o Fix code deleting psymtab entry from objfile's list.

	Only worked if the first element in the list was
	being deleted.
o	When MAINLINE (reading main objectfile and need to
	clear out old data), change elfread.c so that the
	psymbol table is emptied once (in elf_symfile_read)
	instead of multiple times in each *_read_psymtab
	function.
o	For elf_symfile_read, load dwarf2 symbols last
	(so that they are searched for first).
o	In mdebug_psymtab_read, delete check to see if
	symbols for current source file already loaded.
	Test doesn't work for .h files.  Above change
	works better

6 files changed, 75 insertions, 70 deletions

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 0dceb05..c5660fc 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,30 @@
+Thu Dec 18 00:26:46 1997  Andrew Cagney  <cagney@b1.cygnus.com>
+
+	* mdebugread.c (parse_partial_symbols): Delete check that symbols
+ 	for file not already loaded.  Did not work when an include file
+ 	was involved.
+
+Wed Dec 17 10:43:04 1997  Andrew Cagney  <cagney@b1.cygnus.com>
+
+	* elfread.c (elf_symfile_read): Since the partial symbol table is
+ 	searched last in first, insert mdebug or XCOFF info into the
+ 	partial symbol table before any DWARF2 info.
+
+Thu Dec 18 00:00:48 1997  Andrew Cagney  <cagney@b1.cygnus.com>
+
+	* symfile.c (init_psymbol_list): Handle init with zero elements.
+
+	* elfread.c (elf_symfile_read): If `mainline', clear psymbol table
+ 	using init_psymbol_list 0.  For build_psymtabs functions, pass
+ 	mainline==0 so that psymbol_list isn't re-initialized.
+
+	* symfile.c (discard_psymtab): New function, correctly unlink an
+ 	empty psymtab from an object file.
+	* dbxread.c (end_psymtab): Call discard_psymtab.
+	* xcoffread.c (xcoff_end_psymtab): Ditto.
+	* hpread.c (hpread_end_psymtab):  Ditto.
+	* os9kread.c (os9k_end_psymtab):  Ditto.
+
 Wed Dec 17 10:47:05 1997  Michael Snyder  (msnyder@cleaver.cygnus.com)
 
 	* tracepoint.c (set_raw_tracepoint): initialize addr_string
diff --git a/gdb/elfread.c b/gdb/elfread.c
index d698be7..179a0ef 100644
--- a/gdb/elfread.c
+++ b/gdb/elfread.c
@@ -615,21 +615,42 @@ elf_symfile_read (objfile, section_offsets, mainline)
   elf_symtab_read (abfd, offset, objfile, 1);
 
   /* Now process debugging information, which is contained in
-     special ELF sections.  We first have to find them... */
+     special ELF sections. */
 
-  bfd_map_over_sections (abfd, elf_locate_sections, (PTR) &ei);
-  if (dwarf2_has_info (abfd))
+  /* If we are reinitializing, or if we have never loaded syms yet,
+     set table to empty.  MAINLINE is cleared so that *_read_psymtab
+     functions do not all also re-initialize the psymbol table. */
+  if (mainline)
     {
-      /* DWARF 2 sections */
-      dwarf2_build_psymtabs (objfile, section_offsets, mainline);
+      init_psymbol_list (objfile, 0);
+      mainline = 0;
     }
-  else if (ei.dboffset && ei.lnoffset)
+
+  /* We first have to find them... */
+  bfd_map_over_sections (abfd, elf_locate_sections, (PTR) &ei);
+
+  /* ELF debugging information is inserted into the psymtab in the
+     order of least informative first - most informative last.  Since
+     the psymtab table is searched `most recent insertion first' this
+     increases the probability that more detailed debug information
+     for a section is found.
+
+     For instance, an object file might contain both .mdebug (XCOFF)
+     and .debug_info (DWARF2) sections then .mdebug is inserted first
+     (searched last) and DWARF2 is inserted last (searched first).  If
+     we don't do this then the XCOFF info is found first - for code in
+     an included file XCOFF info is useless. */
+
+  if (ei.mdebugsect)
     {
-      /* DWARF sections */
-      dwarf_build_psymtabs (objfile,
-			    section_offsets, mainline,
-			    ei.dboffset, ei.dbsize,
-			    ei.lnoffset, ei.lnsize);
+      const struct ecoff_debug_swap *swap;
+
+      /* .mdebug section, presumably holding ECOFF debugging
+	 information.  */
+      swap = get_elf_backend_data (abfd)->elf_backend_ecoff_debug_swap;
+      if (swap)
+	elfmdebug_build_psymtabs (objfile, swap, ei.mdebugsect,
+				  section_offsets);
     }
   if (ei.stabsect)
     {
@@ -649,16 +670,18 @@ elf_symfile_read (objfile, section_offsets, mainline)
 				str_sect->filepos,
 				bfd_section_size (abfd, str_sect));
     }
-  if (ei.mdebugsect)
+  if (dwarf2_has_info (abfd))
     {
-      const struct ecoff_debug_swap *swap;
-
-      /* .mdebug section, presumably holding ECOFF debugging
-	 information.  */
-      swap = get_elf_backend_data (abfd)->elf_backend_ecoff_debug_swap;
-      if (swap)
-	elfmdebug_build_psymtabs (objfile, swap, ei.mdebugsect,
-				  section_offsets);
+      /* DWARF 2 sections */
+      dwarf2_build_psymtabs (objfile, section_offsets, mainline);
+    }
+  else if (ei.dboffset && ei.lnoffset)
+    {
+      /* DWARF sections */
+      dwarf_build_psymtabs (objfile,
+			    section_offsets, mainline,
+			    ei.dboffset, ei.dbsize,
+			    ei.lnoffset, ei.lnsize);
     }
 
