From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 25783 invoked by alias); 24 Oct 2012 18:12:52 -0000 Received: (qmail 25770 invoked by uid 22791); 24 Oct 2012 18:12:51 -0000 X-SWARE-Spam-Status: No, hits=-2.3 required=5.0 tests=AWL,BAYES_00,RCVD_IN_HOSTKARMA_NO,RP_MATCHES_RCVD X-Spam-Check-By: sourceware.org Received: from rock.gnat.com (HELO rock.gnat.com) (205.232.38.15) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Wed, 24 Oct 2012 18:12:45 +0000 Received: from localhost (localhost.localdomain [127.0.0.1]) by filtered-rock.gnat.com (Postfix) with ESMTP id 08EB91C749F; Wed, 24 Oct 2012 14:12:45 -0400 (EDT) Received: from rock.gnat.com ([127.0.0.1]) by localhost (rock.gnat.com [127.0.0.1]) (amavisd-new, port 10024) with LMTP id I+wKKWXpCB+O; Wed, 24 Oct 2012 14:12:44 -0400 (EDT) Received: from joel.gnat.com (localhost.localdomain [127.0.0.1]) by rock.gnat.com (Postfix) with ESMTP id E2EEE1C745D; Wed, 24 Oct 2012 14:12:44 -0400 (EDT) Received: by joel.gnat.com (Postfix, from userid 1000) id 84ACDC88A1; Wed, 24 Oct 2012 14:12:42 -0400 (EDT) From: Joel Brobecker To: gdb-patches@sourceware.org Cc: Joel Brobecker Subject: [commit] off-by-one max exponent computation in convert_doublest_to_floatformat Date: Wed, 24 Oct 2012 18:12:00 -0000 Message-Id: <1351102361-24045-1-git-send-email-brobecker@adacore.com> Mailing-List: contact gdb-patches-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-patches-owner@sourceware.org X-SW-Source: 2012-10/txt/msg00471.txt.bz2 Hello, This is a followup on a patch I checked in a while ago. Assuming the following variable definition: long double inp = 2.0; On platforms where "long double" is a double precision IEEE floating point, GDB currently behaves as follow: (gdb) set variable inp = 1.6e+308l (gdb) p inp $2 = inf <<<<---- !!!! Instead, the value of "inp" should be printed as: (gdb) p inp $1 = 1.6e+308 The problem is due to a small error in the comparison of the exponent versus the maximum value this exponent can take, causing us to think that the value was too big to fit. But it isn't. gdb/ChangeLog: * doublest.c (convert_doublest_to_floatformat): Fix comparison against maximum exponent value. gdb/testsuite/ChangeLog: * gdb.base/ldbl_e308.c, gdb.base/ldbl_e308.exp: New files. Tested on x86_64-linux. Checked in. --- gdb/ChangeLog | 5 +++++ gdb/doublest.c | 2 +- gdb/testsuite/ChangeLog | 4 ++++ gdb/testsuite/gdb.base/ldbl_e308.c | 26 ++++++++++++++++++++++++++ gdb/testsuite/gdb.base/ldbl_e308.exp | 31 +++++++++++++++++++++++++++++++ 5 files changed, 67 insertions(+), 1 deletion(-) create mode 100644 gdb/testsuite/gdb.base/ldbl_e308.c create mode 100644 gdb/testsuite/gdb.base/ldbl_e308.exp diff --git a/gdb/ChangeLog b/gdb/ChangeLog index 4d3c3ec..20ab7a9 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,5 +1,10 @@ 2012-10-24 Joel Brobecker + * doublest.c (convert_doublest_to_floatformat): Fix comparison + against maximum exponent value. + +2012-10-24 Joel Brobecker + * ada-lang.h (ADA_KNOWN_RUNTIME_FILE_NAME_PATTERNS): Add entry for "unwind-seh.c". diff --git a/gdb/doublest.c b/gdb/doublest.c index f683002..0308dac 100644 --- a/gdb/doublest.c +++ b/gdb/doublest.c @@ -483,7 +483,7 @@ convert_doublest_to_floatformat (CONST struct floatformat *fmt, goto finalize_byteorder; } - if (exponent + fmt->exp_bias >= (1 << fmt->exp_len) - 1) + if (exponent + fmt->exp_bias >= (1 << fmt->exp_len)) { /* The value is too large to fit into the destination. Treat as infinity. */ diff --git a/gdb/testsuite/ChangeLog b/gdb/testsuite/ChangeLog index a7a1180..633c0ab 100644 --- a/gdb/testsuite/ChangeLog +++ b/gdb/testsuite/ChangeLog @@ -1,5 +1,9 @@ 2012-10-24 Joel Brobecker + * gdb.base/ldbl_e308.c, gdb.base/ldbl_e308.exp: New files. + +2012-10-24 Joel Brobecker + * gdb.ada/unc_arr_ptr_in_var_rec: New testcase. 2012-10-24 Mark Kettenis diff --git a/gdb/testsuite/gdb.base/ldbl_e308.c b/gdb/testsuite/gdb.base/ldbl_e308.c new file mode 100644 index 0000000..8bbe01b --- /dev/null +++ b/gdb/testsuite/gdb.base/ldbl_e308.c @@ -0,0 +1,26 @@ +/* Copyright (C) 2012 Free Software Foundation, Inc. + + This file is part of GDB. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see . */ + +long double ldbl_308 = 2.0; + +int +main (void) +{ + ldbl_308 = ldbl_308 / 2; + + return 0; +} diff --git a/gdb/testsuite/gdb.base/ldbl_e308.exp b/gdb/testsuite/gdb.base/ldbl_e308.exp new file mode 100644 index 0000000..89c54b5 --- /dev/null +++ b/gdb/testsuite/gdb.base/ldbl_e308.exp @@ -0,0 +1,31 @@ +# Copyright (C) 2012 Free Software Foundation, Inc. +# +# This program is free software; you can redistribute it and/or modify +# it under the terms of the GNU General Public License as published by +# the Free Software Foundation; either version 3 of the License, or +# (at your option) any later version. +# +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. +# +# You should have received a copy of the GNU General Public License +# along with this program. If not, see . + +set testfile ldbl_e308 +set srcfile ${testfile}.c +if { [prepare_for_testing ${testfile}.exp ${testfile} ${srcfile}] } { + return -1 +} + +if ![runto_main] { + untested ${testfile}.exp + return -1 +} + +gdb_test_no_output "set variable ldbl_308 = 1.6e+308l" + +gdb_test "print ldbl_308" \ + "= (1\..*e\\+308|inf)" + -- 1.7.9.5