undefined reference to `__lshrdi3' error with GCC 4.0

undefined reference to `__lshrdi3' error with GCC 4.0

[Martin Michlmayr]

Has anyone else seen the following error when compiling a kernel with GCC 4.0
(GCC 3.3 works) and knows what to do about it?

arch/mips/kernel/built-in.o: In function `time_init':
: undefined reference to `__lshrdi3'
arch/mips/kernel/built-in.o: In function `time_init':
: relocation truncated to fit: R_MIPS_26 against `__lshrdi3'

This problem is also reported at
http://sources.redhat.com/ml/crossgcc/2005-11/msg00194.html but no solution is
mentioned.
-- 
Martin Michlmayr
http://www.cyrius.com/

Re: undefined reference to `__lshrdi3' error with GCC 4.0

[P. Christeas]

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On Tuesday 17 January 2006 3:48 pm, Martin Michlmayr wrote:
> Has anyone else seen the following error when compiling a kernel with GCC
> 4.0 (GCC 3.3 works) and knows what to do about it?
>
> arch/mips/kernel/built-in.o: In function `time_init':
> : undefined reference to `__lshrdi3'

I think I've solved it by copying the files
ashldi3.c ashrdi3.c lshrdi3.c
from arch/ppc/lib to arch/mips/lib

The patch for 2.6 is:


[-- Attachment #2: float.patch --]
[-- Type: text/x-diff, Size: 6226 bytes --]

diff --git a/arch/mips/lib/Makefile b/arch/mips/lib/Makefile
index cf12caf..dfa0b12 100644
--- a/arch/mips/lib/Makefile
+++ b/arch/mips/lib/Makefile
@@ -7,4 +7,7 @@ lib-y	+= csum_partial_copy.o memcpy.o pr
 