   /* Install any minimal symbols that have been collected as the current
diff --git a/gdb/hpread.c b/gdb/hpread.c
index 8183558..0e41746 100644
--- a/gdb/hpread.c
+++ b/gdb/hpread.c
@@ -938,21 +938,8 @@ hpread_end_psymtab (pst, include_list, num_includes, capping_symbol_offset,
 	 is wrong, in that a psymtab with N_SLINE entries but nothing else
 	 is not empty, but we don't realize that.  Fixing that without slowing
 	 things down might be tricky.  */
-      struct partial_symtab *prev_pst;
 
-      /* First, snip it out of the psymtab chain */
-
-      if (pst->objfile->psymtabs == pst)
-	pst->objfile->psymtabs = pst->next;
-      else
-	for (prev_pst = pst->objfile->psymtabs; prev_pst; prev_pst = pst->next)
-	  if (prev_pst->next == pst)
-	    prev_pst->next = pst->next;
-
-      /* Next, put it on a free list for recycling */
-
-      pst->next = pst->objfile->free_psymtabs;
-      pst->objfile->free_psymtabs = pst;
+      discard_psymtab (pst);
 
       /* Indicate that psymtab was thrown away.  */
       pst = (struct partial_symtab *)NULL;
diff --git a/gdb/mdebugread.c b/gdb/mdebugread.c
index f3f3ec4..807c36f 100644
--- a/gdb/mdebugread.c
+++ b/gdb/mdebugread.c
@@ -2490,13 +2490,6 @@ parse_partial_symbols (objfile, section_offsets)
 
       cur_fdr = fh = debug_info->fdr + f_idx;
 
-      /* If a partial symbol table has already been read for this file,
-         don't make another one.  This works around a problem with some
-	 compilers that emit both DWARF and mdebug sections for a single
-	 module.  */
-      if (lookup_partial_symtab (fdr_name (fh)))
-	continue;
-
       if (fh->csym == 0)
 	{
 	  fdr_to_pst[f_idx].pst = NULL;
diff --git a/gdb/os9kread.c b/gdb/os9kread.c
index 4370653..e143090 100644
--- a/gdb/os9kread.c
+++ b/gdb/os9kread.c
@@ -1003,7 +1003,7 @@ os9k_end_psymtab (pst, include_list, num_includes, capping_symbol_cnt,
      CORE_ADDR capping_text;
      struct partial_symtab **dependency_list;
      int number_dependencies;
-/*     struct partial_symbol *capping_global, *capping_static;*/
+     /* struct partial_symbol *capping_global, *capping_static; */
 {
   int i;
   struct partial_symtab *p1;
@@ -1160,22 +1160,10 @@ os9k_end_psymtab (pst, include_list, num_includes, capping_symbol_cnt,
    && pst->n_static_syms == 0) {
     /* Throw away this psymtab, it's empty.  We can't deallocate it, since
        it is on the obstack, but we can forget to chain it on the list.  */
-    struct partial_symtab *prev_pst;
-
-    /* First, snip it out of the psymtab chain */
-
-    if (pst->objfile->psymtabs == pst)
-      pst->objfile->psymtabs = pst->next;
-    else
-      for (prev_pst = pst->objfile->psymtabs; prev_pst; prev_pst = pst->next)
-	if (prev_pst->next == pst)
-	  prev_pst->next = pst->next;
+    /* Indicate that psymtab was thrown away.  */
 
-    /* Next, put it on a free list for recycling */
-    pst->next = pst->objfile->free_psymtabs;
-    pst->objfile->free_psymtabs = pst;
+    discard_psymtab (pst);
 
-    /* Indicate that psymtab was thrown away.  */
     pst = (struct partial_symtab *)NULL;
   }
   return pst;
diff --git a/gdb/xcoffread.c b/gdb/xcoffread.c
index 956f576..dc34f32 100644
--- a/gdb/xcoffread.c
+++ b/gdb/xcoffread.c
@@ -2115,21 +2115,8 @@ xcoff_end_psymtab (pst, include_list, num_includes, capping_symbol_number,
 	 it is on the obstack, but we can forget to chain it on the list.  */
       /* Empty psymtabs happen as a result of header files which don't have
 	 any symbols in them.  There can be a lot of them.  */
-      struct partial_symtab *prev_pst;
 
-      /* First, snip it out of the psymtab chain */
-
-      if (pst->objfile->psymtabs == pst)
-	pst->objfile->psymtabs = pst->next;
-      else
-	for (prev_pst = pst->objfile->psymtabs; prev_pst; prev_pst = pst->next)
-	  if (prev_pst->next == pst)
-	    prev_pst->next = pst->next;
-
-      /* Next, put it on a free list for recycling */
-
-      pst->next = pst->objfile->free_psymtabs;
-      pst->objfile->free_psymtabs = pst;
+      discard_psymtab (pst);
 
       /* Indicate that psymtab was thrown away.  */
       pst = (struct partial_symtab *)NULL;