Fix PR c++/42713

Fix PR c++/42713

gcc/cp/ChangeLog:
	PR c++/42713
	PR c++/42820
	* typeck.c (get_template_parms_of_dependent_type): Factorized
	this out of incompatible_template_type_parms_p
	(incompatible_dependent_types_p): Renamed
	incompatible_template_type_parms_p into this. Make it detect
	two incompatible dependent typedefs too.
	(structural_comptypes): Use incompatible_dependent_types_p.
	* pt.c (get_template_info):
	Handle BOUND_TEMPLATE_TEMPLATE_PARAM.

gcc/testsuite/ChangeLog:
	PR c++/42713
	PR c++/42820
	* g++.dg/template/typedef27.C: New test case.
	* g++.dg/template/typedef28.C: New test case.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@156316 138bc75d-0d04-0410-961f-82ee72b054a4