On 01/03/2018 11:31 AM, Marek Polacek wrote:
Here we are crashing because cxx_fold_indirect_ref got a POINTER_PLUS_EXPR
with offset > signed HOST_WIDE_INT and we tried to convert it to sHWI.
The matching code in fold_indirect_ref_1 uses uHWIs so I've followed suit.
But that code now also uses poly_uint64 and I'm not sure if any of the
constexpr.c code should use it, too. But this patch fixes the ICE.
This doesn't look right to me, but it doesn't help that the test case
invokes UB.
+typedef int V __attribute__ ((__vector_size__ (16)));
+V a;
+
+int
+main ()
+{
+ reinterpret_cast <int *> (&a)[-1] += 1;
+}
one could make this code well formed with (I think)
typedef int V __attribute__ ((__vector_size__ (16)));
V a[2];
int main ()
{
return reinterpret_cast <int *> (&a[1])[-1];
}
That should access the final element of the a[0] vector.
nathan
--
Nathan Sidwell
