* dbxread.c (process_one_symbol): Handle N_FUN symbols

	for Sun acc 3.0 under SunOS4.

	Changes to improve handling of runtime common symbols
	under SunOS4.
	* minsyms.c (get_symbol_leading_char):  New routine to determine
	the leading symbol character for an objfile.
	(prim_record_minimal_symbol_and_info, install_minimal_symbols):
	Use it.
	* objfiles.h (rt_common_objfile):  New global, points to objfile
	containing the runtime common minimal symbols.
	* objfiles.c (free_objfile):  Mark rt_common_objfile as
	unallocated before freeing it.
	* solib.c (allocate_rt_common_objfile):  New routine to allocate
	an objfile for the runtime common minimal symbols.
	(solib_add_common_symbols):  Allocate an objfile for the runtime
	common symbols if necessary and put common symbols into it.
	Clean up code and comments.
	(solib_add, special_symbol_handling):  Cleanup comments regarding
	runtime common symbols.
	* stabsread.c (scan_file_globals_1):  New routine, contains
	old scan_file_globals code. Checks if there are any unresolved
	global symbols before starting the expensive minimal symbol table
	search.
	(scan_file_globals):  Now calls scan_file_globals_1 for the passed
	objfile and eventually for the runtime common objfile. Complains
	about any unresolved global symbols and removes them from the
	global symbol chain to avoid dangling pointers into the symbol
	table if the symbol table is reread.

5 files changed, 124 insertions, 12 deletions

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index c7cd97b..e300be6 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,35 @@
+Sat Jan  7 07:23:53 1995  Peter Schauer  (pes@regent.e-technik.tu-muenchen.de)
+
+	* dbxread.c (process_one_symbol):  Handle N_FUN symbols
+	for Sun acc 3.0 under SunOS4.
+
+	Changes to improve handling of runtime common symbols
+	under SunOS4.
+	* minsyms.c (get_symbol_leading_char):  New routine to determine
+	the leading symbol character for an objfile.
+	(prim_record_minimal_symbol_and_info, install_minimal_symbols):
+	Use it.
+	* objfiles.h (rt_common_objfile):  New global, points to objfile
+	containing the runtime common minimal symbols.
+	* objfiles.c (free_objfile):  Mark rt_common_objfile as
+	unallocated before freeing it.
+	* solib.c (allocate_rt_common_objfile):  New routine to allocate
+	an objfile for the runtime common minimal symbols.
+	(solib_add_common_symbols):  Allocate an objfile for the runtime
+	common symbols if necessary and put common symbols into it.
+	Clean up code and comments.
+	(solib_add, special_symbol_handling):  Cleanup comments regarding
+	runtime common symbols.
+	* stabsread.c (scan_file_globals_1):  New routine, contains
+	old scan_file_globals code. Checks if there are any unresolved
+	global symbols before starting the expensive minimal symbol table
+	search.
+	(scan_file_globals):  Now calls scan_file_globals_1 for the passed
+	objfile and eventually for the runtime common objfile. Complains
+	about any unresolved global symbols and removes them from the
+	global symbol chain to avoid dangling pointers into the symbol
+	table if the symbol table is reread.
+
 Thu Jan  5 17:38:29 1995  Stu Grossman  (grossman@cygnus.com)
 
 	* Makefile.in (install_only uninstall):  Indent for clarity.
diff --git a/gdb/minsyms.c b/gdb/minsyms.c
index 77d7466..26777f8 100644
--- a/gdb/minsyms.c
+++ b/gdb/minsyms.c
@@ -1,5 +1,5 @@
 /* GDB routines for manipulating the minimal symbol tables.
-   Copyright 1992, 1993, 1994 Free Software Foundation, Inc.
+   Copyright 1992, 1993, 1994, 1995 Free Software Foundation, Inc.
    Contributed by Cygnus Support, using pieces from other GDB modules.
 
