Remove lookup_objfile_from_block

lookup_objfile_from_block mostly duplicates the functionality of
block_objfile, but in a less efficient way.  This patch removes this
function and changes the callers to use block_objfile instead.

Tested by the buildbot.

gdb/ChangeLog
2020-05-15  Tom Tromey  <tom@tromey.com>

	* symtab.c (lookup_language_this, lookup_symbol_aux): Use
	block_objfile.
	(lookup_objfile_from_block): Remove.
	(lookup_symbol_in_block, lookup_symbol_in_static_block)
	(lookup_global_symbol): Use block_objfile.
	* symtab.h (lookup_objfile_from_block): Don't declare.
	* printcmd.c (clear_dangling_display_expressions): Use
	block_objfile.
	* parse.c (operator_check_standard): Use block_objfile.

1 files changed, 13 insertions, 5 deletions

diff --git a/gdb/printcmd.c b/gdb/printcmd.c
index c94ad0a..388a0b2 100644
--- a/gdb/printcmd.c
+++ b/gdb/printcmd.c
@@ -2128,12 +2128,20 @@ clear_dangling_display_expressions (struct objfile *objfile)
       if (d->pspace != pspace)
 	continue;
 
-      if (lookup_objfile_from_block (d->block) == objfile
+      struct objfile *bl_objf = nullptr;
+      if (d->block != nullptr)
+	{
+	  bl_objf = block_objfile (d->block);
+	  if (bl_objf->separate_debug_objfile_backlink != nullptr)
+	    bl_objf = bl_objf->separate_debug_objfile_backlink;
+	}
+
+      if (bl_objf == objfile
 	  || (d->exp != NULL && exp_uses_objfile (d->exp.get (), objfile)))
-      {
-	d->exp.reset ();
-	d->block = NULL;
-      }
+	{
+	  d->exp.reset ();
+	  d->block = NULL;
+	}
     }
 }