Commit de42153e authored by Tom Stellard's avatar Tom Stellard
Browse files

Merging r234254: 

------------------------------------------------------------------------
r234254 | ericwf | 2015-04-06 16:03:01 -0700 (Mon, 06 Apr 2015) | 25 lines

[libcxxabi] Disallow Base to Derived conversions for catching pointers to members.

Summary:
I accidentally implemented the 4.11 [conv.mem] conversions for libc++abi in a recent patch. @majnemer pointed out that 5.13 [except.handle] only allows the pointer conversions in 4.10 and not those is 4.11. This patch no longer allows the following example code:

```c++
struct A {};
struct B : public A {};

int main() {
  try {
    throw (int A::*)0;
  } catch (int B::*) {
    // exception caught here.
  }
}
```

Reviewers: mclow.lists, jroelofs, majnemer

Reviewed By: majnemer

Subscribers: majnemer, cfe-commits

Differential Revision: http://reviews.llvm.org/D8845
------------------------------------------------------------------------

llvm-svn: 236866
parent 84c765b2

libcxxabi/src/private_typeinfo.cpp

+3 −5
Original line number Diff line number Diff line
@@ -473,11 +473,9 @@ bool __pointer_to_member_type_info::can_catch( 
    if (is_equal(__context, thrown_pointer_type->__context, false))

        return true;



    __dynamic_cast_info info = {__context, 0, thrown_pointer_type->__context, -1, 0};

    info.number_of_dst_type = 1;

    __context->has_unambiguous_public_base(&info, adjustedPtr, public_path);

    if (info.path_dst_ptr_to_static_ptr == public_path)

        return true;

    // [except.handle] does not allow the pointer-to-member conversions mentioned

    // in [mem.conv] to take place. For this reason we don't check Derived->Base

    // for Derived->Base conversions.



    return false;

}

libcxxabi/test/catch_member_data_pointer_01.cpp

+5 −10
Original line number Diff line number Diff line
@@ -72,7 +72,7 @@ void test2() 
    }

}



// Check that Base -> Derived conversions are allowed.

// Check that Base -> Derived conversions are NOT allowed.

void test3()

{

    try
@@ -90,14 +90,14 @@ void test3() 
    }

    catch (der1)

    {

        assert(false);

    }

    catch (md1)

    {

        assert(false);

    }

}



// Check that Base -> Derived conversions are allowed with different cv

// Check that Base -> Derived conversions NOT are allowed with different cv

// qualifiers.

void test4()

{
@@ -107,19 +107,14 @@ void test4() 
        assert(false);

    }

    catch (der2)

    {

    }

    catch (...)

    {

        assert(false);

    }



    try

    catch (der1)

    {

        throw &A::j;

        assert(false);

    }

    catch (der1)

    catch (md2)

    {

    }

    catch (...)

libcxxabi/test/catch_member_function_pointer_01.cpp

+110 −0
Original line number Diff line number Diff line
@@ -18,6 +18,20 @@ struct A 
typedef void (A::*mf1)();

typedef void (A::*mf2)() const;



struct B : public A

{

};



typedef void (B::*dmf1)();

typedef void (B::*dmf2)() const;



template <class Tp>

bool can_convert(Tp) { return true; }



template <class>

bool can_convert(...) { return false; }





void test1()

{

    try
@@ -50,8 +64,104 @@ void test2() 
    }

}







void test_derived()

{

    try

    {

        throw (mf1)0;

        assert(false);

    }

    catch (dmf2)

    {

       assert(false);

    }

    catch (dmf1)

    {

       assert(false);

    }

    catch (mf1)

    {

    }



    try

    {

        throw (mf2)0;

        assert(false);

    }

    catch (dmf1)

    {

       assert(false);

    }

    catch (dmf2)

    {

       assert(false);

    }

    catch (mf2)

    {

    }



    assert(!can_convert<mf1>((dmf1)0));

    assert(!can_convert<mf2>((dmf1)0));

    try

    {

        throw (dmf1)0;

        assert(false);

    }

    catch (mf2)

    {

       assert(false);

    }

    catch (mf1)

    {

       assert(false);

    }

    catch (...)

    {

    }



    assert(!can_convert<mf1>((dmf2)0));

    assert(!can_convert<mf2>((dmf2)0));

    try

    {

        throw (dmf2)0;

        assert(false);

    }

    catch (mf2)

    {

       assert(false);

    }

    catch (mf1)

    {

        assert(false);

    }

    catch (...)

    {

    }

}



void test_void()

{

    assert(!can_convert<void*>(&A::foo));

    try

    {

        throw &A::foo;

        assert(false);

    }

    catch (void*)

    {

        assert(false);

    }

    catch(...)

    {

    }

}



int main()

{

    test1();

    test2();

    test_derived();

    test_void();

}

libcxxabi/test/catch_multi_level_pointer.pass.cpp

+0 −2
Original line number Diff line number Diff line
@@ -140,6 +140,4 @@ int main() 
  generate_tests<int A::*, int A::*, 3>()();

  generate_tests<int A::*, void, 2>()();

  generate_tests<void, int A::*, 2>()();

  generate_tests<int Base::*, int Derived::*, 2>()();

  generate_tests<int Derived::*, int Base::*, 2>()();

}