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* [Bug fortran/38504] New: double minus sign when printing integer?
@ 2008-12-12 13:15 kloedej at knmi dot nl
2008-12-12 13:58 ` [Bug fortran/38504] " dfranke at gcc dot gnu dot org
` (12 more replies)
0 siblings, 13 replies; 14+ messages in thread
From: kloedej at knmi dot nl @ 2008-12-12 13:15 UTC (permalink / raw)
To: gcc-bugs
There seems to be a small bug when writing an 8 byte integer to a character
variable, as shown by this little test program:
program IntAdtest
integer, parameter :: i8_ = Selected_Int_Kind(18) ! = integer*8
character(len=22) :: str_value
integer(i8_) :: value
character(len=*), parameter :: format_IntAd = "(i22)"
value = -9223372036854775807_i8_
write(str_value, format_IntAd) value
print *,"str_value = ["//str_value//"]"
value = -9223372036854775807_i8_ -1
write(str_value, format_IntAd) value
print *,"str_value = ["//str_value//"]"
end program IntAdtest
When compiled with: gfortran -o IntAdtest IntAdtest.F90
I get the following output for the gfortran compiled executable:
>IntAdtest
str_value = [ -9223372036854775807]
str_value = [ --9223372036854775808]
For all several other compilers the result is as expected:
>IntAdtest
str_value = [ -9223372036854775807]
str_value = [ -9223372036854775808]
I used the following gfortran version for this test:
gfortran --version
GNU Fortran (GCC) 4.4.0 20081021 (experimental) [trunk revision 141258]
Copyright (C) 2008 Free Software Foundation, Inc.
best regards,
Jos de Kloe
--
Summary: double minus sign when printing integer?
Product: gcc
Version: 4.4.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: fortran
AssignedTo: unassigned at gcc dot gnu dot org
ReportedBy: kloedej at knmi dot nl
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=38504
^ permalink raw reply [flat|nested] 14+ messages in thread
* [Bug fortran/38504] double minus sign when printing integer?
2008-12-12 13:15 [Bug fortran/38504] New: double minus sign when printing integer? kloedej at knmi dot nl
@ 2008-12-12 13:58 ` dfranke at gcc dot gnu dot org
2008-12-12 14:48 ` kloedej at knmi dot nl
` (11 subsequent siblings)
12 siblings, 0 replies; 14+ messages in thread
From: dfranke at gcc dot gnu dot org @ 2008-12-12 13:58 UTC (permalink / raw)
To: gcc-bugs
------- Comment #1 from dfranke at gcc dot gnu dot org 2008-12-12 13:55 -------
Sort of confirmed. You are aware that 'value-1' corresponds to
'-HUGE(value)-1', which is out of range for integer numbers of that kind?
Reduced testcase:
IntAdtest
integer, parameter :: i8_ = Selected_Int_Kind(18) ! = integer*8
integer(i8_) :: value
value = -9223372036854775807_i8_
write(*, FMT="(i22)") value, -HUGE(value)
value = -9223372036854775807_i8_ -1
write(*, FMT="(i22)") value, -HUGE(value)-1
end program IntAdtest
Adding Jerry as CC.
--
dfranke at gcc dot gnu dot org changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |dfranke at gcc dot gnu dot
| |org, jvdelisle at gcc dot
| |gnu dot org
Status|UNCONFIRMED |NEW
Ever Confirmed|0 |1
Last reconfirmed|0000-00-00 00:00:00 |2008-12-12 13:55:55
date| |
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=38504
^ permalink raw reply [flat|nested] 14+ messages in thread
* [Bug fortran/38504] double minus sign when printing integer?
2008-12-12 13:15 [Bug fortran/38504] New: double minus sign when printing integer? kloedej at knmi dot nl
2008-12-12 13:58 ` [Bug fortran/38504] " dfranke at gcc dot gnu dot org
@ 2008-12-12 14:48 ` kloedej at knmi dot nl
2008-12-12 15:17 ` kargl at gcc dot gnu dot org
` (10 subsequent siblings)
12 siblings, 0 replies; 14+ messages in thread
From: kloedej at knmi dot nl @ 2008-12-12 14:48 UTC (permalink / raw)
To: gcc-bugs
------- Comment #2 from kloedej at knmi dot nl 2008-12-12 14:47 -------
(In reply to comment #1)
> Sort of confirmed. You are aware that 'value-1' corresponds to
> '-HUGE(value)-1', which is out of range for integer numbers of that kind?
