From 0e931cf0eed83e9af7fe3eaf10de174d98c93bc0 Mon Sep 17 00:00:00 2001
From: Joel Brobecker <brobecker@gnat.com>
Date: Mon, 22 Apr 2002 10:19:35 +0000
Subject: [PATCH]         * symfile.h (get_section_index): Define.         *
 symfile.c (get_section_index): New function.         * mdebugread.c
 (SC_IS_SBSS): New macro.         (SC_IS_BSS): Return true for the scBss
 storage class only, as         the scSBss storage class refers to the .sbss
 section.         (parse_partial_symbols): Discard the symbols which
 associated         section does not exist.         Make sure to use the .sbss
 section index for symbols which         storage class is scBss, rather than
 using the .bss section index.

---
 gdb/mdebugread.c | 49 +++++++++++++++++++++++++++++++++++++++++++++++-
 gdb/symfile.c    | 14 ++++++++++++++
 2 files changed, 62 insertions(+), 1 deletion(-)

diff --git a/gdb/mdebugread.c b/gdb/mdebugread.c
index 1bc9eef786..c974c9e874 100644
--- a/gdb/mdebugread.c
+++ b/gdb/mdebugread.c
@@ -143,7 +143,8 @@ struct symloc
 		   || (sc) == scPData \
 		   || (sc) == scXData)
 #define SC_IS_COMMON(sc) ((sc) == scCommon || (sc) == scSCommon)
-#define SC_IS_BSS(sc) ((sc) == scBss || (sc) == scSBss)
+#define SC_IS_BSS(sc) ((sc) == scBss)
+#define SC_IS_SBSS(sc) ((sc) == scSBss)
 #define SC_IS_UNDEF(sc) ((sc) == scUndefined || (sc) == scSUndefined)
 
 /* Various complaints about symbol reading that don't abort the process */
@@ -2425,26 +2426,72 @@ parse_partial_symbols (struct objfile *objfile)
 	      ms_type = mst_bss;
 	      svalue += ANOFFSET (objfile->section_offsets, SECT_OFF_BSS (objfile));
 	    }
+          else if (SC_IS_SBSS (ext_in->asym.sc))
+            {
+              ms_type = mst_bss;
+              svalue += ANOFFSET (objfile->section_offsets, 
+                                  get_section_index (objfile, ".sbss"));
+            }
 	  else
 	    ms_type = mst_abs;
 	  break;
 	case stLabel:
 	  /* Label */
+
+          /* On certain platforms, some extra label symbols can be
+             generated by the linker. One possible usage for this kind
+             of symbols is to represent the address of the begining of a
+             given section. For instance, on Tru64 5.1, the address of
+             the _ftext label is the start address of the .text section.
+
+             The storage class of these symbols is usually directly
+             related to the section to which the symbol refers. For
+             instance, on Tru64 5.1, the storage class for the _fdata
+             label is scData, refering to the .data section.
+
+             It is actually possible that the section associated to the
+             storage class of the label does not exist. On True64 5.1
+             for instance, the libm.so shared library does not contain
+             any .data section, although it contains a _fpdata label
+             which storage class is scData... Since these symbols are
+             usually useless for the debugger user anyway, we just
+             discard these symbols.
+           */
+          
 	  if (SC_IS_TEXT (ext_in->asym.sc))
 	    {
+              if (objfile->sect_index_text == -1)
+                continue;
+                
 	      ms_type = mst_file_text;
 	      svalue += ANOFFSET (objfile->section_offsets, SECT_OFF_TEXT (objfile));
 	    }
 	  else if (SC_IS_DATA (ext_in->asym.sc))
 	    {
+              if (objfile->sect_index_data == -1)
+                continue;
+
 	      ms_type = mst_file_data;
 	      svalue += ANOFFSET (objfile->section_offsets, SECT_OFF_DATA (objfile));
 	    }
 	  else if (SC_IS_BSS (ext_in->asym.sc))
 	    {
+              if (objfile->sect_index_bss == -1)
+                continue;
+
 	      ms_type = mst_file_bss;
 	      svalue += ANOFFSET (objfile->section_offsets, SECT_OFF_BSS (objfile));
 	    }
+          else if (SC_IS_SBSS (ext_in->asym.sc))
+            {
+              const int sbss_sect_index = get_section_index (objfile, ".sbss");
+
+              if (sbss_sect_index == -1)
+                continue;
+
+              ms_type = mst_file_bss;
+              svalue += ANOFFSET (objfile->section_offsets, sbss_sect_index);
+            }
 	  else
 	    ms_type = mst_abs;
 	  break;
diff --git a/gdb/symfile.c b/gdb/symfile.c
index d2d4e620e4..2671770d17 100644
--- a/gdb/symfile.c
+++ b/gdb/symfile.c
@@ -120,6 +120,8 @@ static void cashier_psymtab (struct partial_symtab *);
 
 bfd *symfile_bfd_open (char *);
 
+int get_section_index (struct objfile *, char *);
+
 static void find_sym_fns (struct objfile *);
 
 static void decrement_reading_symtab (void *);
@@ -1115,6 +1117,18 @@ symfile_bfd_open (char *name)
   return (sym_bfd);
 }
 
+/* Return the section index for the given section name. Return -1 if
+   the section was not found. */
+int
+get_section_index (struct objfile *objfile, char *section_name)
+{
+  asection *sect = bfd_get_section_by_name (objfile->obfd, section_name);
+  if (sect)
+    return sect->index;
+  else
+    return -1;
+}
+
 /* Link a new symtab_fns into the global symtab_fns list.  Called on gdb
    startup by the _initialize routine in each object file format reader,
    to register information about each format the the reader is prepared