Re: std::vector::operator[] throws exception

From:

James Kanze <kanze.james@neuf.fr>

Newsgroups:

comp.lang.c++.moderated

Date:

30 Jul 2006 13:05:54 -0400

Message-ID:

<eahu7n$nir$1@nntp.aioe.org>

Deane Yang wrote:
  > I was surprised to learn recently that code like

  > std::vector<int> v(3);
  > v[3] = 10;

  > compiled with VC++ 8.0 and the STL library that comes with it
  > throws an exception when run.

  > Does this conform to the official specification of std::vector?

The code has undefined behavior, so officially, anything the
compiler does conforms to the official specification. Normally,
I would expect a core dump, or whatever Windows calls its
equivalent.

Note that VC++ has a number of options for handling exceptions.
  From the little experience I have, the only one useful for
standards compliant code is /EHs. Is this what you are using?

  > No exception is thrown if compiled with cygwin gcc.

I get a core dump with g++ under Linux or Solaris. At least
with debug options turned on.

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