Incompatible Type for Argument 1

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Views: 1765 | Replies: 3 | Solved

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Join Date: Nov 2007

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RexxX

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Incompatible Type for Argument 1

Nov 18th, 2007

Also argument 2 makes integer from a pointer with a cast. One argument is a struct declared in an included library. It's declared like:

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struct pixelst *lzwArr;

lzwArr = (struct pixelst *) malloc(pixels); // pixels is an int

the second argument is an unsigned int 2D array. It's used in a function to store hex numbers. It's declared like:

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 int dlzwHeight = (int)lzwArr[0].height; //cast to int
        int dlzwWidth = (int)lzwArr[0].width; //cast to int

        unsigned int dlzwArr[ dlzwHeight ][ dlzwWidth ];
        dlzwFun(lzwArr, dlzwArr); //line giving the error

The reason I cast the struct variables to int is because they start as hex numbers. Can you see the problem from the code here?

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Join Date: Dec 2005

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Salem

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Re: Incompatible Type for Argument 1

Nov 18th, 2007

> The reason I cast the struct variables to int is because they start as hex numbers
This makes no sense at all.
What does this do?

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int a = 10;
int b = 0xa;
printf( "%d %d\n", a, b );

The fact that the constant was written in hex, or was read from a string in hex and converted to an int doesn't make a bean of difference.

> unsigned int dlzwArr[ dlzwHeight ][ dlzwWidth ];
You appear to be trying to declare a variable sized array. If your compiler allows this (at all), it is non-standard behaviour.

> lzwArr = (struct pixelst *) malloc(pixels);
1. You cast the result of malloc. There is no need to do this if your C program is correct, and it hides problems if your C program is wrong.
2. The form should be
lzwArr = malloc ( pixels * sizeof *lzwArr ); I'm guessing you allocated a hell of a lot less than you though you had, and have been trashing lots of memory as a result.