Thanks for your reply.
Yes I am aware that defining an integer constant with value '-HUGE(value)-1' is
not allowed, but as far as I know the variable type is allowed to contain that
value.
So if:
value = -9223372036854775807_i8_ -1
is illegal, then something like:
value = -9223372036854775807_i8_
value = value-1
should be legal, and still be within the range of an 8 byte integer.
See also this discussion:
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=29580
Anyway, the point is that gfortran does accept this code, but if you write to a
character variable the result is strange.
Best regards,
Jos de Kloe
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=38504
^ permalink raw reply [flat|nested] 14+ messages in thread
* [Bug fortran/38504] double minus sign when printing integer?
2008-12-12 13:15 [Bug fortran/38504] New: double minus sign when printing integer? kloedej at knmi dot nl
2008-12-12 13:58 ` [Bug fortran/38504] " dfranke at gcc dot gnu dot org
2008-12-12 14:48 ` kloedej at knmi dot nl
@ 2008-12-12 15:17 ` kargl at gcc dot gnu dot org
2008-12-12 16:00 ` dfranke at gcc dot gnu dot org
` (9 subsequent siblings)
12 siblings, 0 replies; 14+ messages in thread
From: kargl at gcc dot gnu dot org @ 2008-12-12 15:17 UTC (permalink / raw)
To: gcc-bugs
------- Comment #3 from kargl at gcc dot gnu dot org 2008-12-12 15:15 -------
(In reply to comment #1)
> Sort of confirmed. You are aware that 'value-1' corresponds to
> '-HUGE(value)-1', which is out of range for integer numbers of that kind?
>
( Ihaven't had my morning coffe, but ...)
No. It is in range. It is the only way (other than TRANSFER) to
get the most negative integer value in a simple assignment. Now,
if you write
value = 9223372036854775807_i8_ + 1
write(*, FMT="(i22)") value, HUGE(value)+1
This results in out of range values, and wrap around semantics
still gives
--9223372036854775808
--9223372036854775808
Also, note that if one uses integer(4), you get the right output.
-2147483647
-2147483647
-2147483648
-2147483648
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=38504
^ permalink raw reply [flat|nested] 14+ messages in thread
* [Bug fortran/38504] double minus sign when printing integer?
2008-12-12 13:15 [Bug fortran/38504] New: double minus sign when printing integer? kloedej at knmi dot nl
` (2 preceding siblings ...)
2008-12-12 15:17 ` kargl at gcc dot gnu dot org
@ 2008-12-12 16:00 ` dfranke at gcc dot gnu dot org
2008-12-12 16:04 ` kargl at gcc dot gnu dot org
` (8 subsequent siblings)
12 siblings, 0 replies; 14+ messages in thread
From: dfranke at gcc dot gnu dot org @ 2008-12-12 16:00 UTC (permalink / raw)
To: gcc-bugs
------- Comment #4 from dfranke at gcc dot gnu dot org 2008-12-12 15:59 -------
> > Sort of confirmed. You are aware that 'value-1' corresponds to
> > '-HUGE(value)-1', which is out of range for integer numbers of that kind?
>
> No. It is in range.
Loose wording on my side, s/range/model/ then :)
*hands over a cup of morning coffee*
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=38504
^ permalink raw reply [flat|nested] 14+ messages in thread
* [Bug fortran/38504] double minus sign when printing integer?
2008-12-12 13:15 [Bug fortran/38504] New: double minus sign when printing integer? kloedej at knmi dot nl
` (3 preceding siblings ...)