 obj-y	+= iomap.o
 
+#ugly hack. Why is this needed?
+lib-$(CONFIG_MIKROTIK_RB500) += ashldi3.o ashrdi3.o lshrdi3.o
+
 EXTRA_AFLAGS := $(CFLAGS)
diff --git a/arch/mips/lib/ashldi3.c b/arch/mips/lib/ashldi3.c
new file mode 100644
index 0000000..2f4a3d5
--- /dev/null
+++ b/arch/mips/lib/ashldi3.c
@@ -0,0 +1,66 @@
+/* ashrdi3.c extracted from gcc-2.95.2/libgcc2.c which is: */
+/* Copyright (C) 1989, 92-98, 1999 Free Software Foundation, Inc.
+
+This file is part of GNU CC.
+
+GNU CC 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 2, or (at your option)
+any later version.
+
+GNU CC 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 GNU CC; see the file COPYING.  If not, write to
+the Free Software Foundation, 59 Temple Place - Suite 330,
+Boston, MA 02111-1307, USA.  */
+
+#include <linux/linkage.h>
+#include <linux/module.h>
+#define BITS_PER_UNIT 8
+
+typedef		 int SItype	__attribute__ ((mode (SI)));
+typedef unsigned int USItype	__attribute__ ((mode (SI)));
+typedef		 int DItype	__attribute__ ((mode (DI)));
+typedef int word_type __attribute__ ((mode (__word__)));
+
+struct DIstruct {SItype high, low;};
+
+typedef union
+{
+  struct DIstruct s;
+  DItype ll;
+} DIunion;
+
+DItype
+__ashldi3 (DItype u, word_type b)
+{
+  DIunion w;
+  word_type bm;
+  DIunion uu;
+
+  if (b == 0)
+    return u;
+
+  uu.ll = u;
+
+  bm = (sizeof (SItype) * BITS_PER_UNIT) - b;
+  if (bm <= 0)
+    {
+      w.s.low = 0;
+      w.s.high = (USItype)uu.s.low << -bm;
+    }
+  else
+    {
+      USItype carries = (USItype)uu.s.low >> bm;
+      w.s.low = (USItype)uu.s.low << b;
+      w.s.high = ((USItype)uu.s.high << b) | carries;
+    }
+
+  return w.ll;
+}
+
+EXPORT_SYMBOL(__ashldi3);
diff --git a/arch/mips/lib/ashrdi3.c b/arch/mips/lib/ashrdi3.c
new file mode 100644
index 0000000..eb6d47d
--- /dev/null
+++ b/arch/mips/lib/ashrdi3.c
@@ -0,0 +1,68 @@
+/* ashrdi3.c extracted from gcc-2.7.2/libgcc2.c which is: */
+/* Copyright (C) 1989, 1992, 1993, 1994, 1995 Free Software Foundation, Inc.
+
+This file is part of GNU CC.
+
+GNU CC 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 2, or (at your option)
+any later version.
+
+GNU CC 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 GNU CC; see the file COPYING.  If not, write to
+the Free Software Foundation, 59 Temple Place - Suite 330,
+Boston, MA 02111-1307, USA.  */
+
+#include <linux/linkage.h>
+#include <linux/module.h>
+
+#define BITS_PER_UNIT 8
+
+typedef		 int SItype	__attribute__ ((mode (SI)));
+typedef unsigned int USItype	__attribute__ ((mode (SI)));
+typedef		 int DItype	__attribute__ ((mode (DI)));
+typedef int word_type __attribute__ ((mode (__word__)));
+
+struct DIstruct {SItype high, low;};
+
+typedef union
+{
+  struct DIstruct s;
+  DItype ll;
+} DIunion;
+
+DItype
+__ashrdi3 (DItype u, word_type b)
+{
+  DIunion w;
+  word_type bm;
+  DIunion uu;
+
+  if (b == 0)
+    return u;
+
+  uu.ll = u;
+
+  bm = (sizeof (SItype) * BITS_PER_UNIT) - b;
+  if (bm <= 0)
+    {
+      /* w.s.high = 1..1 or 0..0 */
+      w.s.high = uu.s.high >> (sizeof (SItype) * BITS_PER_UNIT - 1);
+      w.s.low = uu.s.high >> -bm;
+    }
+  else
+    {
+      USItype carries = (USItype)uu.s.high << bm;
+      w.s.high = uu.s.high >> b;
+      w.s.low = ((USItype)uu.s.low >> b) | carries;
+    }
+
+  return w.ll;
+}
+EXPORT_SYMBOL(__ashrdi3);
+
diff --git a/arch/mips/lib/lshrdi3.c b/arch/mips/lib/lshrdi3.c
new file mode 100644
index 0000000..c6a02d5
--- /dev/null
+++ b/arch/mips/lib/lshrdi3.c
@@ -0,0 +1,68 @@
+/* lshrdi3.c extracted from gcc-2.7.2/libgcc2.c which is: */
+/* Copyright (C) 1989, 1992, 1993, 1994, 1995 Free Software Foundation, Inc.
+
+This file is part of GNU CC.
+
+GNU CC 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 2, or (at your option)
+any later version.
+
+GNU CC 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 GNU CC; see the file COPYING.  If not, write to
+the Free Software Foundation, 59 Temple Place - Suite 330,
+Boston, MA 02111-1307, USA.  */
+
+#include <linux/linkage.h>
+#include <linux/module.h>
+
+#define BITS_PER_UNIT 8
+
+typedef		 int SItype	__attribute__ ((mode (SI)));
+typedef unsigned int USItype	__attribute__ ((mode (SI)));
+typedef		 int DItype	__attribute__ ((mode (DI)));
+typedef int word_type __attribute__ ((mode (__word__)));
+
+struct DIstruct {SItype high, low;};
+
+typedef union
+{
+  struct DIstruct s;
+  DItype ll;
+} DIunion;
+
+DItype
+__lshrdi3 (DItype u, word_type b)
+{
+  DIunion w;
+  word_type bm;
+  DIunion uu;
+
+  if (b == 0)
+    return u;
+
+  uu.ll = u;
+
+  bm = (sizeof (SItype) * BITS_PER_UNIT) - b;
+  if (bm <= 0)
+    {
+      w.s.high = 0;
+      w.s.low = (USItype)uu.s.high >> -bm;
+    }
+  else
+    {
+      USItype carries = (USItype)uu.s.high << bm;
+      w.s.high = (USItype)uu.s.high >> b;
+      w.s.low = ((USItype)uu.s.low >> b) | carries;
+    }
+
+  return w.ll;
+}
+
+EXPORT_SYMBOL(__lshrdi3);
+

Re: undefined reference to `__lshrdi3' error with GCC 4.0

[Ralf Baechle]

On Tue, Jan 17, 2006 at 04:17:14PM +0200, P. Christeas wrote:

> On Tuesday 17 January 2006 3:48 pm, Martin Michlmayr wrote:
> > Has anyone else seen the following error when compiling a kernel with GCC
> > 4.0 (GCC 3.3 works) and knows what to do about it?
> >
> > arch/mips/kernel/built-in.o: In function `time_init':
> > : undefined reference to `__lshrdi3'
> 
> I think I've solved it by copying the files
> ashldi3.c ashrdi3.c lshrdi3.c
> from arch/ppc/lib to arch/mips/lib

No such files in arch/ppc/lib?  Oh well, doesn't matter.

> The patch for 2.6 is:

struct DIstruct seems broken for little endian.

