fir.slice with a path component (z%re, z%im) was silently dropped by
FIRToMemRef. Since memref.reinterpret_cast cannot change element type,
layout must come from the projected box descriptor via
fir.box_dims/fir.box_elesize rather than the triplets. Only
complex-array projections are handled here —
sizeof(complex<T>)/sizeof(T) = 2 is always exact for divsi. Derived-type
component projections bail out to downstream FIR-to-LLVM lowering where
strides can be non-integer.
61aebacee7