+
+/* .weakref x, y sets x as an alias to y that, as long as y is not
+ referenced directly, will cause y to become a weak symbol. */
+void
+s_weakref (int ignore ATTRIBUTE_UNUSED)
+{
+ char *name;
+ char delim;
+ char *end_name;
+ symbolS *symbolP;
+ symbolS *symbolP2;
+ expressionS exp;
+
+ name = input_line_pointer;
+ delim = get_symbol_end ();
+ end_name = input_line_pointer;
+
+ if (name == end_name)
+ {
+ as_bad (_("expected symbol name"));
+ *end_name = delim;
+ ignore_rest_of_line ();
+ return;
+ }
+
+ symbolP = symbol_find_or_make (name);
+
+ if (S_IS_DEFINED (symbolP) || symbol_equated_p (symbolP))
+ {
+ if (!S_IS_VOLATILE (symbolP))
+ {
+ as_bad (_("symbol `%s' is already defined"), name);
+ *end_name = delim;
+ ignore_rest_of_line ();
+ return;
+ }
+ symbolP = symbol_clone (symbolP, 1);
+ S_CLEAR_VOLATILE (symbolP);
+ }
+
+ *end_name = delim;
+
+ SKIP_WHITESPACE ();
+
+ if (*input_line_pointer != ',')
+ {
+ *end_name = 0;
+ as_bad (_("expected comma after \"%s\""), name);
+ *end_name = delim;
+ ignore_rest_of_line ();
+ return;
+ }
+
+ input_line_pointer++;
+
+ SKIP_WHITESPACE ();
+
+ name = input_line_pointer;
+ delim = get_symbol_end ();
+ end_name = input_line_pointer;
+
+ if (name == end_name)
+ {
+ as_bad (_("expected symbol name"));
+ ignore_rest_of_line ();
+ return;
+ }
+
+ if ((symbolP2 = symbol_find_noref (name, 1)) == NULL
+ && (symbolP2 = md_undefined_symbol (name)) == NULL)
+ {
+ symbolP2 = symbol_find_or_make (name);
+ S_SET_WEAKREFD (symbolP2);
+ }
+ else
+ {
+ symbolS *symp = symbolP2;
+
+ while (S_IS_WEAKREFR (symp) && symp != symbolP)
+ {
+ expressionS *expP = symbol_get_value_expression (symp);
+
+ assert (expP->X_op == O_symbol
+ && expP->X_add_number == 0);
+ symp = expP->X_add_symbol;
+ }
+ if (symp == symbolP)
+ {
+ char *loop;
+
+ loop = concat (S_GET_NAME (symbolP),
+ " => ", S_GET_NAME (symbolP2), (const char *) NULL);
+
+ symp = symbolP2;
+ while (symp != symbolP)
+ {
+ char *old_loop = loop;
+ symp = symbol_get_value_expression (symp)->X_add_symbol;
+ loop = concat (loop, " => ", S_GET_NAME (symp),
+ (const char *) NULL);
+ free (old_loop);
+ }
+
+ as_bad (_("%s: would close weakref loop: %s"),
+ S_GET_NAME (symbolP), loop);
+
+ free (loop);
+
+ *end_name = delim;
+ ignore_rest_of_line ();
+ return;
+ }
+
+ /* Short-circuiting instead of just checking here might speed
+ things up a tiny little bit, but loop error messages would
+ miss intermediate links. */
+ /* symbolP2 = symp; */
+ }
+
+ *end_name = delim;
+
+ memset (&exp, 0, sizeof (exp));
+ exp.X_op = O_symbol;
+ exp.X_add_symbol = symbolP2;
+
+ S_SET_SEGMENT (symbolP, undefined_section);
+ symbol_set_value_expression (symbolP, &exp);
+ symbol_set_frag (symbolP, &zero_address_frag);
+ S_SET_WEAKREFR (symbolP);
+
+ demand_empty_rest_of_line ();
+}
projects / binutils-gdb.git / blobdiff