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From: "ppalka at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug libstdc++/98384] [11 Regression] new test case 20_util/to_chars/long_double.cc in r11-6249 fails on powerpc64 BE
Date: Mon, 08 Mar 2021 17:42:43 +0000	[thread overview]
Message-ID: <bug-98384-4-REXGtQyZWg@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-98384-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98384

--- Comment #24 from Patrick Palka <ppalka at gcc dot gnu.org> ---
(In reply to David Edelsohn from comment #23)
> The AIX failure is:
> 
> printf_buffer=
> 1.
> 44269504088896338700465094007086008800000000000000000000000000000000000000000
> 00000000000000000000000 
> 
> to_chars_buffer=
> 1.
> 44269504088896338700465094007086008787155151367187500000000000000000000000000
> 00000000000000000000000??/?P00001.
> 44269504088896338700465094007086008800000000000000000000000000000000000000000
> 00000000000000000000000
> 
> output_length=
> 102
> 
> ./long_double.cc:194: void test02(): Assertion '!memcmp(printf_buffer,
> to_chars_buffer, output_length)' failed.

I managed to reproduce this issue on AIX (gcc119).  It looks like the %e/%f/%g
specifiers (as well as %Le/%Lf/%Lg -- long double is equivalent to double)
never output more than 37 significant decimal digits on AIX.

For e.g.

  printf("%.53e\n", 0x1.71547652b82fep+0);
  printf("%.0f\n", 0x1.249ad2594c37dp+332);

x86 glibc printf outputs

  1.44269504088896338700465094007086008787155151367187500e+00
 
10000000000000000159028911097599180468360808563945281389781327557747838772170381060813469985856815104

and AIX printf outputs

  1.44269504088896338700465094007086008800000000000000000e+00
 
10000000000000000159028911097599180470000000000000000000000000000000000000000000000000000000000000000

It seems to me the output of AIX printf is wrong/nonconforming here..

  parent reply	other threads:[~2021-03-08 17:42 UTC|newest]

Thread overview: 42+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-12-18 21:39 [Bug libstdc++/98384] New: " seurer at gcc dot gnu.org
2020-12-21 20:28 ` [Bug libstdc++/98384] " ppalka at gcc dot gnu.org
2020-12-22  9:23 ` ro at gcc dot gnu.org
2021-01-05  9:10 ` [Bug libstdc++/98384] [11 Regression] " rguenth at gcc dot gnu.org
2021-01-07 13:04 ` iains at gcc dot gnu.org
2021-01-07 15:42 ` ppalka at gcc dot gnu.org
2021-01-07 16:41 ` iains at gcc dot gnu.org
2021-01-07 17:42 ` cvs-commit at gcc dot gnu.org
2021-01-07 17:55 ` ppalka at gcc dot gnu.org
2021-01-08  9:30 ` ro at CeBiTec dot Uni-Bielefeld.DE
2021-01-12 16:35 ` ppalka at gcc dot gnu.org
2021-01-14 11:13 ` rguenth at gcc dot gnu.org
2021-02-12 15:02 ` jakub at gcc dot gnu.org
2021-02-23  2:49 ` cvs-commit at gcc dot gnu.org
2021-02-23 16:55 ` ppalka at gcc dot gnu.org
2021-02-24  9:58 ` ro at CeBiTec dot Uni-Bielefeld.DE
2021-02-24 15:14 ` ppalka at gcc dot gnu.org
2021-02-24 15:42 ` ro at CeBiTec dot Uni-Bielefeld.DE
2021-02-24 15:48 ` jakub at gcc dot gnu.org
2021-02-24 16:16 ` ppalka at gcc dot gnu.org
2021-02-24 16:26 ` iains at gcc dot gnu.org
2021-02-24 16:45 ` ppalka at gcc dot gnu.org
2021-02-24 17:26 ` cvs-commit at gcc dot gnu.org
2021-02-27 16:17 ` iains at gcc dot gnu.org
2021-02-27 16:49 ` dje at gcc dot gnu.org
2021-03-03 14:28 ` ppalka at gcc dot gnu.org
2021-03-05  2:37 ` dje at gcc dot gnu.org
2021-03-08 17:42 ` ppalka at gcc dot gnu.org [this message]
2021-03-08 17:53 ` schwab@linux-m68k.org
2021-03-08 19:27 ` dje at gcc dot gnu.org
2021-03-08 21:09 ` iains at gcc dot gnu.org
2021-03-08 21:24 ` iains at gcc dot gnu.org
2021-03-09  9:55 ` iains at gcc dot gnu.org
2021-03-10 14:28 ` ppalka at gcc dot gnu.org
2021-03-10 14:51 ` ppalka at gcc dot gnu.org
2021-04-08 15:11 ` cvs-commit at gcc dot gnu.org
2021-04-08 15:22 ` [Bug libstdc++/98384] new test case 20_util/to_chars/long_double.cc in r11-6249 fails ppalka at gcc dot gnu.org
2021-04-08 16:22 ` redi at gcc dot gnu.org
2021-04-27 11:39 ` jakub at gcc dot gnu.org
2021-07-28  7:05 ` rguenth at gcc dot gnu.org
2022-04-21  7:48 ` rguenth at gcc dot gnu.org
2023-05-29 10:03 ` jakub at gcc dot gnu.org

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