 This file is part of GDB.
@@ -260,6 +260,22 @@ lookup_minimal_symbol_by_pc (pc)
   return (best_symbol);
 }
 
+/* Return leading symbol character for a BFD. If BFD is NULL,
+   return the leading symbol character from the main objfile.  */
+
+static int get_symbol_leading_char PARAMS ((bfd *));
+
+static int
+get_symbol_leading_char (abfd)
+     bfd * abfd;
+{
+  if (abfd != NULL)
+    return bfd_get_symbol_leading_char (abfd);
+  if (symfile_objfile != NULL && symfile_objfile->obfd != NULL)
+    return bfd_get_symbol_leading_char (symfile_objfile->obfd);
+  return 0;
+}
+
 /* Prepare to start collecting minimal symbols.  Note that presetting
    msym_bunch_index to BUNCH_SIZE causes the first call to save a minimal
    symbol to allocate the memory for the first bunch. */
@@ -331,7 +347,7 @@ prim_record_minimal_symbol_and_info (name, address, ms_type, info, section,
 
       {
 	const char *tempstring = name;
-	if (tempstring[0] == bfd_get_symbol_leading_char (objfile->obfd))
+	if (tempstring[0] == get_symbol_leading_char (objfile->obfd))
 	  ++tempstring;
 	if (STREQN (tempstring, "__gnu_compiled", 14))
 	  return;
@@ -539,7 +555,7 @@ install_minimal_symbols (objfile)
 	 each bunch is full. */
       
       mcount = objfile->minimal_symbol_count;
-      leading_char = bfd_get_symbol_leading_char (objfile->obfd);
+      leading_char = get_symbol_leading_char (objfile->obfd);
       
       for (bunch = msym_bunch; bunch != NULL; bunch = bunch -> next)
 	{
diff --git a/gdb/objfiles.c b/gdb/objfiles.c
index 891531d..cce17f8 100644
--- a/gdb/objfiles.c
+++ b/gdb/objfiles.c
@@ -1,5 +1,5 @@
 /* GDB routines for manipulating objfiles.
-   Copyright 1992 Free Software Foundation, Inc.
+   Copyright 1992, 1993, 1994, 1995 Free Software Foundation, Inc.
    Contributed by Cygnus Support, using pieces from other GDB modules.
 
 This file is part of GDB.
@@ -59,6 +59,7 @@ extern char *error_pre_print;
 struct objfile *object_files;		/* Linked list of all objfiles */
 struct objfile *current_objfile;	/* For symbol file being read in */
 struct objfile *symfile_objfile;	/* Main symbol table loaded from */
+struct objfile *rt_common_objfile;	/* For runtime common symbols */
 
 int mapped_symbol_files;		/* Try to use mapped symbol files */
 
@@ -372,6 +373,12 @@ free_objfile (objfile)
 
   unlink_objfile (objfile);
 
+  /* If we are going to free the runtime common objfile, mark it
+     as unallocated.  */
+
+  if (objfile == rt_common_objfile)
+    rt_common_objfile = NULL;
+
   /* Before the symbol table code was redone to make it easier to
      selectively load and remove information particular to a specific
      linkage unit, gdb used to do these things whenever the monolithic
diff --git a/gdb/objfiles.h b/gdb/objfiles.h
index 0a69f20..a4a1404 100644
--- a/gdb/objfiles.h
+++ b/gdb/objfiles.h
@@ -1,5 +1,5 @@
 /* Definitions for symbol file management in GDB.
-   Copyright (C) 1992, 1993, 1994 Free Software Foundation, Inc.
+   Copyright (C) 1992, 1993, 1994, 1995 Free Software Foundation, Inc.
 
 This file is part of GDB.
 
