Fix riscv-linux native gdb build failure.

  The linux kernel uses NT_PRFPREG.  Glibc before BZ 14890 defines NT_FPREGSET.
After it defines both.  Avoid glibc version dependency by using the gdb header
file instead of the glibc header file, and the macro name that gdb defines
which is NT_FPREGSET.

Tested with riscv-linux make and make check with no regressions.  OK to
commit?

Jim

	gdb/
	* riscv-linux-nat.c: Include elf/common.h instead of elf.h.
	(riscv_linux_nat_target::fetch_registers): Use NT_FPREGSET instead
	of NT_PRFPREG.
	(riscv_linux_nat_target::store_registers): Likewise.
---
 gdb/riscv-linux-nat.c | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)
  

* Jim Wilson <jimw@sifive.com> [2018-08-28 16:04:40 -0700]:

> The linux kernel uses NT_PRFPREG.  Glibc before BZ 14890 defines NT_FPREGSET.
> After it defines both.  Avoid glibc version dependency by using the gdb header
> file instead of the glibc header file, and the macro name that gdb defines
> which is NT_FPREGSET.
> 
> Tested with riscv-linux make and make check with no regressions.  OK to
> commit?
> 
> Jim
> 
> 	gdb/
> 	* riscv-linux-nat.c: Include elf/common.h instead of elf.h.
> 	(riscv_linux_nat_target::fetch_registers): Use NT_FPREGSET instead
> 	of NT_PRFPREG.
> 	(riscv_linux_nat_target::store_registers): Likewise.


Looks good to me.

Thanks,
Andrew

> ---
>  gdb/riscv-linux-nat.c | 9 +++++----
>  1 file changed, 5 insertions(+), 4 deletions(-)
> 
> diff --git a/gdb/riscv-linux-nat.c b/gdb/riscv-linux-nat.c
> index 3faa9f9c1f..7dbfe651f2 100644
> --- a/gdb/riscv-linux-nat.c
> +++ b/gdb/riscv-linux-nat.c
> @@ -20,9 +20,10 @@
>  #include "regcache.h"
>  #include "gregset.h"
>  #include "linux-nat.h"
> -#include "elf.h"
>  #include "riscv-tdep.h"
>  
> +#include "elf/common.h"
> +
>  #include <sys/ptrace.h>
>  
>  /* RISC-V Linux native additions to the default linux support.  */
> @@ -191,7 +192,7 @@ riscv_linux_nat_target::fetch_registers (struct regcache *regcache, int regnum)
>        iov.iov_base = &regs;
>        iov.iov_len = sizeof (regs);
>  
> -      if (ptrace (PTRACE_GETREGSET, tid, NT_PRFPREG,
> +      if (ptrace (PTRACE_GETREGSET, tid, NT_FPREGSET,
>  		  (PTRACE_TYPE_ARG3) &iov) == -1)
>  	perror_with_name (_("Couldn't get registers"));
>        else
> @@ -252,14 +253,14 @@ riscv_linux_nat_target::store_registers (struct regcache *regcache, int regnum)
>        iov.iov_base = &regs;
>        iov.iov_len = sizeof (regs);
>  
> -      if (ptrace (PTRACE_GETREGSET, tid, NT_PRFPREG,
> +      if (ptrace (PTRACE_GETREGSET, tid, NT_FPREGSET,
>  		  (PTRACE_TYPE_ARG3) &iov) == -1)
>  	perror_with_name (_("Couldn't get registers"));
>        else
>  	{
>  	  fill_fpregset (regcache, &regs, regnum);
>  
> -	  if (ptrace (PTRACE_SETREGSET, tid, NT_PRFPREG,
> +	  if (ptrace (PTRACE_SETREGSET, tid, NT_FPREGSET,
>  		      (PTRACE_TYPE_ARG3) &iov) == -1)
>  	    perror_with_name (_("Couldn't set registers"));
>  	}
> -- 
> 2.17.1
>
  

On Wed, Aug 29, 2018 at 3:44 AM, Andrew Burgess
<andrew.burgess@embecosm.com> wrote:
> * Jim Wilson <jimw@sifive.com> [2018-08-28 16:04:40 -0700]:
>>       gdb/
>>       * riscv-linux-nat.c: Include elf/common.h instead of elf.h.
>>       (riscv_linux_nat_target::fetch_registers): Use NT_FPREGSET instead
>>       of NT_PRFPREG.
>>       (riscv_linux_nat_target::store_registers): Likewise.
>
> Looks good to me.

Thanks.  Committed.

Jim