if you rename the function that error will go away. Also Set_Colorneeds to return a value you have it defined to return an intbut you fall of the end of the function without returning anything.
看起来RGB是一个宏，如果你重命名这个错误就会消失的函数。还Set_Color需要返回一个你定义为返回的值，int但是你在函数的末尾没有返回任何东西。
If you attempted to use the value of Set_Colorwithout an explicit return that would be undefined behavioras per the C99 draft standard section 6.9.1Function definitionsparagraph 12:
如果您尝试在Set_Color没有显式返回的情况下使用 的值，则根据 C99 草案标准部分功能定义第12段将是未定义行为：6.9.1
If the } that terminates a function is reached, and the value of the function call is used by the caller, the behavior is undefined.
如果到达终止函数的 }，并且调用者使用了函数调用的值，则行为未定义。
and this is undefinedin C++regardless of whether you attempt to use the return value or not.
无论您是否尝试使用返回值，这在C++ 中都是未定义的。
