diff mbox series

[v4,12/12] RISC-V/bfd: warn about non-power-of-2 stack-align attribute

Message ID 9ab61932-ebdf-4136-bb1f-b9482aa75ea7@suse.com
State New
Headers
Series RISC-V: assorted fixes and (hopefully) improvements |

Checks

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Commit Message

Jan Beulich July 24, 2026, 10:06 a.m. UTC 
  Only power-of-2 values are sensible for alignment. Reject other values.

While there also drop a redundant part of a related conditional.

Reviewed-by: Jiawei jiawei@iscas.ac.cn
---
v4: Add underscore in diagnostic.
v3: New.

Comments

Nelson Chu July 27, 2026, 4:18 a.m. UTC | #1 
LGTM, thanks.

Nelson

On Fri, Jul 24, 2026 at 6:06 PM Jan Beulich <jbeulich@suse.com> wrote:
>
> Only power-of-2 values are sensible for alignment. Reject other values.
>
> While there also drop a redundant part of a related conditional.
>
> Reviewed-by: Jiawei jiawei@iscas.ac.cn
> ---
> v4: Add underscore in diagnostic.
> v3: New.
>
> --- a/bfd/elfxx-riscv.c
> +++ b/bfd/elfxx-riscv.c
> @@ -3906,6 +3906,17 @@ riscv_merge_attributes (bfd *ibfd, struc
>                  ibfd);
>               out_attr[i].i = 1;
>               break;
> +
> +           case Tag_RISCV_stack_align:
> +             if (!(out_attr[i].i & (out_attr[i].i - 1)))
> +               break;
> +
> +             _bfd_error_handler
> +               (_("warning: %pB uses non-power-of-2 `stack_align' attribute; "
> +                  "ignoring"),
> +                ibfd);
> +             out_attr[i].i = 0;
> +             break;
>             }
>         }
>
> @@ -4006,10 +4017,14 @@ riscv_merge_attributes (bfd *ibfd, struc
>         break;
>
>        case Tag_RISCV_stack_align:
> -       if (out_attr[i].i == 0)
> +       if ((in_attr[i].i & (in_attr[i].i - 1)) != 0)
> +         _bfd_error_handler
> +           (_("warning: %pB uses non-power-of-2 `stack_align' attribute; "
> +              "ignoring"),
> +            ibfd);
> +       else if (out_attr[i].i == 0)
>           out_attr[i].i = in_attr[i].i;
>         else if (in_attr[i].i != 0
> -                && out_attr[i].i != 0
>                  && out_attr[i].i != in_attr[i].i)
>           {
>             _bfd_error_handler
>
diff mbox series

Patch

--- a/bfd/elfxx-riscv.c
+++ b/bfd/elfxx-riscv.c
@@ -3906,6 +3906,17 @@  riscv_merge_attributes (bfd *ibfd, struc
 		 ibfd);
 	      out_attr[i].i = 1;
 	      break;
+
+	    case Tag_RISCV_stack_align:
+	      if (!(out_attr[i].i & (out_attr[i].i - 1)))
+		break;
+
+	      _bfd_error_handler
+		(_("warning: %pB uses non-power-of-2 `stack_align' attribute; "
+		   "ignoring"),
+		 ibfd);
+	      out_attr[i].i = 0;
+	      break;
 	    }
 	}
 
@@ -4006,10 +4017,14 @@  riscv_merge_attributes (bfd *ibfd, struc
 	break;
 
       case Tag_RISCV_stack_align:
-	if (out_attr[i].i == 0)
+	if ((in_attr[i].i & (in_attr[i].i - 1)) != 0)
+	  _bfd_error_handler
+	    (_("warning: %pB uses non-power-of-2 `stack_align' attribute; "
+	       "ignoring"),
+	     ibfd);
+	else if (out_attr[i].i == 0)
 	  out_attr[i].i = in_attr[i].i;
 	else if (in_attr[i].i != 0
-		 && out_attr[i].i != 0
 		 && out_attr[i].i != in_attr[i].i)
 	  {
 	    _bfd_error_handler