X-Git-Url: http://drtracing.org/?a=blobdiff_plain;f=gas%2Fread.c;h=5d7a0d2d2254098f47791c8c3c47c1a46675db3d;hb=baee4c9eb00a09d53db7718dbdcb747b8cbafd95;hp=8e4e1bce60d3cabfc229d39c293d9a4f8a900340;hpb=66bd02d33d0451bc127a1166f09f03ea66f273d5;p=deliverable%2Fbinutils-gdb.git

diff --git a/gas/read.c b/gas/read.c
index 8e4e1bce60..5d7a0d2d22 100644
--- a/gas/read.c
+++ b/gas/read.c
@@ -1,6 +1,6 @@
 /* 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.
@@ -38,7 +38,6 @@ Software Foundation, 51 Franklin Street - Fifth Floor, Boston, MA
 #include "sb.h"
 #include "macro.h"
 #include "obstack.h"
-#include "listing.h"
 #include "ecoff.h"
 #include "dw2gencfi.h"
 
@@ -323,6 +322,7 @@ static const pseudo_typeS potable[] = {
 /* endef  */
   {"equ", s_set, 0},
   {"equiv", s_set, 1},
+  {"eqv", s_set, -1},
   {"err", s_err, 0},
   {"error", s_errwarn, 1},
   {"exitm", s_mexit, 0},
@@ -433,6 +433,7 @@ static const pseudo_typeS potable[] = {
   {"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.  */
@@ -441,7 +442,7 @@ static const pseudo_typeS potable[] = {
 static offsetT
 get_absolute_expr (expressionS *exp)
 {
-  expression (exp);
+  expression_and_evaluate (exp);
   if (exp->X_op != O_constant)
     {
       if (exp->X_op != O_absent)
@@ -787,6 +788,14 @@ read_a_source_file (char *name)
 		  /* Input_line_pointer->after ':'.  */
 		  SKIP_WHITESPACE ();
 		}
+              else if (input_line_pointer[1] == '='
+		       && (c == '='
+			   || ((c == ' ' || c == '\t')
+			       && input_line_pointer[2] == '=')))
+		{
+		  equals (s, -1);
+		  demand_empty_rest_of_line ();
+		}
               else if ((c == '='
                        || ((c == ' ' || c == '\t')
                             && input_line_pointer[1] == '='))
@@ -998,10 +1007,14 @@ read_a_source_file (char *name)
 	      unsigned int new_length;
 	      char *tmp_buf = 0;
 
-	      bump_line_counters ();
 	      s = input_line_pointer;
 	      if (strncmp (s, "APP\n", 4))
-		continue;	/* We ignore it */
+		{
+		  /* We ignore it.  */
+		  ignore_rest_of_line ();
+		  continue;
+		}
+	      bump_line_counters ();
 	      s += 4;
 
 	      sb_new (&sbuf);
@@ -1100,7 +1113,7 @@ read_a_source_file (char *name)
 	    continue;
 #endif
 	  input_line_pointer--;
-	  /* Report unknown char as ignored.  */
+	  /* Report unknown char as error.  */
 	  demand_empty_rest_of_line ();
 	}
 
@@ -1269,7 +1282,7 @@ s_align (int arg, int bytes_p)
   unsigned int align_limit = ALIGN_LIMIT;
   unsigned int align;
   char *stop = NULL;
-  char stopc;
+  char stopc = 0;
   offsetT fill = 0;
   int max;
   int fill_p;
@@ -1413,7 +1426,7 @@ s_comm_internal (int param,
   offsetT temp, size;
   symbolS *symbolP = NULL;
   char *stop = NULL;
-  char stopc;
+  char stopc = 0;
   expressionS exp;
 
   if (flag_mri)
@@ -1457,13 +1470,22 @@ s_comm_internal (int param,
 
   *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);
@@ -1480,6 +1502,7 @@ s_comm_internal (int param,
     {
       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;
@@ -1515,7 +1538,7 @@ s_mri_common (int small ATTRIBUTE_UNUSED)
   symbolS *sym;
   offsetT align;
   char *stop = NULL;
-  char stopc;
+  char stopc = 0;
 
   if (!flag_mri)
     {
@@ -1573,6 +1596,7 @@ s_mri_common (int small ATTRIBUTE_UNUSED)
     }
 
