gold: Provide more failed archive member info in error message

When gold fails to get an archive member, its error message doesn't
have information for

1. The failed archive member name.
2. The cause of failure: non-ELF object vs non-IR object.

This patch adds the failed archive member name and non-ELF/non-IR info
to gold error message.

	* archive.cc (Archive::get_elf_object_for_member): Also print
	archive member and non-ELF/non-IR info on error.

1 files changed, 11 insertions, 2 deletions

diff --git a/gold/archive.cc b/gold/archive.cc
index 4df9e74b07a..fe2a507da7b 100644
--- a/gold/archive.cc
+++ b/gold/archive.cc
@@ -690,6 +690,7 @@ Archive::get_elf_object_for_member(off_t off, bool* punconfigured)
   int read_size;
   Object *obj = NULL;
   bool is_elf_obj = false;
+  bool unclaimed = false;
 
   if (is_elf_object(input_file, memoff, &ehdr, &read_size))
     {
@@ -716,12 +717,20 @@ Archive::get_elf_object_for_member(off_t off, bool* punconfigured)
 	    delete obj;
           return plugin_obj;
         }
+
+      unclaimed = true;
     }
 
   if (!is_elf_obj)
     {
-      gold_error(_("%s: member at %zu is not an ELF object"),
-		 this->name().c_str(), static_cast<size_t>(off));
+      if (unclaimed)
+	gold_error(_("%s: plugin failed to claim member %s at %zu"),
+		   this->name().c_str(), member_name.c_str(),
+		   static_cast<size_t>(off));
+      else
+	gold_error(_("%s: member %s at %zu is not an ELF object"),
+		   this->name().c_str(), member_name.c_str(),
+		   static_cast<size_t>(off));
       return NULL;
     }