  Ralf

Re: undefined reference to `__lshrdi3' error with GCC 4.0

[P. Christeas]

On Tuesday 17 January 2006 5:14 pm, Ralf Baechle wrote:
> On Tue, Jan 17, 2006 at 04:17:14PM +0200, P. Christeas wrote:
> > On Tuesday 17 January 2006 3:48 pm, Martin Michlmayr wrote:
> > > Has anyone else seen the following error when compiling a kernel with
> > > GCC 4.0 (GCC 3.3 works) and knows what to do about it?
> > >
> > > arch/mips/kernel/built-in.o: In function `time_init':
> > > : undefined reference to `__lshrdi3'
> >
> > I think I've solved it by copying the files
> > ashldi3.c ashrdi3.c lshrdi3.c
> > from arch/ppc/lib to arch/mips/lib
>
> No such files in arch/ppc/lib?  Oh well, doesn't matter.
It was from m68k  :S 

>
> > The patch for 2.6 is:
>
> struct DIstruct seems broken for little endian.
What consequences does that have?

>
>   Ralf

Re: undefined reference to `__lshrdi3' error with GCC 4.0

[Ralf Baechle]

On Tue, Jan 17, 2006 at 05:50:20PM +0200, P. Christeas wrote:

> > No such files in arch/ppc/lib?  Oh well, doesn't matter.
> It was from m68k  :S 
> 
> > > The patch for 2.6 is:
> >
> > struct DIstruct seems broken for little endian.
> What consequences does that have?

Wrong results of 64-bit shift operations when building with -Os.

  Ralf

Re: undefined reference to `__lshrdi3' error with GCC 4.0

[Ralf Baechle]

On Tue, Jan 17, 2006 at 04:17:14PM +0200, P. Christeas wrote:

> On Tuesday 17 January 2006 3:48 pm, Martin Michlmayr wrote:
> > Has anyone else seen the following error when compiling a kernel with GCC
> > 4.0 (GCC 3.3 works) and knows what to do about it?
> >
> > arch/mips/kernel/built-in.o: In function `time_init':
> > : undefined reference to `__lshrdi3'

Thanks to Martin Michlmayr's testing I now know this problem is limited
to kernels built with gcc 4.0 and newer when optimizing for size.

> I think I've solved it by copying the files
> ashldi3.c ashrdi3.c lshrdi3.c
> from arch/ppc/lib to arch/mips/lib

There is an awful lot of libgcc bits flying around in the kernel and I guess
I'd be flamed for submitting even more ;-)  so I tried to come up with
something to make most if not all unnecessary.  Still needs a little
polishing but below for testing and commenting.

  Ralf

diff --git a/include/asm-mips/libgcc.h b/include/asm-mips/libgcc.h
new file mode 100644
index 0000000..0aef711
 include/asm-mips/libgcc.h |    8 ++++++++
 include/linux/libgcc.h    |   32 ++++++++++++++++++++++++++++++++
 lib/Makefile              |    1 +
 lib/ashldi3.c             |   32 ++++++++++++++++++++++++++++++++
 lib/ashrdi3.c             |   36 ++++++++++++++++++++++++++++++++++++
 lib/lshrdi3.c             |   34 ++++++++++++++++++++++++++++++++++
 6 files changed, 143 insertions(+)

Index: linux-mips/include/asm-mips/libgcc.h
===================================================================
--- /dev/null
+++ linux-mips/include/asm-mips/libgcc.h
@@ -0,0 +1,8 @@
+#ifndef __ASM_LIBGCC_H
+#define __ASM_LIBGCC_H
+
+#define ARCH_NEEDS_ashldi3
+#define ARCH_NEEDS_ashrdi3
+#define ARCH_NEEDS_lshrdi3
+
+#endif /* __ASM_LIBGCC_H */
Index: linux-mips/include/linux/libgcc.h
===================================================================
--- /dev/null
+++ linux-mips/include/linux/libgcc.h
@@ -0,0 +1,32 @@
+#ifndef __LINUX_LIBGCC_H
+#define __LINUX_LIBGCC_H
+
+#include <asm/byteorder.h>
+#include <asm/libgcc.h>
+
+typedef long long DWtype;
+typedef int Wtype;
+typedef unsigned int UWtype;
+typedef int word_type __attribute__ ((mode (__word__)));
+
+#define BITS_PER_UNIT 8
+
+#ifdef __BIG_ENDIAN
+struct DWstruct {
+	Wtype high, low;
+};
+#elif defined(__LITTLE_ENDIAN)
+struct DWstruct {
+	Wtype low, high;
+};
+#else
+#error I feel sick.
+#endif
+
+typedef union
+{
+	struct DWstruct s;
+	DWtype ll;
+} DWunion;
+
+#endif /* __LINUX_LIBGCC_H */
Index: linux-mips/lib/Makefile
===================================================================
--- linux-mips.orig/lib/Makefile
+++ linux-mips/lib/Makefile
@@ -8,6 +8,7 @@ lib-y := errno.o ctype.o string.o vsprin
 	 sha1.o
 