@@ -208,8 +208,8 @@ struct objfile
 
   struct partial_symtab *free_psymtabs;
 
-  /* The object file's BFD.  Can be null, in which case bfd_open (name) and
-     put the result here.  */
+  /* The object file's BFD.  Can be null if the objfile contains only
+     minimal symbols, e.g. the run time common symbols for SunOS4.  */
 
   bfd *obfd;
 
@@ -356,6 +356,11 @@ struct objfile
 
 extern struct objfile *symfile_objfile;
 
+/* The object file that contains the runtime common minimal symbols
+   for SunOS4. Note that this objfile has no associated BFD.  */
+
+extern struct objfile *rt_common_objfile;
+
 /* When we need to allocate a new type, we need to know which type_obstack
    to allocate the type on, since there is one for each objfile.  The places
    where types are allocated are deeply buried in function call hierarchies
diff --git a/gdb/stabsread.c b/gdb/stabsread.c
index a21e521..8bc9948 100644
--- a/gdb/stabsread.c
+++ b/gdb/stabsread.c
@@ -1,5 +1,5 @@
 /* Support routines for decoding "stabs" debugging information format.
-   Copyright 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994
+   Copyright 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995
              Free Software Foundation, Inc.
 
 This file is part of GDB.
@@ -186,6 +186,9 @@ struct complaint unrecognized_cplus_name_complaint =
 struct complaint rs6000_builtin_complaint =
   {"Unknown builtin type %d", 0, 0};
 
+struct complaint unresolved_sym_chain_complaint =
+  {"%s: `%s' from global_sym_chain unresolved", 0, 0};
+
 struct complaint stabs_general_complaint =
   {"%s", 0, 0};
 
@@ -3801,18 +3804,31 @@ GDB internal error.  cleanup_undefined_types with bad type %d.", 0, 0};
 
 /* Scan through all of the global symbols defined in the object file,
    assigning values to the debugging symbols that need to be assigned
-   to.  Get these symbols from the minimal symbol table.  */
+   to.  Get these symbols from the minimal symbol table.
+   Return 1 if there might still be unresolved debugging symbols, else 0.  */
 
-void
-scan_file_globals (objfile)
+static int scan_file_globals_1 PARAMS ((struct objfile *));
+
+static int
+scan_file_globals_1 (objfile)
      struct objfile *objfile;
 {
   int hash;
   struct minimal_symbol *msymbol;
   struct symbol *sym, *prev;
 
+  /* Avoid expensive loop through all minimal symbols if there are
+     no unresolved symbols.  */
+  for (hash = 0; hash < HASHSIZE; hash++)
+    {
+      if (global_sym_chain[hash])
+	break;
+    }
+  if (hash >= HASHSIZE)
+    return 0;
+
   if (objfile->msymbols == 0)		/* Beware the null file.  */
-    return;
+    return 1;
 
   for (msymbol = objfile -> msymbols; SYMBOL_NAME (msymbol) != NULL; msymbol++)
     {
@@ -3883,6 +3899,42 @@ scan_file_globals (objfile)
 	    }
 	}
     }
+  return 1;
+}
+
+/* Assign values to global debugging symbols.
+   Search the passed objfile first, then try the runtime common symbols.
+   Complain about any remaining unresolved symbols and remove them
+   from the chain.  */
+
+void
+scan_file_globals (objfile)
+     struct objfile *objfile;
+{
+  int hash;
+  struct symbol *sym, *prev;
+
+  if (scan_file_globals_1 (objfile) == 0)
+    return;
+  if (rt_common_objfile && scan_file_globals_1 (rt_common_objfile) == 0)
+    return;
+
+  for (hash = 0; hash < HASHSIZE; hash++)
+    {
+      sym = global_sym_chain[hash];
+      while (sym)
+	{
+	  complain (&unresolved_sym_chain_complaint,
+		    objfile->name, SYMBOL_NAME (sym));
+
+	  /* Change the symbol address from the misleading chain value
+	     to address zero.  */
+	  prev = sym;
+	  sym = SYMBOL_VALUE_CHAIN (sym);
+	  SYMBOL_VALUE_ADDRESS (prev) = 0;
+	}
+    }
+  memset (global_sym_chain, 0, sizeof (global_sym_chain));
 }
 
 /* Initialize anything that needs initializing when starting to read