Hello. In a program i am writing, i have an array which size is equal to the number of nodes in my cluster. I made this array to keep an eye of the objects that each node has in his control and when i use it with the actual ranks of the nodes as positions ( *array[node_rank]=objects;*) it returns me an error and stops the execution: *rank 0 in job 10 Calliope_49755 caused collective abort of all ranks** ** exit status of rank 0: killed by signal 11 * However, i had freely used the variable /id/ or /node_rank/ to point out a specific action for a specific node since now and never had problems. If instead of using the ranks node as a pointer for the array, i use an integer i.e. 5, the program runs fine, but even now, 1 out of 7 executions, it returns me an error and stops. The action i am calling that keeps returning me the error is a simple abstraction (*array[id]--;*). Any ideas? PS. The array is 1d and is created by allocating memory, like this : *int *array = malloc(processes * sizeof(int));*