id	summary	reporter	owner	description	type	status	priority	milestone	component	version	resolution	keywords	cc
4553	Wrong structural reporting in systems with complex array equations	Francesco Casella	Patrick Täuber	"Consider this test case
{{{
model foo
  function f
    input Real x[2];
    output Real y[2];
    output Real z[2];
  algorithm
    y := {x[1], 2*x[2]};
    z := {x[1], -3*x[2]};
  end f;

  Real y[2], w[2];
  
equation
  (, y) = f(w);
  (, y) = f(w);
end foo;
}}}

OpenModelica-v1.13.0-dev-63-g453e1c7-64bit reports
{{{
[2] 23:25:37 Symbolic Error
Too few equations, under-determined system. The model has 2 equation(s) and 4 variable(s).

[3] 23:25:37 Translation Error
Internal error Transformation Module PFPlusExt index Reduction Method Pantelides failed!

[4] 23:25:37 Translation Error
post-optimization module wrapFunctionCalls (simulation) failed.
}}}

This system is singular (same equation repeated twice) but it is not underdetermined; there are 4 equations in 4 unknowns."	defect	closed	high	1.13.0	Backend		fixed