Introduce target-specific LDFLAGS, the same way we have CFLAGS for the target.
It seems to be helping gcc somewhat into telling the correct endianness to ld that sticks with little endian even when the target is big (eg armeb-unknown-linux-uclibcgnueabi).
There's still work to do, especially finish the gcc part that is not in this commit.
/trunk/scripts/functions | 9 7 2 0 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)
1 Taken from http://sources.redhat.com/ml/crossgcc/2004-02/msg00104.html
2 Author: addsub@eyou.com
5 Fixes http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/testsuite/gcc.c-torture/execute/920501-8.c
6 and makes printf("%f", 1.0) work.
8 Lennert Buytenhek wrote in http://sources.redhat.com/ml/crossgcc/2004-09/msg00115.html :
9 It ... fixes the 'printf("%f\n", 0.5); prints 0.000000' and general 'floating point
10 is broken' on my big-endian hardfloat FPA ARM platform. ...
11 It's definitely needed for hardfloat. So I'd think it's needed for
12 big-endian systems in any case, and for VFP on little-endian systems
13 too. Someone would have to verify that though.
15 Lennert Buytenhek wrote in http://sources.redhat.com/ml/crossgcc/2004-09/msg00123.html
16 I just had a look at glibc-20040830, and [this patch] is still needed and useful
17 for this version. glibc-20040830 out-of-the-box still contains the
18 following wrong assumptions:
19 - sysdeps/arm/bits/endian.h: float word order is big endian (which it is
21 - sysdeps/arm/gmp-mparam.h: IEEE doubles are mixed endian (which they
22 are not on big endian systems, neither on vfp systems)
23 - sysdeps/arm/ieee754.h: IEEE doubles are in little endian byte order
24 (which they are not on big endian systems)
25 [This patch] seems the right solution for all of these issues.
27 Dimitry Andric wrote in http://sources.redhat.com/ml/crossgcc/2004-09/msg00132.html :
28 It's even needed for glibc CVS, AFAICS.
29 The patch hunk which modifies glibc.new/sysdeps/arm/bits/endian.h
30 (currently at version 1.4) is only needed for proper VFP operation.
31 But the hunk which modifies sysdeps/arm/gmp-mparam.h, and the hunk
32 that deletes sysdeps/arm/ieee754.h (yes, this IS correct), are needed
33 for proper operation of *any* FP model on big endian ARM.
35 See also discussion in followups to
36 http://sources.redhat.com/ml/crossgcc/2004-05/msg00245.html)
38 Message-ID: <276985760.37584@eyou.com>
39 Received: from unknown (HELO eyou.com) (172.16.2.2)
40 by 0.0.0.0 with SMTP; Tue, 17 Feb 2004 10:42:40 +0800
41 Received: (qmail 8238 invoked by uid 65534); 17 Feb 2004 10:42:38 +0800
42 Date: 17 Feb 2004 10:42:38 +0800
43 Message-ID: <20040217104238.8237.qmail@eyou.com>
44 From: "add" <addsub@eyou.com>
46 Reply-To: "add" <addsub@eyou.com>
47 Subject: Re: problem while building arm vfp softfloat gcc `
49 Hi, Dan, This is a patch I applied to my glibc-2.3.2, then my softfloat
50 toolchain can printf("%f\n",1.0). So you may have a try of this
53 diff -uNrp glibc.old/sysdeps/arm/bits/endian.h glibc.new/sysdeps/arm/bits/endian.h
54 --- glibc.old/sysdeps/arm/bits/endian.h 1999-04-12 11:59:13.000000000 -0400
55 +++ glibc.new/sysdeps/arm/bits/endian.h 2004-02-12 09:15:13.000000000 -0500
58 #define __BYTE_ORDER __LITTLE_ENDIAN
62 +#define __FLOAT_WORD_ORDER __BYTE_ORDER
64 #define __FLOAT_WORD_ORDER __BIG_ENDIAN
66 diff -uNrp glibc.old/sysdeps/arm/gmp-mparam.h glibc.new/sysdeps/arm/gmp-mparam.h
67 --- glibc.old/sysdeps/arm/gmp-mparam.h 2001-07-07 15:21:19.000000000 -0400
