Re: A FORTRAN 90/95 or C/C++ code While taking a conditional termination from the running of a code, should one deallocate (delete) all the memory that has been allocated upto that point? How important is it? Will appreciate your comments/thoughts.

In theory termination of the code will free up the memory. In practice it is good programming etiquette to deallocate what has been allocated when you are done with it. My experience has been primarily with FORTRAN.

> should one deallocate (delete) all the memory that has been allocated upto that point?

There is no requirement to do so. When the process is finished the operating system will return the memory for use by other processes.

> How important is it?

It is not important for performance.

It can have importance as a coding check. If you cannot easily free all allocated memory from the main controlling parts of you code it is probably an indicator of poor coding structure (but there are exceptions).

In C++, If you're working with STL containers then you don't have to worry about that, because the destructors are called automatically by the program. On the other hand, if you're allocating your own arrays with the operator new, then you have to release the memory with the operator delete when you're not going to use them anymore, otherwise you can have segmentation fault problems.