revert: re PR c++/71737 (ICE following 2x pack expansion in non-pack with template alias)

/c-family
2017-01-16  Paolo Carlini  <paolo.carlini@oracle.com>

	Revert:
     	2017-01-16  Paolo Carlini  <paolo.carlini@oracle.com>

	PR c++/71737
	* c-common.c (set_underlying_type): Always set DECL_ORIGINAL_TYPE.

/testsuite
2017-01-16  Paolo Carlini  <paolo.carlini@oracle.com>

	Revert:
        2017-01-16  Paolo Carlini  <paolo.carlini@oracle.com>

	PR c++/71737
	* g++.dg/cpp0x/pr71737.C: New.

From-SVN: r244496