PR c++/16924
	* config/i386/winnt.c (i386_pe_mark_dllexport): Set
	SYMBOL_REF_DECL.
	(i386_pe_mark_dllimport): Likewise.
	(i386_pe_encode_section_info): Likewise, when overriding
	dllimport attribute.

From-SVN: r85924