[PATCH] ARC: Explicitly specify OUTPUT_FORMAT in the linker script

[PATCH] ARC: Explicitly specify OUTPUT_FORMAT in the linker script

[Alexey Brodkin]

It might be a good idea to explicitly specify BFD format
depending on -EB/-EL option passed to the linker and not rely on
default behavior as we have now.

Description of the OUTPUT_FORMAT command is available here:
https://sourceware.org/binutils/docs/ld/Format-Commands.html#Format-Commands

Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Cc: Cupertino Miranda <cmiranda@synopsys.com>
Cc: Claudiu Zissulescu <claziss@synopsys.com>
---
 arch/arc/kernel/vmlinux.lds.S | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/arc/kernel/vmlinux.lds.S b/arch/arc/kernel/vmlinux.lds.S
index f35ed578e007..0a1affc56d76 100644
--- a/arch/arc/kernel/vmlinux.lds.S
+++ b/arch/arc/kernel/vmlinux.lds.S
@@ -11,6 +11,7 @@
 #include <asm/page.h>
 #include <asm/thread_info.h>
 
+OUTPUT_FORMAT("elf32-littlearc", "elf32-bigarc", "elf32-littlearc")
 OUTPUT_ARCH(arc)
 ENTRY(res_service)
 
-- 
2.16.2

Re: [PATCH] ARC: Explicitly specify OUTPUT_FORMAT in the linker script

[Vineet Gupta]

On 06/01/2018 03:49 AM, Alexey Brodkin wrote:
> It might be a good idea to explicitly specify BFD format
> depending on -EB/-EL option passed to the linker and not rely on
> default behavior as we have now.

What exactly is the problem we are trying to solve here ?
Is this preventive or did you run into something - if latter can u explain it here
please ?

> Description of the OUTPUT_FORMAT command is available here:
> https://sourceware.org/binutils/docs/ld/Format-Commands.html#Format-Commands
>
> Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
> Cc: Cupertino Miranda <cmiranda@synopsys.com>
> Cc: Claudiu Zissulescu <claziss@synopsys.com>
> ---
>  arch/arc/kernel/vmlinux.lds.S | 1 +
>  1 file changed, 1 insertion(+)
>
> diff --git a/arch/arc/kernel/vmlinux.lds.S b/arch/arc/kernel/vmlinux.lds.S
> index f35ed578e007..0a1affc56d76 100644
> --- a/arch/arc/kernel/vmlinux.lds.S
> +++ b/arch/arc/kernel/vmlinux.lds.S
> @@ -11,6 +11,7 @@
>  #include <asm/page.h>
>  #include <asm/thread_info.h>
>  
> +OUTPUT_FORMAT("elf32-littlearc", "elf32-bigarc", "elf32-littlearc")
>  OUTPUT_ARCH(arc)
>  ENTRY(res_service)
>  

Re: [PATCH] ARC: Explicitly specify OUTPUT_FORMAT in the linker script

[Alexey Brodkin]

Hi Vineet,

On Fri, 2018-06-01 at 09:12 -0700, Vineet Gupta wrote:
> On 06/01/2018 03:49 AM, Alexey Brodkin wrote:
> > It might be a good idea to explicitly specify BFD format
> > depending on -EB/-EL option passed to the linker and not rely on
> > default behavior as we have now.
> 
> What exactly is the problem we are trying to solve here ?
> Is this preventive or did you run into something - if latter can u explain it here
> please ?

Right, this is preventive patch.
As Claus mentioned that's good to have this explicit information for BFD but
otherwise there's no clear requirement or even recommendation on OUTPUT_FORMAT
usage so that might not be needed.

-Alexey