https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66451
Bug ID: 66451
Summary: Array not fully destructed if element destructor
throws exception
Product: gcc
Version: 4.9.2
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: jonathandodd at gmail dot com
Target Milestone: ---
If an array element throws during destruction, undestructed elements in that
array are not destructed. Other local variables are destructed. Clang calls
destructors on all automatic objects, regardless whether in or out of an array.
(And yes, I know throwing from destructors should be avoided, but that's hardly
the point ;p)
Relevant sections from standard
-------------------------------
s15.2:
As control passes from the point where an exception is thrown to a handler,
destructors are invoked for all automatic objects constructed since the try
block was entered. ...
An object of any storage duration whose initialization or destruction is
terminated by an exception will have destructors executed for all of its fully
constructed subobjects
s1.8:
A subobject can be ... an array element.
Test case
---------
#include <iostream>
#include <exception>
using namespace std;
class A {
public:
A(int new_a) : a(new_a) { }
~A() noexcept(false) {
cout << "a" << a <<".~A() ";
if(std::uncaught_exception())
cout << "Unwinding";
cout << endl;
if(a==4)
throw a;
}
int a;
};
int main()
{
try {
A a1(1), a2(2);
A arr[] = {3,4,5};
} catch(...) { }
}
Output (g++ 4.9.2)
------------------
a5.~A()
a4.~A()
a2.~A() Unwinding
a1.~A() Unwinding
Output (clang 3.5.0)
--------------------
a5.~A()
a4.~A()
a3.~A() Unwinding
a2.~A() Unwinding
a1.~A() Unwinding
