[Bug tree-optimization/91280] [8/9/10 Regression] ICE in get_constraint_for_component_ref, at tree-ssa-structalias.c:3259 since r260354

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91280

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |ASSIGNED
           Assignee|unassigned at gcc dot gnu.org      |rguenth at gcc dot 
gnu.org

--- Comment #1 from Richard Biener <rguenth at gcc dot gnu.org> ---
Hmm, this has earlier errors:

t.ii:123:20: error: invalid use of incomplete type ‘class
TensorMap<Trans_NS_Eigen_Tensor<int, 3, 0, int>, 0>’
  123 |   static const int NumInputDims = H<typename
ArgType::Dimensions>::value;
      |                    ^~~~~~~~~~~~

so - too much testcase reduction?

But yeah, I can see what goes wrong - get_constraint_for_component_ref
doesn't expect get_constraint_for_1 on the base, here MEM[&decl + 16],
to return multiple constraints but when decl has subvars then if
&decl + 16 is not exactly at a subvar we'll include the next as well.