[RFA 10/15] Introduce objfile::reset_psymtabs

[Tom Tromey <tom@tromey.com>]

This introduces a new method, objfile::reset_psymtabs, and changes
reread_symbols to use it.  This method simply destroys the existing
partial symbols and recreates the psymtab_storage object.

This patch fixes a latent bug -- namely, that reread_symbols should
clear objfile::psymbol_map, but does not.  I can submit that
separately if you'd prefer.

gdb/ChangeLog
2018-05-09  Tom Tromey  <tom@tromey.com>

	* symfile.c (reread_symbols): Call objfile->reset_psymtabs.
	* objfiles.h (objfile::reset_psymtabs): New method.
---
 gdb/ChangeLog  |  5 +++++
 gdb/objfiles.h | 10 ++++++++++
 gdb/symfile.c  | 13 +------------
 3 files changed, 16 insertions(+), 12 deletions(-)

diff --git a/gdb/objfiles.h b/gdb/objfiles.h
index a49954df60..fd4266d6bf 100644
--- a/gdb/objfiles.h
+++ b/gdb/objfiles.h
@@ -292,6 +292,16 @@ struct objfile
 
   DISABLE_COPY_AND_ASSIGN (objfile);
 
+  /* Reset the storage for the partial symbol tables.  */
+
+  void reset_psymtabs ()
+  {
+    psymbol_map.clear ();
+    psymtab_map.clear ();
+    partial_symtabs.reset (new psymtab_storage (this));
+  }
+
+
   /* All struct objfile's are chained together by their next pointers.
      The program space field "objfiles"  (frequently referenced via
      the macro "object_files") points to the first link in this chain.  */
diff --git a/gdb/symfile.c b/gdb/symfile.c
index a23c051c3e..98b063ed02 100644
--- a/gdb/symfile.c
+++ b/gdb/symfile.c
@@ -2395,24 +2395,13 @@ reread_symbols (void)
 	  memcpy (offsets, objfile->section_offsets,
 		  SIZEOF_N_SECTION_OFFSETS (num_offsets));
 
-	  /* FIXME: Do we have to free a whole linked list, or is this
-	     enough?  */
-	  objfile->partial_symtabs->global_psymbols.clear ();
-	  objfile->partial_symtabs->static_psymbols.clear ();
-	  objfile->psymtab_map.clear ();
-
-	  /* Free the obstacks for non-reusable objfiles.  */
-	  psymbol_bcache_free (objfile->partial_symtabs->psymbol_cache);
-	  objfile->partial_symtabs->psymbol_cache = psymbol_bcache_init ();
+	  objfile->reset_psymtabs ();
 
 	  /* NB: after this call to obstack_free, objfiles_changed
 	     will need to be called (see discussion below).  */
 	  obstack_free (&objfile->objfile_obstack, 0);
 	  objfile->sections = NULL;
 	  objfile->compunit_symtabs = NULL;
-	  objfile->partial_symtabs->psymtabs = NULL;
-	  objfile->partial_symtabs->psymtabs_addrmap = NULL;
-	  objfile->partial_symtabs->free_psymtabs = NULL;
 	  objfile->template_symbols = NULL;
 
 	  /* obstack_init also initializes the obstack so it is
-- 
2.13.6