as: Replace the removed symbol with the versioned symbol

When a symbol removed by .symver is used in relocation and there is one
and only one versioned symbol, don't remove the symbol.  Instead, mark
it to be removed and replace the removed symbol used in relocation with
the versioned symbol before generating relocation.

	PR gas/28157
	* symbols.c (symbol_flags): Add removed.
	(symbol_entry_find): Updated.
	(symbol_mark_removed): New function.
	(symbol_removed_p): Likewise.
	* symbols.h (symbol_mark_removed): New prototype.
	(symbol_removed_p): Likewise.
	* write.c (write_relocs): Call obj_fixup_removed_symbol on
	removed fixp->fx_addsy and fixp->fx_subsy if defined.
	(set_symtab): Don't add a symbol if symbol_removed_p returns true.
	* config/obj-elf.c (elf_frob_symbol):  Don't remove the symbol
	if it is used on relocation.  Instead, mark it as to be removed
	and issue an error if the symbol has more than one versioned name.
	(elf_fixup_removed_symbol): New function.
	* config/obj-elf.h (elf_fixup_removed_symbol): New prototype.
	(obj_fixup_removed_symbol): New.
	* testsuite/gas/symver/symver11.d: Updated expected error
	message.
	* testsuite/gas/symver/symver16.d: New file.
	* testsuite/gas/symver/symver16.s: Likewise.

1 files changed, 25 insertions, 1 deletions

diff --git a/gas/symbols.c b/gas/symbols.c
index 302eb4b..3cb9425 100644
--- a/gas/symbols.c
+++ b/gas/symbols.c
@@ -78,6 +78,10 @@ struct symbol_flags
      before.  It is cleared as soon as any direct reference to the
      symbol is present.  */
   unsigned int weakrefd : 1;
+
+  /* Whether the symbol has been marked to be removed by a .symver
+     directive.  */
+  unsigned int removed : 1;
 };
 
 /* A pointer in the symbol may point to either a complete symbol
@@ -194,7 +198,7 @@ static void *
 symbol_entry_find (htab_t table, const char *name)
 {
   hashval_t hash = htab_hash_string (name);
-  symbol_entry_t needle = { { { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
+  symbol_entry_t needle = { { { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
 			      hash, name, 0, 0, 0 } };
   return htab_find_with_hash (table, &needle, hash);
 }
@@ -2807,6 +2811,26 @@ symbol_written_p (symbolS *s)
   return s->flags.written;
 }
 
+/* Mark a symbol as to be removed.  */
+
+void
+symbol_mark_removed (symbolS *s)
+{
+  if (s->flags.local_symbol)
+    return;
+  s->flags.removed = 1;
+}
+
+/* Return whether a symbol has been marked to be removed.  */
+
+int
+symbol_removed_p (symbolS *s)
+{
+  if (s->flags.local_symbol)
+    return 0;
+  return s->flags.removed;
+}
+
 /* Mark a symbol has having been resolved.  */
 
 void