error C2678

[_Flaviu]

Thank you Richard, that error has vanished, but I cannot try this code yet ... why do you say that this solution is not really correct ? The safe solution would be to overload |= operator, but I cannot do that into enum, right ?

[Lost User]

_Flaviu wrote:

why do you say that this solution is not really correct ?

Because, as I mentioned before, enums are used to indicate a set of possible values for an item. For example a class of type Car could contain an enum that indicates the manufacturer, such that the enum definition is:

enum manufacturer
{
AUDI = 1,
BMW,
DAIMLER,
MERCEDES,
// etc.
}

And you would never combine thos values in the car type variable. So, in your case you should use #define statements, which the compiler will be happy with.

[_Flaviu]

But this enum is not a part of any struct or class, is just defined into a header file, along with other several enum's ... and this enum has a lot of values, that is why I intend to avoid to translated as #define's ... I don't know what to do ...

[Lost User]

But the issue is, as I keep repeating, that this is not the correct way to use enums. If you want to combine flag values then use #define, if you want to select one value from a set then use enum. That is the rule for C and C++, and that is why the compiler complains about your code.

[_Flaviu]

Thank you Richard for your patience. BTW, is a legacy code, is not written by me. There will be more suitable to chnage this enum to a struct and where to overload |= operator ?

[Lost User]

Why would you change it to a struct, it only requires a single integer variable to hold all the flags.

int flags = FILE_READONLY | FILE_HIDDEN;
flags |= FILE_SYSTEM;

[_Flaviu]

So the finest solution is to take these values from enum and put them as #defines. I will do this change.

[_Flaviu]

I am afraid that I cannot change that enum into #defines, because I have:

na->flags |= flag;

where

FILE_FLAGS flag;

and na is struct level1, and inside this level1 struct, I have

struct level1
{
FILE_FLAGS flags;
....
};

I have entered in some deadlock ? Please help me to solve this error ...

[Victor Nijegorodov]

Try to declare both flags and flag as int

[_Flaviu]

Yes, but FILE_FLAGS is enum with int values ...

[Victor Nijegorodov]

Then, as Richard already suggested replace this enum with a set of #define.

[_Flaviu]

Agree, but that enum is a part of another struct ... so, how can I put as part of a struct several #defines ?

[Lost User]

Of course you can change it to #defines. The definition of FILE_FLAGS then becomes an int type. And then the rest of the code should compile correctly.

[_Flaviu]

I am not get something, so forgive me. I have moved those enum values as #defines, but of course, now I get error from struct: doesn't know who is FILE_FLAGS flags; from level1 struct.

/*
typedef enum {
FILE_READONLY = 0x00000001,
FILE_HIDDEN = 0x00000002,
FILE_SYSTEM = 0x00000004,

FILE\_DIRECTORY = 0x00000010,
FILE\_ARCHIVE = 0x00000020,
FILE\_DEVICE = 0x00000040,
FILE\_NORMAL = 0x00000080,

FILE\_TEMPORARY = 0x00000100,

....
.....

}FILE_FLAGS;
*/

#define FILE_READONLY = 0x00000001
#define FILE_HIDDEN = 0x00000002
#define FILE_SYSTEM = 0x00000004

of course, FILE_FLAGS enum has disappeared ... obviously, I don't understood something ... but what ?

struct level1
{
FILE_FLAGS flags; // <-- error
....
};

[Victor Nijegorodov]

_Flaviu wrote:

struct level1 { FILE_FLAGS flags; // <-- error .... };

Try

struct level1
{
int flags; // <-- error
....
};

[_Flaviu]

Ok, but even flag is comming as function parameter, just like this:

static void SomeFunction(level1* na, FILE_FLAGS flag)
{
....
na->flags |= ~flag;
....
}

So, I guess I cannot give up FILE_FLAGS enum ... don't I ?

[Victor Nijegorodov]

Change this parameter to be

static void SomeFunction(level1* na, int flag)
{

[Lost User]

Add this line somewhere before the first reference to FILE_FLAGS :

typedef int FILE_FLAGS;

[_Flaviu]

I encounter another error if I made these modifications:

data->com = na->flags & ATTR_IS_COMPRESSED; // <-- error C2059: syntax error : '='

(where data->com is int) because now ATTR_IS_COMPRESSED is #define, not part of enum FILE_FLAGS ...

[Lost User]

What is data->com?

_Flaviu wrote:

because now ATTR_IS_COMPRESSED is #define, not part of enum FILE_FLAGS

That is not the reason. I can only assume that you have done a partial change and some parts of your code are still incorrect. If you still have the FILE_FLAGS enum then it is going to cause problems. It would probably help if you showed all the code portions that are connected. It is difficult to be certain of the answers when looking at only a single line of code.