2008-12-12 16:00 ` dfranke at gcc dot gnu dot org
@ 2008-12-12 16:04 ` kargl at gcc dot gnu dot org
2008-12-13 11:20 ` burnus at gcc dot gnu dot org
` (7 subsequent siblings)
12 siblings, 0 replies; 14+ messages in thread
From: kargl at gcc dot gnu dot org @ 2008-12-12 16:04 UTC (permalink / raw)
To: gcc-bugs
------- Comment #5 from kargl at gcc dot gnu dot org 2008-12-12 16:03 -------
Looking at the -fdump-tree-original, I suspect that the minus sign in
the hex formatted number is redundant. To keep things short, I've removed
the dt_parm setup code. _gfortran_transfer_integer probably outputs -,
then converts 0x80000000000000 to -9223....
value = -0x8000000000000000;
{
struct __st_parameter_dt dt_parm.2;
_gfortran_transfer_integer (&dt_parm.2, &value, 8);
{
static integer(kind=8) C.1495 = -0x8000000000000000;
_gfortran_transfer_integer (&dt_parm.2, &C.1495, 8);
}
_gfortran_st_write_done (&dt_parm.2);
}
value4 = -2147483648;
{
struct __st_parameter_dt dt_parm.4;
_gfortran_st_write (&dt_parm.4);
_gfortran_transfer_integer (&dt_parm.4, &value4, 4);
{
static integer(kind=4) C.1499 = -2147483648;
_gfortran_transfer_integer (&dt_parm.4, &C.1499, 4);
}
_gfortran_st_write_done (&dt_parm.4);
}
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=38504
^ permalink raw reply [flat|nested] 14+ messages in thread
* [Bug fortran/38504] double minus sign when printing integer?
2008-12-12 13:15 [Bug fortran/38504] New: double minus sign when printing integer? kloedej at knmi dot nl
` (4 preceding siblings ...)
2008-12-12 16:04 ` kargl at gcc dot gnu dot org
@ 2008-12-13 11:20 ` burnus at gcc dot gnu dot org
2008-12-13 15:33 ` jvdelisle at gcc dot gnu dot org
` (6 subsequent siblings)
12 siblings, 0 replies; 14+ messages in thread
From: burnus at gcc dot gnu dot org @ 2008-12-13 11:20 UTC (permalink / raw)
To: gcc-bugs
------- Comment #6 from burnus at gcc dot gnu dot org 2008-12-13 11:19 -------
For completeness, on my x86-64-linux system I get with 4.4.0, 4.3.0 and with
openSUSE binaries (4.1, 4.2, 4.3, 4.4) always a single "-".
Hmm, OK found something: With -m32 I get "--" but with -m64 (default) I get
"-", maybe it helps.
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=38504
^ permalink raw reply [flat|nested] 14+ messages in thread
* [Bug fortran/38504] double minus sign when printing integer?
2008-12-12 13:15 [Bug fortran/38504] New: double minus sign when printing integer? kloedej at knmi dot nl
` (5 preceding siblings ...)
2008-12-13 11:20 ` burnus at gcc dot gnu dot org
@ 2008-12-13 15:33 ` jvdelisle at gcc dot gnu dot org
2008-12-13 15:43 ` jvdelisle at gcc dot gnu dot org
` (5 subsequent siblings)
12 siblings, 0 replies; 14+ messages in thread
From: jvdelisle at gcc dot gnu dot org @ 2008-12-13 15:33 UTC (permalink / raw)
To: gcc-bugs
------- Comment #7 from jvdelisle at gcc dot gnu dot org 2008-12-13 15:32 -------
I have also found on pr38472 some odd behaviour at -m32. That we see this with
an integer output has my concern level up.
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=38504
^ permalink raw reply [flat|nested] 14+ messages in thread
* [Bug fortran/38504] double minus sign when printing integer?
2008-12-12 13:15 [Bug fortran/38504] New: double minus sign when printing integer? kloedej at knmi dot nl
` (6 preceding siblings ...)
2008-12-13 15:33 ` jvdelisle at gcc dot gnu dot org
@ 2008-12-13 15:43 ` jvdelisle at gcc dot gnu dot org
2008-12-13 16:29 ` jvdelisle at gcc dot gnu dot org
` (4 subsequent siblings)
12 siblings, 0 replies; 14+ messages in thread
From: jvdelisle at gcc dot gnu dot org @ 2008-12-13 15:43 UTC (permalink / raw)
To: gcc-bugs
------- Comment #8 from jvdelisle at gcc dot gnu dot org 2008-12-13 15:42 -------
Reduced test case. Fails at -m32
program IntAdtest
integer, parameter :: i8_ = Selected_Int_Kind(18) ! = integer*8
integer(i8_) :: value
value = -9223372036854775807_i8_ -1
write(*, '(i22)') value
end program IntAdtest
-fdump-tree-original looks clean
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=38504
^ permalink raw reply [flat|nested] 14+ messages in thread
* [Bug fortran/38504] double minus sign when printing integer?
