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cconstantsinitializer

Why do I get an error about the initializer not being a constant?

I am using the following code.

const int X_ORIGIN = 1233086;             
const int Y_ORIGIN = -4728071;              
const int Z_ORIGIN = 4085704;
const int xyzOrigin[NUM_DIMENSIONS] = {X_ORIGIN, Y_ORIGIN, Z_ORIGIN};

When I compile it, GCC gives me the following error.

Transformations.h:16:1: error: initializer element is not constant

What does that mean? How can I fix my code?

Solution

  • You can't do this at global scope in C, only at local scope, i.e. within a function:

    #define NUM_DIMENSIONS 3

const int X_ORIGIN = 1233086;             
const int Y_ORIGIN = -4728071;              
const int Z_ORIGIN = 4085704;

const int xyzOrigin[NUM_DIMENSIONS] = {X_ORIGIN, Y_ORIGIN, Z_ORIGIN}; // FAIL

void foo(void)
{
    const int xyzOrigin[NUM_DIMENSIONS] = {X_ORIGIN, Y_ORIGIN, Z_ORIGIN}; // OK
}

    Alternatively you could compile the code as C++ rather than C.