Re: Oh dear. I regret to inform you that commit de52b9607d2623f18b7a7dbee3e1123d8d63f5da might be unfortunate

[Joel Brobecker <brobecker@adacore.com>]

> I'm still seeing a breakage here on x86-64 Fedora GNU/Linux, when
> building gdbserver:
> 
>   ../../../binutils-gdb/gdb/gdbserver/linux-x86-tdesc.c: In function ‘const target_desc* amd64_linux_read_description(uint64_t, bool)’:
>   ../../../binutils-gdb/gdb/gdbserver/linux-x86-tdesc.c:121:67: error: too few arguments to function ‘target_desc* amd64_create_target_description(uint64_t, bool, bool, bool)’
>          *tdesc = amd64_create_target_description (xcr0, is_x32, true);
>                                                                      ^
>   In file included from ../../../binutils-gdb/gdb/gdbserver/linux-x86-tdesc.c:26:0:
>   ../../../binutils-gdb/gdb/gdbserver/../arch/amd64.h:21:14: note: declared here
>    target_desc *amd64_create_target_description (uint64_t xcr0, bool is_x32,
>                 ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> 
> Does the patch below make sense?  It fixes the breakage for me.

Thanks for looking into it and the patch!

I think the parameter should be set to "true". Otherwise, it will
not include the fs_base and gs_base register in the list of registers.
Although the name of the source file says x86, the code itself is
protected by...

    #ifdef __x86_64__

... and is inside a function called amd64_linux_read_description.
I also verified that this file gets compiled on amd64-linux platforms.
See gdb/gdbserver/configure.srv:

  x86_64-*-linux*)      srv_regobj="$srv_amd64_linux_regobj $srv_i386_linux_regobj"

The last piece of confirmation is that setting the parameter to "true"
provides the behavior before the parameter was added; and the reason
for adding the parameter was to remove the {fs,gs}_base registers
from the list for Windows only.

Otherwise the rest (basically the ChangeLog) looks good.

Thanks again!

> diff --git a/gdb/gdbserver/ChangeLog b/gdb/gdbserver/ChangeLog
> index 2fd2d90a49..743d465d81 100644
> --- a/gdb/gdbserver/ChangeLog
> +++ b/gdb/gdbserver/ChangeLog
> @@ -1,3 +1,8 @@
> +2018-06-29  Sergio Durigan Junior  <sergiodj@redhat.com>
> +
> +	* linux-x86-tdesc.c (amd64_linux_read_description): Add missing
> +	parameter in call to 'amd64_create_target_description'.
> +
>  2018-06-28  Jan Kratochvil  <jan.kratochvil@redhat.com>
>  
>  	* x86-tdesc.h: Remove executable permission flag.
> diff --git a/gdb/gdbserver/linux-x86-tdesc.c b/gdb/gdbserver/linux-x86-tdesc.c
> index 358659b295..7a45953dc9 100644
> --- a/gdb/gdbserver/linux-x86-tdesc.c
> +++ b/gdb/gdbserver/linux-x86-tdesc.c
> @@ -118,7 +118,7 @@ amd64_linux_read_description (uint64_t xcr0, bool is_x32)
>  
>    if (*tdesc == NULL)
>      {
> -      *tdesc = amd64_create_target_description (xcr0, is_x32, true);
> +      *tdesc = amd64_create_target_description (xcr0, is_x32, true, false);
>  
>        init_target_desc (*tdesc, amd64_expedite_regs);
>      }

-- 
Joel