Deleting objects from memory

Question

My company uses a this piece of code to delete ALL objects from memory.
But because of the catch(...) I wonder what happens if the destructor of that object fails (AV)? Is it ok to catch everything silently? If the destructor failed, don't we want to know about this?

#define DELNULL(p) \
{                  \
if (p)             \
   {               \
   try             \
      {delete p;}  \
   catch (...)     \
      {}           \
   p = NULL;       \
   }               \
}                  \

AFAIK,. it is allowed to delete a null pointer, no need to test it. — Max, Sep 24 '19 at 13:08
What version of C++ does your company use? This code should no longer even need to be used now that we have smart pointers. `new` and `delete` really don't have a place in modern C++ (except for placement new) — NathanOliver, Sep 24 '19 at 13:09
You should probably ask this on Code Review since it is 'working' code. — dandan78, Sep 24 '19 at 13:12
I'd improve it by doing: `#define DELNULL(p) do { delete p; p = nullptr; } while(false)` — Eljay, Sep 24 '19 at 13:14
Also this is not safe: destructors should never throw to begin with: https://stackoverflow.com/questions/130117/throwing-exceptions-out-of-a-destructor — freakish, Sep 24 '19 at 13:14
@freakish - Yes, definitivelly. But you used "should not" in your phrase. So, what if? — Gabriel, Sep 24 '19 at 13:15
@WeGoToMars as I said: your code **does not** make it safe. Your app may still crash. See the linked answer. — freakish, Sep 24 '19 at 13:15
@WeGoToMars and I think it will crash if for example two different destructors in inheritance chain throw. So I strongly suggest to remove this code and just enforce "noexcept" policy for destructors. — freakish, Sep 24 '19 at 13:18

score 1 · Accepted Answer · answered Sep 24 '19 at 13:31

Is it ok to catch everything silently?

It is generally not OK to silently catch everything (it's rarely OK to silently catch anything). It would be often useful to know about errors.

In some cases it may be better to not let exceptions propagate. For example, if we are in a function called from C, or if we don't want to terminate, and are in destructor or in a noexcept function. But, it would be better to fall back to some other form of error reporting rather than swallowing them silently.

P.S. if (p) check is redundant and can be safely removed.

Deleting objects from memory

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