Is there any guarantee for the order in which C++ stack variables are destroyed

Question

Consider the following code:

{
  std::auto_ptr<Something> p1(pSomePointer);
  std::auto_ptr<Something> p2(pSomeOtherPointer);
  ...
}

Is there any guarantee that p2 destructor will be called before p1's when exiting the scope? Common sense says that the stack variables should be destroyed from top of the stack first but C++ compiler can reorder assignments.

score 11 · Answer 1 · answered Nov 12 '10 at 14:29

11

Yes, they are destroyed in order opposite to the construction order - objects constructed last will be destroyed first. C++ guarantees this.

answered Nov 12 '10 at 14:29

sharptooth

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...and not only for stack variables. – sbi Nov 12 '10 at 14:30
@sbi: Yes, and the latter can lead to all sorts of bugs if care is not taken. – sharptooth Nov 12 '10 at 14:31
@sbi what other variables are we talking about? Global? – Elemental Nov 12 '10 at 15:41
@Elemental: Global variable order of destruction is implementation dependent. – bjskishore123 Nov 12 '10 at 16:17
1

@Elemental: Yes, globals and (namespace-scope or class-scope) statics. – sbi Nov 12 '10 at 16:25

Is there any guarantee for the order in which C++ stack variables are destroyed

1 Answers1