2008-12-12 13:15 [Bug fortran/38504] New: double minus sign when printing integer? kloedej at knmi dot nl
` (7 preceding siblings ...)
2008-12-13 15:43 ` jvdelisle at gcc dot gnu dot org
@ 2008-12-13 16:29 ` jvdelisle at gcc dot gnu dot org
2008-12-13 19:36 ` jvdelisle at gcc dot gnu dot org
` (3 subsequent siblings)
12 siblings, 0 replies; 14+ messages in thread
From: jvdelisle at gcc dot gnu dot org @ 2008-12-13 16:29 UTC (permalink / raw)
To: gcc-bugs
------- Comment #9 from jvdelisle at gcc dot gnu dot org 2008-12-13 16:28 -------
I have isolated the problem to gfc_itoa. gfc_itoa returns a string. The number
of digits is determined from the strlen of that string. At -m32, that string
length (digits, see below) is off by one. I instrumented write_decimal in
write.c to see this. I now will dig into gfc_itoa.
$ gfc -m64 pr38504.f90
$ ./a.out
sign=1
w=22, m=-1, digits=19, nsign=1
-9223372036854775808
$ gfc -m32 pr38504.f90
$ ./a.out
sign=1
w=22, m=-1, digits=20, nsign=1
--9223372036854775808
--
jvdelisle at gcc dot gnu dot org changed:
What |Removed |Added
----------------------------------------------------------------------------
AssignedTo|unassigned at gcc dot gnu |jvdelisle at gcc dot gnu dot
|dot org |org
Status|NEW |ASSIGNED
Last reconfirmed|2008-12-12 13:55:55 |2008-12-13 16:28:33
date| |
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=38504
^ permalink raw reply [flat|nested] 14+ messages in thread
* [Bug fortran/38504] double minus sign when printing integer?
2008-12-12 13:15 [Bug fortran/38504] New: double minus sign when printing integer? kloedej at knmi dot nl
` (8 preceding siblings ...)
2008-12-13 16:29 ` jvdelisle at gcc dot gnu dot org
@ 2008-12-13 19:36 ` jvdelisle at gcc dot gnu dot org
2008-12-14 6:53 ` jvdelisle at gcc dot gnu dot org
` (2 subsequent siblings)
12 siblings, 0 replies; 14+ messages in thread
From: jvdelisle at gcc dot gnu dot org @ 2008-12-13 19:36 UTC (permalink / raw)
To: gcc-bugs
------- Comment #10 from jvdelisle at gcc dot gnu dot org 2008-12-13 19:34 -------
Testing this.
Index: write.c
===================================================================
--- write.c (revision 142574)
+++ write.c (working copy)
@@ -600,9 +600,16 @@ write_decimal (st_parameter_dt *dtp, con
sign = calculate_sign (dtp, n < 0);
if (n < 0)
n = -n;
-
nsign = sign == S_NONE ? 0 : 1;
+
+ /* conv calls gfc_itoa which sets the negative sign needed
+ by write_integer. The sign '+' or '-' is set below based on sign
+ calculated above, so we just point past the sign in the string
+ before proceeding to avoid double signs in corner cases.
+ (see PR38504) */
q = conv (n, itoa_buf, sizeof (itoa_buf));
+ if (*q == '-')
+ q++;
digits = strlen (q);
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=38504
^ permalink raw reply [flat|nested] 14+ messages in thread
* [Bug fortran/38504] double minus sign when printing integer?
2008-12-12 13:15 [Bug fortran/38504] New: double minus sign when printing integer? kloedej at knmi dot nl
` (9 preceding siblings ...)
