[Bug c++/53294] New: Optimize out some exception code

[glisse at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53294

             Bug #: 53294
           Summary: Optimize out some exception code
    Classification: Unclassified
           Product: gcc
           Version: 4.8.0
            Status: UNCONFIRMED
          Severity: enhancement
          Priority: P3
         Component: c++
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: glisse@gcc.gnu.org


Hello,

it would be great if the compiler could transform code like:

  try {
    throw 42;
  } catch(...) {
  }

into nothing (or in practice into a simple goto, since there will be code
around). It already knows to remove the code after "throw", it could statically
check that the exception will be caught locally and thus skip the __cxa_throw,
__cxa_begin_catch game.

Filed as C++ front-end, but it might be for the middle-end, since it would be
best if this optimization happened after inlining.