Viewing file:  20040317-1.C (1.13 KB) -rw-r--r--
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/* { dg-do run } */
/* { dg-options "-O2" } */
/* Test provided by Brian Ryner in PR 14511. The alias analyzer was
not handling structures containing arrays properly. In this case,
the static cast was introducing two assignments of the form
this_6->_vptr.IFoo = &_ZTV4IFoo[2];
this_4->_vptr.IFoo = &_ZTV3Bar[2];
which were not considered to alias each other because the alias
analyzer was not computing a proper pointer to array elements.
Another related bug was the type based alias analyzer not computing
alias relations to _ZTV4IFoo and _ZTV3Bar. Since those variables
are read-only, it was disregarding alias information for them.
So, the memory tags for the two 'this' variables were not being
marked as aliased with these variables. Resulting in the two
assignments not aliasing each other.
This was causing the optimizers to generate a call to the virtual
method Foo() instead of the overloaded version. */
struct IFoo
{
virtual void Foo() = 0;
};
struct Bar : IFoo
{
void Foo() { }
};
int main(int argc, char **argv)
{
Bar* b = new Bar();
static_cast<IFoo*>(b)->Foo();
return 0;
}
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