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delphi64-bitintegerdelphi-xe2typecast-operator

Integer() type cast doesn't work on Delphi 64-bit

I have the following piece of code:

inc(integer(DestPixel), DestDelta); //DestPixel: PColorRGB; DestDelta: integer;

This works fine on 32-bit platforms. If I change the platform to 64-bit in the compiler the compiler emits this error:

E2064 Left side cannot be assigned to

The problem seems to be in the integer() typecast. How can I fix the problem?

Solution

  • On the 64 bit platform, DestPixel is 8 bytes wide, Integer is 4 bytes and so the typecast is invalid. You can fix this problem by using NativeInt instead.

    inc(NativeInt(DestPixel), DestDelta);

    The NativeInt type is the same size as a pointer and so floats between 4 bytes and 8 bytes wide depending on the output target.

    Having said that, I personally would typecast with PByte because that more correctly describes the operation you are performing.

    inc(PByte(DestPixel), DestDelta);