re PR debug/65549 (crash in htab_hash_string with -flto -g)

2015-06-02  Richard Biener  <rguenther@suse.de>

	PR debug/65549
	* dwarf2out.c (lookup_context_die): New function.
	(resolve_addr): Avoid forcing a full DIE for the
	target of a DW_TAG_GNU_call_site during late compilation.
	Instead create a stub DIE without a type if we have a
	context DIE present.

	* g++.dg/lto/pr65549_0.C: New testcase.

From-SVN: r224029