* go-gcc.cc (Gcc_backend::immutable_struct): If IS_COMMON, set
	DECL_WEAK.
	(GCC_backend::immutable_struct_set_init): If IS_COMMON, clear
	DECL_WEAK.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@208301 138bc75d-0d04-0410-961f-82ee72b054a4