re PR c++/83217 (Compiler segfault: structured binding by reference to a templated type via a pointer)

	PR c++/83217
	* decl.c (cp_finish_decomp): If decl's type is REFERENCE_TYPE,
	call complete_type (TREE_TYPE (type)).

	* g++.dg/cpp1z/decomp33.C: New test.

From-SVN: r255702