confused on xfail in pr41353-1.c by guality.exp

[陈龙]

Hi,

 

The pr41353-1.c  case had confused me a long time. I have been looking for the answer with any ways I can but no satisfied consequence for me . So appreciate the support very much.  Details as below:

 

Environment:

 

windows7, MinGW, gcc7.3.0 test suite, DejaGNU1.6

 

Relative code(/gcc/testsuite/gcc.dg/guality/pr41353.c):

 

__attribute__((noinline)) int

f2 (int i, int j)

{

  j += i;

  /* { dg-final { gdb-test 28 "i" "37" } } */

  /* { dg-final { gdb-test 28 "j" "28 + 37" { xfail *-*-* } } } */

  int i1 = 2 * i; /* { dg-final { gdb-test 28 "i1" "2 * 37" } } */

  int i2 = 3 * i; /* { dg-final { gdb-test 28 "i2" "3 * 37" } } */

  return j;

}

 

int (*volatile fnp1) (void) = f1;

int (*volatile fnp2) (int, int) = f2;

int (*volatile fnp3) (int) = f3;

 

int

main (int argc, char *argv[])

{

  asm volatile ("" : : "r" (&fnp1) : "memory");

  asm volatile ("" : : "r" (&fnp2) : "memory");

  asm volatile ("" : : "r" (&fnp3) : "memory");

  fnp1 ();

  fnp2 (37, 28);

  fnp3 (12);

  return 0;

}

 

LOG:

Closing the remote shell exp8

doing kill, pid is 10568

pid is 10568

Shell closed.

replacement dg-process-target: `{ xfail *-*-* }'

dg-process-target-1: `{xfail *-*-*}'

Checking "*-*-*" against "i686-w64-mingw32"

Spawning: gdb -nx -nw -quiet -batch -x pr41353-1.gdb ./pr41353-1.exe

spawning command gdb -nx -nw -quiet -batch -x pr41353-1.gdb ./pr41353-1.exe

spawn gdb -nx -nw -quiet -batch -x pr41353-1.gdb ./pr41353-1.exe

Breakpoint 1 at 0x4015d8: file ././gcc.dg/guality/pr41353-1.c, line 28.

[New Thread 7492.0x25c8]

 

Breakpoint 1, f2 (i=37, j=65) at ././gcc.dg/guality/pr41353-1.c:29

29           }

$1 = 65

$2 = 65

A debugging session is active.

 

                Inferior 1 [process 7492] will be killed.

 

Quit anyway? (y or n) [answered Y; input not from terminal]

XPASS: ./gcc.dg/guality/pr41353-1.c   -O2 -flto -fuse-linker-plugin -fno-fat-lto-objects  line 28 j == 28 + 37

 

 

 

I don‘t understand why the gdb-test 28 "j" "28 + 37" should be failed. I get some explanation from “https://gcc.gnu.org/ml/gcc-patches/2009-09/msg01162.html”, some information was picked up here:

 

the current guality infrastructure isn't useful, because the guality checks involve a function call which invalidates any memory and registers in which arguments are passed, so values can't be expected to be available in many cases.

 

It looks like a bug in version before, the information record in 17-Sep,2009, and the gcc version is 4.5 , so I’m not sure it is right for the case now. Or the bug is fixed but the case don’t modify Synchronously? just an assumption.

 

 

Best regards,

      CL