68 +++ glibc.new/sysdeps/arm/gmp-mparam.h 2004-02-12 09:15:13.000000000 -0500
69 @@ -26,5 +26,13 @@ MA 02111-1307, USA. */
70 #define BITS_PER_SHORTINT 16
71 #define BITS_PER_CHAR 8
73 -#define IEEE_DOUBLE_BIG_ENDIAN 0
74 -#define IEEE_DOUBLE_MIXED_ENDIAN 1
75 +#if defined(__ARMEB__)
76 +# define IEEE_DOUBLE_MIXED_ENDIAN 0
77 +# define IEEE_DOUBLE_BIG_ENDIAN 1
78 +#elif defined(__VFP_FP__)
79 +# define IEEE_DOUBLE_MIXED_ENDIAN 0
80 +# define IEEE_DOUBLE_BIG_ENDIAN 0
82 +# define IEEE_DOUBLE_BIG_ENDIAN 0
83 +# define IEEE_DOUBLE_MIXED_ENDIAN 1
85 diff -uNrp glibc.old/sysdeps/arm/ieee754.h glibc.new/sysdeps/arm/ieee754.h
86 --- glibc.old/sysdeps/arm/ieee754.h 2001-07-07 15:21:19.000000000 -0400
87 +++ glibc.new/sysdeps/arm/ieee754.h 1969-12-31 19:00:00.000000000 -0500
89 -/* Copyright (C) 1992, 1995, 1996, 1998 Free Software Foundation, Inc.
90 - This file is part of the GNU C Library.
92 - The GNU C Library is free software; you can redistribute it and/or
93 - modify it under the terms of the GNU Lesser General Public
94 - License as published by the Free Software Foundation; either
95 - version 2.1 of the License, or (at your option) any later version.
97 - The GNU C Library is distributed in the hope that it will be useful,
98 - but WITHOUT ANY WARRANTY; without even the implied warranty of
99 - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
100 - Lesser General Public License for more details.
102 - You should have received a copy of the GNU Lesser General Public
103 - License along with the GNU C Library; if not, write to the Free
104 - Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
109 -#define _IEEE754_H 1
110 -#include <features.h>
120 - /* This is the IEEE 754 single-precision format. */
123 - unsigned int mantissa:23;
124 - unsigned int exponent:8;
125 - unsigned int negative:1;
128 - /* This format makes it easier to see if a NaN is a signalling NaN. */
131 - unsigned int mantissa:22;
132 - unsigned int quiet_nan:1;
133 - unsigned int exponent:8;
134 - unsigned int negative:1;
138 -#define IEEE754_FLOAT_BIAS 0x7f /* Added to exponent. */
141 -union ieee754_double
145 - /* This is the IEEE 754 double-precision format. */
148 - unsigned int mantissa0:20;
149 - unsigned int exponent:11;
150 - unsigned int negative:1;
151 - unsigned int mantissa1:32;
154 - /* This format makes it easier to see if a NaN is a signalling NaN. */
157 - unsigned int mantissa0:19;
158 - unsigned int quiet_nan:1;
159 - unsigned int exponent:11;
160 - unsigned int negative:1;
161 - unsigned int mantissa1:32;
165 -#define IEEE754_DOUBLE_BIAS 0x3ff /* Added to exponent. */
168 -/* The following two structures are correct for `new' floating point systems but
169 - wrong for the old FPPC. The only solution seems to be to avoid their use on
172 -union ieee854_long_double
176 - /* This is the IEEE 854 double-extended-precision format. */
179 - unsigned int exponent:15;
180 - unsigned int empty:16;
181 - unsigned int negative:1;
182 - unsigned int mantissa1:32;
183 - unsigned int mantissa0:32;
186 - /* This is for NaNs in the IEEE 854 double-extended-precision format. */
189 - unsigned int exponent:15;
190 - unsigned int empty:16;
191 - unsigned int negative:1;
192 - unsigned int mantissa1:32;
193 - unsigned int mantissa0:30;
194 - unsigned int quiet_nan:1;
195 - unsigned int one:1;
199 -#define IEEE854_LONG_DOUBLE_BIAS 0x3fff
203 -#endif /* ieee754.h */
205 Signed-off-by: Robert P. J. Day <rpjday@mindspring.com>