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From: "bootsarehax at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c++/52281] New: No warnings generated for unused captures
Date: Thu, 16 Feb 2012 15:38:00 -0000
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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52281

             Bug #: 52281
           Summary: No warnings generated for unused captures
    Classification: Unclassified
           Product: gcc
           Version: 4.6.2
            Status: UNCONFIRMED
          Severity: enhancement
          Priority: P3
         Component: c++
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: bootsarehax@gmail.com


I would expect the code:

int main()
{
  int i = 23;
  auto x = [&i]() {return 25;};
  x();
  return 0;
}

to issue a warning when compiled with -Wall -Wextra similar to unused
variables.

This seems similar to this:

struct foo {
  int operator()() { return 42;}
  int x;
};

gcc does not issue a warning here as well, although it might be useful.