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Description of problem:
I have a simple program to read the ar.rnat register. In order to test this, I use gdb to set ar.rnat to a value.
Although printing the contents of ar.rnat from gdb indicates that the value was changed, the program output shows that the ar.rnat was not changes, 
and still reads as 0

Version-Release number of selected component (if applicable):
Fails with both gdb-5.1-1 or gdb-5.2-2

How reproducible:
Always

Steps to Reproduce:
1.      .file "get_rnat.asm"
      .text
      .align 16
      .global get_rnat#
      .proc get_rnat#
// Function Prototype is uint64_t get_rnat(void)
get_rnat:
      mov r2=ar.rsc           // preserve ar.rsc in r2
      mov r14=0x3;;           // bits zero and one
      andcm r3=r2,r14;; // r3 = r2 & ~r14
      mov ar.rsc=r3;;         // ar.rsc = enforced lazy mode
      mov r8=ar.rnat;;        // return value of ar.rnat
      mov ar.rsc=r2;;           // restore previous mode to ar.rsc

      .endp get_rnat#
You can assemble the above with as -o get_rnat.o get_rnat.asm
2. Here is a simple program to utilize the above.
/* file: try.c */
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>

extern uint64_t get_rnat(void);

int main(void)
{
      uint64_t rnat = get_rnat();
      printf("ar.rnat = %#lx\n", rnat);

      exit(0);
}
Note: I use gcc3.04
gcc -o try try.c get_rnat.o -W -Wall -g
3. Use gdb to set rnat
Now, inorder to test this, I want to use the debugger to force ar.rnat to
have a value, so I do the following.
gdb try
(gdb)br main
Breakpoint 1, 0x4000000000000692 in main ()
(gdb)run
Then the debugger stops at the breakpoint, and I do
(gdb) print $rnat=32
(gdb) c
Continuing.
ar.rnat = 0

Program exited normally.
(gdb) quit
My program reported ar.rnat as 0, even though I used gdb to force the value
to 32

If I put another breakpoint before the exit and do "info register $rnat,
then it is still 32,", but my program reports 0.
Furthermore, If I  force $rnat to a value through some asm code, and then
call get_rnat(), it works correctly.
	

Actual Results:  My program reported ar.rnat as 0, even though I used gdb to force the value
to 32

Expected Results:  The program should have output
ar.rnat = 0x20

Additional info: