NXC: array init faulty if global, ok if it's local!

[HaWe]

hi,
this code works:

Code: Select all

task main(){
  int  werte[8] = {1, 2, 3, 4, 5, 6, 7, 8};

  for (int i=0; i<8; i++) NumOut(0, i*8, werte[i]);

  while (true);
}

this doesn't (shows only 0's all over):

Code: Select all

int  werte[8] = {1, 2, 3, 4, 5, 6, 7, 8};

task main(){

  for (int i=0; i<8; i++) NumOut(0, i*8, werte[i]);

  while (true);
}

[ronmcrae]

The initialization should have either a size defined (i.e. [8]) OR it should have empty brackets [] and a list of elements to initialize the array. For the latter option the length of the list infers the size of the array.

Ron.

[HaWe]

thx, you're right, this works:

Code: Select all

int  werte[] = {1, 2, 3, 4, 5, 6, 7, 8};

task main(){

  for (int i=0; i<8; i++) NumOut(0, i*8, werte[i]);

  while (true);
}

But this does work as well if it's defined local
int werte[8] = {1, 2, 3, 4, 5, 6, 7, 8};
?

[muntoo]

But this does work as well if it's defined local
int werte[8] = {1, 2, 3, 4, 5, 6, 7, 8};
?

'Cause, IIRC, John doesn't want to implement:

Code: Select all

int foo[8];

task main()
{
    //...
}

[afanofosc]

I don't understand muntoo's comment. You can do what he showed in his example. It is correctly initialized to 8 zeros.

What Doc has experienced is a bug/known issue. If you specify a size for an array it generates code to initialize the array to N zeros or empty elements of whatever type your array is. If you also provide an initializer in braces then it acts differently depending on whether it is a global or a local. If it is a global then the array is initialized via static values in the dataspace portion of the RXE. Locals need to be initialized at run time.

Bottom line is I need to fix this and will try to do so in the next release. For now, if you provide an initializer then leave off the size. That's standard C syntax and it works right in NXC. Using both an initializer and a size in the brackets is also standard C syntax but it does not work right in NXC for global variables so avoid this syntax in this situation.

John Hansen

[muntoo]

Errr... nevermind what I said.