[Bug c++/60096] New: c++11 lambda reference capture mistake

2014-02-06 Thread feng.w...@uni-ulm.de 
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60096

Bug ID: 60096
   Summary: c++11 lambda reference capture mistake
   Product: gcc
   Version: 4.8.2
Status: UNCONFIRMED
  Severity: normal
  Priority: P3
 Component: c++
  Assignee: unassigned at gcc dot gnu.org
  Reporter: feng.w...@uni-ulm.de

considering the following code:
[code]
#include iostream

int main()
{
std::cout 
[]( int x )
{
return [](int y)
{
return x+y;
}(2);
}(5)
   \n;
std::cout  []( int x )
 {
return [x](int y)
{
return x+y;
};
 }(2)(5)
   \n;
std::cout  []( int x )
 {
return [x](int y)
{
return x+y;
};
 }(2)(5)
   \n;

return 0;
}
[/code]
the output produced by g++4.8 and g++4.9 is 
[output]
7
10
7
[/output]
while the expected output is 
[output]
7
7
7
[/output]

[Bug c++/60096] c++11 lambda reference capture mistake

2014-02-06 Thread feng.w...@uni-ulm.de 
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60096

--- Comment #2 from Feng Wang feng.w...@uni-ulm.de ---
(In reply to Jonathan Wakely from comment #1)
 This looks invalid to me, you return a closure that holds a dangling
 reference to a function parameter that has gone out of scope.

Sorry, my fault. I should have been using a const reference

[]( int const x )
{
  return [x](int const y)
  {
return x+y;
  };
}  
(2)(5);

[Bug c++/60096] c++11 lambda reference capture mistake

2014-02-06 Thread feng.w...@uni-ulm.de 
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60096

Feng Wang feng.w...@uni-ulm.de changed:

   What|Removed |Added

 Status|UNCONFIRMED |RESOLVED
 Resolution|--- |INVALID

--- Comment #3 from Feng Wang feng.w...@uni-ulm.de ---
mark as invalid.