/* read.c - read a source file -
Copyright 1986, 1987, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997,
- 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005
+ 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006
Free Software Foundation, Inc.
This file is part of GAS, the GNU Assembler.
{"xref", s_ignore, 0},
{"xstabs", s_xstab, 's'},
{"warning", s_errwarn, 0},
+ {"weakref", s_weakref, 0},
{"word", cons, 2},
{"zero", s_space, 0},
{NULL, NULL, 0} /* End sentinel. */
*p = 0;
symbolP = symbol_find_or_make (name);
- if (S_IS_DEFINED (symbolP) && !S_IS_COMMON (symbolP))
+ if ((S_IS_DEFINED (symbolP) || symbol_equated_p (symbolP))
+ && !S_IS_COMMON (symbolP))
{
- symbolP = NULL;
- as_bad (_("symbol `%s' is already defined"), name);
- *p = c;
- ignore_rest_of_line ();
- goto out;
+ if (!S_IS_VOLATILE (symbolP))
+ {
+ symbolP = NULL;
+ as_bad (_("symbol `%s' is already defined"), name);
+ *p = c;
+ ignore_rest_of_line ();
+ goto out;
+ }
+ symbolP = symbol_clone (symbolP, 1);
+ S_SET_SEGMENT (symbolP, undefined_section);
+ S_SET_VALUE (symbolP, 0);
+ symbol_set_frag (symbolP, &zero_address_frag);
+ S_CLEAR_VOLATILE (symbolP);
}
size = S_GET_VALUE (symbolP);
{
S_SET_VALUE (symbolP, (valueT) size);
S_SET_EXTERNAL (symbolP);
+ S_SET_SEGMENT (symbolP, bfd_com_section_ptr);
#ifdef OBJ_VMS
{
extern int flag_one;
}
S_SET_EXTERNAL (sym);
+ S_SET_SEGMENT (sym, bfd_com_section_ptr);
mri_common_symbol = sym;
#ifdef S_SET_ALIGN
*p = 0;
symbolP = symbol_find_or_make (name);
- /* FIXME-SOON I pulled a (&& symbolP->sy_other == 0 &&
- symbolP->sy_desc == 0) out of this test because coff doesn't have
- those fields, and I can't see when they'd ever be tripped. I
- don't think I understand why they were here so I may have
- introduced a bug. As recently as 1.37 didn't have this test
- anyway. xoxorich. */
-
- if (S_GET_SEGMENT (symbolP) == undefined_section
- && S_GET_VALUE (symbolP) == 0)
+ if (S_GET_SEGMENT (symbolP) == undefined_section)
{
/* The name might be an undefined .global symbol; be sure to
keep the "external" bit. */
#endif
}
- if (S_IS_DEFINED (symbolP))
+ if (S_IS_DEFINED (symbolP) || symbol_equated_p (symbolP))
{
/* Permit register names to be redefined. */
if ((mode != 0 || !S_IS_VOLATILE (symbolP))
/* If the symbol is volatile, copy the symbol and replace the
original with the copy, so that previous uses of the symbol will
retain the value of the symbol at the point of use. */
- else if (S_IS_VOLATILE (symbolP)
- /* This could be avoided when the symbol wasn't used so far, but
- the comment in struc-symbol.h says this flag isn't reliable. */
- && (1 || symbol_used_p (symbolP)))
+ else if (S_IS_VOLATILE (symbolP))
symbolP = symbol_clone (symbolP, 1);
}
const_flag &= ~IN_DEFAULT_SECTION;
#endif
}
+
+/* .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), 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), 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 ();
+}
\f
/* Verify that we are at the end of a line. If not, issue an error and
projects / deliverable / binutils-gdb.git / blobdiff