An exception gets thrown twice from a constructor with a function-try-block

Question

Why does the following exception thrown from the constructor of class A get caught twice, first by the catch within the constructor itself and second time by the catch in th

Answer 1

Function-try-blocks in a constructor cannot prevent exceptions. Once an exception occurs in a constructor, you have no object, and the exception must propagate. The only thing the function-try-block can do is some local clean-up.

Constructors are indeed a very special animal with regards to function-try-blocks.

Cf. C++11 15.3/14:

The currently handled exception is rethrown if control reaches the end of a handler of the function-try-block of a constructor or destructor.

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Tl;dr: Do not use function-try-blocks, ever.