   S_SET_EXTERNAL (sym);
+  S_SET_SEGMENT (sym, bfd_com_section_ptr);
   mri_common_symbol = sym;
 
 #ifdef S_SET_ALIGN
@@ -1783,7 +1807,7 @@ s_fail (int ignore ATTRIBUTE_UNUSED)
 {
   offsetT temp;
   char *stop = NULL;
-  char stopc;
+  char stopc = 0;
 
   if (flag_mri)
     stop = mri_comment_field (&stopc);
@@ -1905,7 +1929,7 @@ s_globl (int ignore ATTRIBUTE_UNUSED)
   int c;
   symbolS *symbolP;
   char *stop = NULL;
-  char stopc;
+  char stopc = 0;
 
   if (flag_mri)
     stop = mri_comment_field (&stopc);
@@ -2210,7 +2234,7 @@ s_lsym (int ignore ATTRIBUTE_UNUSED)
     }
 
   input_line_pointer++;
-  expression (&exp);
+  expression_and_evaluate (&exp);
 
   if (exp.X_op != O_constant
       && exp.X_op != O_register)
@@ -2223,15 +2247,7 @@ s_lsym (int ignore ATTRIBUTE_UNUSED)
   *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.  */
@@ -2743,7 +2759,7 @@ end_repeat (int extra)
 }
 
 static void
-assign_symbol (char *name, int no_reassign)
+assign_symbol (char *name, int mode)
 {
   symbolS *symbolP;
 
@@ -2784,18 +2800,34 @@ assign_symbol (char *name, int no_reassign)
 #endif
     }
 
-  /* Permit register names to be redefined.  */
-  if (no_reassign
-      && S_IS_DEFINED (symbolP)
-      && S_GET_SEGMENT (symbolP) != reg_section)
-    as_bad (_("symbol `%s' is already defined"), name);
+  if (S_IS_DEFINED (symbolP) || symbol_equated_p (symbolP))
+    {
+      /* Permit register names to be redefined.  */
+      if ((mode != 0 || !S_IS_VOLATILE (symbolP))
+	  && S_GET_SEGMENT (symbolP) != reg_section)
+	{
+	  as_bad (_("symbol `%s' is already defined"), name);
+	  symbolP = symbol_clone (symbolP, 0);
+	}
+      /* 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))
+	symbolP = symbol_clone (symbolP, 1);
+    }
+
+  if (mode == 0)
+    S_SET_VOLATILE (symbolP);
+  else if (mode < 0)
+    S_SET_FORWARD_REF (symbolP);
 
   pseudo_set (symbolP);
 }
 
-/* Handle the .equ, .equiv and .set directives.  If EQUIV is 1, then
-   this is .equiv, and it is an error if the symbol is already
-   defined.  */
+/* Handle the .equ, .equiv, .eqv, and .set directives.  If EQUIV is 1,
+   then this is .equiv, and it is an error if the symbol is already
+   defined.  If EQUIV is -1, the symbol additionally is a forward
+   reference.  */
 
 void
 s_set (int equiv)
@@ -2846,7 +2878,7 @@ s_space (int mult)
   expressionS val;
   char *p = 0;
   char *stop = NULL;
-  char stopc;
+  char stopc = 0;
   int bytes;
 
