SIGSEGV

If your program fails with

p4_error: interrupt SIGSEGV

the problem is probably not with MPI. Instead, check for program bugs including

1. Array overwrites or accesses beyond array bounds. Be particularly careful of a[size] in C, where a is declared as int a[size].
2. Invalid pointers, including null pointers.
3. Missing or mismatched parameters to subroutines or functions. Fortran users should check that all MPI calls include the integer error return parameter and that any status variable is dimensioned as an array of size MPI_STATUS_SIZE.