Check unsupported .symver with common symbol

The .symver directive on common symbol creates a new common symbol,
which shouldn't be allowed, similar to alias on common symbol:

$ cat y.S
	.comm	bar,8,8
	 .set bar1,bar
$ as -o y.o y.S
y.S: Assembler messages:
y.S:2: Error: `bar1' can't be equated to common symbol 'bar'
$

	PR gas/21661
	* config/obj-elf.c (obj_elf_symver): Don't allow .symver with
	common symbol.
	(elf_frob_symbol): Likewise.
	* testsuite/gas/elf/elf.exp: Run pr21661.
	* testsuite/gas/elf/pr21661.d: New file.
	* testsuite/gas/elf/pr21661.s: Likewise.

1 files changed, 15 insertions, 0 deletions

diff --git a/gas/config/obj-elf.c b/gas/config/obj-elf.c
index 3696d5e..49d99a4 100644
--- a/gas/config/obj-elf.c
+++ b/gas/config/obj-elf.c
@@ -1414,6 +1414,14 @@ obj_elf_symver (int ignore ATTRIBUTE_UNUSED)
   c = get_symbol_name (& name);
   lex_type[(unsigned char) '@'] = old_lexat;
 
+  if (S_IS_COMMON (sym))
+    {
+      as_bad (_("`%s' can't be versioned to common symbol '%s'"),
+	      name, S_GET_NAME (sym));
+      ignore_rest_of_line ();
+      return;
+    }
+
   if (symbol_get_obj (sym)->versioned_name == NULL)
     {
       symbol_get_obj (sym)->versioned_name = xstrdup (name);
@@ -2277,6 +2285,13 @@ elf_frob_symbol (symbolS *symp, int *puntp)
 	      symp2 = symbol_find_or_make (sy_obj->versioned_name);
 
 	      /* Now we act as though we saw symp2 = sym.  */
+	      if (S_IS_COMMON (symp))
+		{
+		  as_bad (_("`%s' can't be versioned to common symbol '%s'"),
+			  sy_obj->versioned_name, S_GET_NAME (symp));
+		  *puntp = TRUE;
+		  return;
+		}
 
 	      S_SET_SEGMENT (symp2, S_GET_SEGMENT (symp));