 #ifdef md_flush_pending_output
@@ -2917,6 +2949,7 @@ s_space (int mult)
       || val.X_add_number > 0xff
       || (mult != 0 && mult != 1 && val.X_add_number != 0))
     {
+      resolve_expression (&exp);
       if (exp.X_op != O_constant)
 	as_bad (_("unsupported variable size or fill value"));
       else
@@ -2932,6 +2965,9 @@ s_space (int mult)
     }
   else
     {
+      if (now_seg == absolute_section || mri_common_symbol != NULL)
+	resolve_expression (&exp);
+
       if (exp.X_op == O_constant)
 	{
 	  long repeat;
@@ -3018,7 +3054,7 @@ s_float_space (int float_type)
   int flen;
   char temp[MAXIMUM_NUMBER_OF_CHARS_FOR_FLOAT];
   char *stop = NULL;
-  char stopc;
+  char stopc = 0;
 
   if (flag_mri)
     stop = mri_comment_field (&stopc);
@@ -3095,11 +3131,17 @@ void
 s_struct (int ignore ATTRIBUTE_UNUSED)
 {
   char *stop = NULL;
-  char stopc;
+  char stopc = 0;
 
   if (flag_mri)
     stop = mri_comment_field (&stopc);
   abs_section_offset = get_absolute_expression ();
+#if defined (OBJ_ELF) || defined (OBJ_MAYBE_ELF)
+  /* The ELF backend needs to know that we are changing sections, so
+     that .previous works correctly. */
+  if (IS_ELF)
+    obj_elf_section_change_hook ();
+#endif
   subseg_set (absolute_section, 0);
   demand_empty_rest_of_line ();
   if (flag_mri)
@@ -3118,6 +3160,137 @@ s_text (int ignore ATTRIBUTE_UNUSED)
   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 ();
+}
 
 
 /* Verify that we are at the end of a line.  If not, issue an error and
@@ -3185,7 +3358,10 @@ pseudo_set (symbolS *symbolP)
 
   know (symbolP);		/* NULL pointer is logic error.  */
 
-  (void) expression (&exp);
+  if (!S_IS_FORWARD_REF (symbolP))
+    (void) expression (&exp);
+  else
+    (void) deferred_expression (&exp);
 
   if (exp.X_op == O_illegal)
     as_bad (_("illegal expression"));
@@ -3199,6 +3375,7 @@ pseudo_set (symbolS *symbolP)
 	as_bad (_("floating point number invalid"));
     }
   else if (exp.X_op == O_subtract
+	   && !S_IS_FORWARD_REF (symbolP)
 	   && SEG_NORMAL (S_GET_SEGMENT (exp.X_add_symbol))
 	   && (symbol_get_frag (exp.X_add_symbol)
 	       == symbol_get_frag (exp.X_op_symbol)))
@@ -3245,7 +3422,7 @@ pseudo_set (symbolS *symbolP)
 	  *symbol_X_add_number (symbolP) += exp.X_add_number;
 	  break;
 	}
-      else if (seg != undefined_section)
+      else if (!S_IS_FORWARD_REF (symbolP) && seg != undefined_section)
 	{
 	  symbolS *s = exp.X_add_symbol;
 
@@ -3337,7 +3514,7 @@ cons_worker (register int nbytes,	/* 1=.byte, 2=.word, 4=.long.  */
   int c;
   expressionS exp;
   char *stop = NULL;
-  char stopc;
+  char stopc = 0;
 
 #ifdef md_flush_pending_output
   md_flush_pending_output ();
@@ -4833,11 +5010,13 @@ void
 equals (char *sym_name, int reassign)
 {
   char *stop = NULL;
-  char stopc;
+  char stopc = 0;
 
   input_line_pointer++;
   if (*input_line_pointer == '=')
     input_line_pointer++;
+  if (reassign < 0 && *input_line_pointer == '=')
+    input_line_pointer++;
 
   while (*input_line_pointer == ' ' || *input_line_pointer == '\t')
     input_line_pointer++;
@@ -4845,7 +5024,7 @@ equals (char *sym_name, int reassign)
   if (flag_mri)
     stop = mri_comment_field (&stopc);
 
-  assign_symbol (sym_name, !reassign);
+  assign_symbol (sym_name, reassign >= 0 ? !reassign : reassign);
 
   if (flag_mri)
     {