* symtab.h (Symbol::is_strong_undefined): Removed unused function.

	* symtab.h (Symbol::is_strong_undefined): Removed unused function.
	(Symbol::needs_plt_entry): Allow weak undefined symbols.
	(Symbol::needs_dynamic_reloc): Allow weak undefined symbols when
	building shared libraries.
	* testsuite/Makefile.am (weak_undef_nonpic_test): New target.
	(weak_undef_file1_nonpic.o, weak_undef_file2_nonpic.o)
	(weak_undef_lib_nonpic.so, alt/weak_undef_lib_nonpic.so): New targets.
	* testsuite/Makefile.in: Rebuild.
	* testsuite/weak_undef.h: New file.
	* testsuite/weak_undef_file1.cc: Add extra test cases.
	* testsuite/weak_undef_file2.cc: Likewise.
	* testsuite/weak_undef_test.cc: Likewise.