[RFA] Fix for searching for data symbols

[Daniel Jacobowitz <drow@mvista.com>]

This patch fixes the problem I described in:
	http://sources.redhat.com/ml/gdb/2002-01/msg00223.html

Basically, since we use the bounds of the text segment to search for symbols
in find_pc_*, don't let them return a bogus answer for a symbol we know is
off in data land.

OK to commit, or does anyone prefer a different approach to this?

-- 
Daniel Jacobowitz                           Carnegie Mellon University
MontaVista Software                         Debian GNU/Linux Developer

2002-01-19  Daniel Jacobowitz  <drow@mvista.com>

	* symtab.c (find_pc_sect_psymtab): Do not search psymtabs for
	data symbols, since we search based on textlow and texthigh.
	(find_pc_sect_symtab): Likewise.

Index: symtab.c
===================================================================
RCS file: /cvs/src/src/gdb/symtab.c,v
retrieving revision 1.51
diff -u -p -r1.51 symtab.c
--- symtab.c	2001/12/21 22:32:37	1.51
+++ symtab.c	2002/01/19 17:29:09
@@ -354,12 +354,22 @@ find_pc_sect_psymtab (CORE_ADDR pc, asec
 {
   register struct partial_symtab *pst;
   register struct objfile *objfile;
+  struct minimal_symbol *msymbol;
 
+  /* If we know that this is not a text address, return failure.  */
+  msymbol = lookup_minimal_symbol_by_pc_section (pc, section);
+  if (msymbol
+      && (msymbol->type == mst_data
+	  || msymbol->type == mst_bss
+	  || msymbol->type == mst_abs
+	  || msymbol->type == mst_file_data
+	  || msymbol->type == mst_file_bss))
+    return NULL;
+
   ALL_PSYMTABS (objfile, pst)
   {
     if (pc >= pst->textlow && pc < pst->texthigh)
       {
-	struct minimal_symbol *msymbol;
 	struct partial_symtab *tpst;
 
 	/* An objfile that has its functions reordered might have
@@ -370,7 +380,6 @@ find_pc_sect_psymtab (CORE_ADDR pc, asec
 	    section == 0)	/* can't validate section this way */
 	  return (pst);
 
-	msymbol = lookup_minimal_symbol_by_pc_section (pc, section);
 	if (msymbol == NULL)
 	  return (pst);
 
@@ -1385,6 +1394,17 @@ find_pc_sect_symtab (CORE_ADDR pc, asect
   register struct partial_symtab *ps;
   register struct objfile *objfile;
   CORE_ADDR distance = 0;
+  struct minimal_symbol *msymbol;
+
+  /* If we know that this is not a text address, return failure.  */
+  msymbol = lookup_minimal_symbol_by_pc_section (pc, section);
+  if (msymbol
+      && (msymbol->type == mst_data
+	  || msymbol->type == mst_bss
+	  || msymbol->type == mst_abs
+	  || msymbol->type == mst_file_data
+	  || msymbol->type == mst_file_bss))
+    return NULL;
 
   /* Search all symtabs for the one whose file contains our address, and which
      is the smallest of all the ones containing the address.  This is designed