re PR middle-end/71002 (-fstrict-aliasing breaks Boost's short string optimization...

re PR middle-end/71002 (-fstrict-aliasing breaks Boost's short string optimization implementation)

2016-06-29  Richard Biener  <rguenther@suse.de>

	PR middle-end/71002
	* alias.c (component_uses_parent_alias_set_from): Handle
	type punning through union accesses by using the union alias set.
	* gimple.c (gimple_get_alias_set): Remove union type punning case.

	c-family/
	* c-common.c (c_common_get_alias_set): Remove union type punning case.

	fortran/
	* f95-lang.c (LANG_HOOKS_GET_ALIAS_SET): Remove (un-)define.
	(gfc_get_alias_set): Remove.

	* g++.dg/torture/pr71002.C: Adjust testcase.

From-SVN: r237839