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Date: Fri, 03 Oct 2014 12:36:00 -0000
Message-ID: <CAH6eHdQWTr85CpbpGFeFahg+h7cT8QZmcGjirJ3XoFhtWYHO=Q@mail.gmail.com>
Subject: Re: std::string clobbers memory when compiling without optimizations
From: Jonathan Wakely <jwakely.gcc@gmail.com>
To: =?UTF-8?Q?Henrik_Mannerstr=C3=B6m?= <henrik.mannerstrom@gmail.com>
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On 3 October 2014 11:30, Henrik Mannerstr=C3=B6m wrote:
> On 10/03/2014 01:20 PM, Jonathan Wakely wrote:
>> My guess is that Sigma holds a dangling reference to some temporary
>> object that has gone out of scope, and the function call t2s
>> overwrites that stack memory, then when you return to main you go
>> through the dangling reference.
>>
>> Are you sure you're using the Eigen types correctly?
> You are right, the auto type does not force the evaluation of Sigma,
> which leaves the dangling reference. Yet again I get burned by trying to
> combine Eigen and C++11. How would you classify this, could you call it
> a bug in Eigen, or just incompatibility with C++11?

As Marc says, expression templates are often incompatible with 'auto',
that doesn't mean Eigen is incompatible with C++11 in general.