2008-12-13 19:36 ` jvdelisle at gcc dot gnu dot org
@ 2008-12-14 6:53 ` jvdelisle at gcc dot gnu dot org
2008-12-14 7:01 ` jvdelisle at gcc dot gnu dot org
2008-12-14 7:03 ` jvdelisle at gcc dot gnu dot org
12 siblings, 0 replies; 14+ messages in thread
From: jvdelisle at gcc dot gnu dot org @ 2008-12-14 6:53 UTC (permalink / raw)
To: gcc-bugs
------- Comment #11 from jvdelisle at gcc dot gnu dot org 2008-12-14 06:52 -------
Subject: Bug 38504
Author: jvdelisle
Date: Sun Dec 14 06:50:53 2008
New Revision: 142747
URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=142747
Log:
2008-12-13 Jerry DeLisle <jvdelisle@gcc.gnu.org>
PR libfortran/38504
io/write.c (write_decimal): Skip extra sign '-' at beginning of string
returned by gfc_itoa.
Modified:
trunk/libgfortran/ChangeLog
trunk/libgfortran/io/write.c
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=38504
^ permalink raw reply [flat|nested] 14+ messages in thread
* [Bug fortran/38504] double minus sign when printing integer?
2008-12-12 13:15 [Bug fortran/38504] New: double minus sign when printing integer? kloedej at knmi dot nl
` (10 preceding siblings ...)
2008-12-14 6:53 ` jvdelisle at gcc dot gnu dot org
@ 2008-12-14 7:01 ` jvdelisle at gcc dot gnu dot org
2008-12-14 7:03 ` jvdelisle at gcc dot gnu dot org
12 siblings, 0 replies; 14+ messages in thread
From: jvdelisle at gcc dot gnu dot org @ 2008-12-14 7:01 UTC (permalink / raw)
To: gcc-bugs
------- Comment #12 from jvdelisle at gcc dot gnu dot org 2008-12-14 07:00 -------
Subject: Bug 38504
Author: jvdelisle
Date: Sun Dec 14 06:58:38 2008
New Revision: 142748
URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=142748
Log:
2008-12-13 Jerry DeLisle <jvdelisle@gcc.gnu.org>
PR libfortran/38504
* gfortran.dg/fmt_int_sign.f90: New test.
Added:
trunk/gcc/testsuite/gfortran.dg/fmt_int_sign.f90
Modified:
trunk/gcc/testsuite/ChangeLog
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=38504
^ permalink raw reply [flat|nested] 14+ messages in thread
* [Bug fortran/38504] double minus sign when printing integer?
2008-12-12 13:15 [Bug fortran/38504] New: double minus sign when printing integer? kloedej at knmi dot nl
` (11 preceding siblings ...)
2008-12-14 7:01 ` jvdelisle at gcc dot gnu dot org
@ 2008-12-14 7:03 ` jvdelisle at gcc dot gnu dot org
12 siblings, 0 replies; 14+ messages in thread
From: jvdelisle at gcc dot gnu dot org @ 2008-12-14 7:03 UTC (permalink / raw)
To: gcc-bugs
------- Comment #13 from jvdelisle at gcc dot gnu dot org 2008-12-14 07:01 -------
Fixed on trunk.
--
jvdelisle at gcc dot gnu dot org changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|ASSIGNED |RESOLVED
Resolution| |FIXED
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=38504
^ permalink raw reply [flat|nested] 14+ messages in thread
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2008-12-12 13:15 [Bug fortran/38504] New: double minus sign when printing integer? kloedej at knmi dot nl
2008-12-12 13:58 ` [Bug fortran/38504] " dfranke at gcc dot gnu dot org
2008-12-12 14:48 ` kloedej at knmi dot nl
2008-12-12 15:17 ` kargl at gcc dot gnu dot org
2008-12-12 16:00 ` dfranke at gcc dot gnu dot org
2008-12-12 16:04 ` kargl at gcc dot gnu dot org
2008-12-13 11:20 ` burnus at gcc dot gnu dot org
2008-12-13 15:33 ` jvdelisle at gcc dot gnu dot org
2008-12-13 15:43 ` jvdelisle at gcc dot gnu dot org
2008-12-13 16:29 ` jvdelisle at gcc dot gnu dot org
2008-12-13 19:36 ` jvdelisle at gcc dot gnu dot org
2008-12-14 6:53 ` jvdelisle at gcc dot gnu dot org
2008-12-14 7:01 ` jvdelisle at gcc dot gnu dot org
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