 lib-y	+= kobject.o kref.o kobject_uevent.o klist.o
+lib-y	+= ashldi3.o ashrdi3.o lshrdi3.o
 
 obj-y += sort.o parser.o halfmd4.o
 
Index: linux-mips/lib/ashldi3.c
===================================================================
--- /dev/null
+++ linux-mips/lib/ashldi3.c
@@ -0,0 +1,32 @@
+#include <linux/libgcc.h>
+#include <linux/module.h>
+
+#ifdef ARCH_NEEDS_ashldi3
+
+DWtype __ashldi3(DWtype u, word_type b)
+{
+	DWunion uu, w;
+	word_type bm;
+
+	if (b == 0)
+		return u;
+
+	uu.ll = u;
+	bm = (sizeof(Wtype) * BITS_PER_UNIT) - b;
+
+	if (bm <= 0) {
+		w.s.low = 0;
+		w.s.high = (UWtype) uu.s.low << -bm;
+	} else {
+		const UWtype carries = (UWtype) uu.s.low >> bm;
+
+		w.s.low = (UWtype) uu.s.low << b;
+		w.s.high = ((UWtype) uu.s.high << b) | carries;
+	}
+
+	return w.ll;
+}
+
+EXPORT_SYMBOL(__ashldi3);
+
+#endif /* ARCH_NEEDS_ashldi3 */
Index: linux-mips/lib/ashrdi3.c
===================================================================
--- /dev/null
+++ linux-mips/lib/ashrdi3.c
@@ -0,0 +1,36 @@
+#include <linux/libgcc.h>
+#include <linux/module.h>
+
+/* Unless shift functions are defined with full ANSI prototypes,
+   parameter b will be promoted to int if word_type is smaller than an int.  */
+#ifdef ARCH_NEEDS_ashrdi3
+
+DWtype __ashrdi3(DWtype u, word_type b)
+{
+	DWunion uu, w;
+	word_type bm;
+
+	if (b == 0)
+		return u;
+
+	uu.ll = u;
+	bm = (sizeof(Wtype) * BITS_PER_UNIT) - b;
+
+	if (bm <= 0) {
+		/* w.s.high = 1..1 or 0..0 */
+		w.s.high =
+		    uu.s.high >> (sizeof(Wtype) * BITS_PER_UNIT - 1);
+		w.s.low = uu.s.high >> -bm;
+	} else {
+		const UWtype carries = (UWtype) uu.s.high << bm;
+
+		w.s.high = uu.s.high >> b;
+		w.s.low = ((UWtype) uu.s.low >> b) | carries;
+	}
+
+	return w.ll;
+}
+
+EXPORT_SYMBOL(__ashrdi3);
+
+#endif /* ARCH_NEEDS_ashrdi3 */
Index: linux-mips/lib/lshrdi3.c
===================================================================
--- /dev/null
+++ linux-mips/lib/lshrdi3.c
@@ -0,0 +1,34 @@
+#include <linux/libgcc.h>
+#include <linux/module.h>
+
+/* Unless shift functions are defined with full ANSI prototypes,
+   parameter b will be promoted to int if word_type is smaller than an int.  */
+#ifdef ARCH_NEEDS_lshrdi3
+
+DWtype __lshrdi3(DWtype u, word_type b)
+{
+	DWunion uu, w;
+	word_type bm;
+
+	if (b == 0)
+		return u;
+
+	uu.ll = u;
+	bm = (sizeof(Wtype) * BITS_PER_UNIT) - b;
+
+	if (bm <= 0) {
+		w.s.high = 0;
+		w.s.low = (UWtype) uu.s.high >> -bm;
+	} else {
+		const UWtype carries = (UWtype) uu.s.high << bm;
+
+		w.s.high = (UWtype) uu.s.high >> b;
+		w.s.low = ((UWtype) uu.s.low >> b) | carries;
+	}
+
+	return w.ll;
+}
+
+EXPORT_SYMBOL(__lshrdi3);
+
+#endif /* ARCH_NEEDS_lshrdi3 */

Re: undefined reference to `__lshrdi3' error with GCC 4.0

[Jan-Benedict Glaw]

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On Tue, 2006-01-17 19:08:59 +0000, Ralf Baechle <ralf@linux-mips.org> wrote:
> There is an awful lot of libgcc bits flying around in the kernel and I guess
> I'd be flamed for submitting even more ;-)  so I tried to come up with
> something to make most if not all unnecessary.  Still needs a little
> polishing but below for testing and commenting.

People will love you for that. I also already added libgcc
functions:-)

> +#ifdef __BIG_ENDIAN
> +struct DWstruct {
> +	Wtype high, low;
> +};
> +#elif defined(__LITTLE_ENDIAN)
> +struct DWstruct {
> +	Wtype low, high;
> +};
> +#else
> +#error I feel sick.
> +#endif

No, you feel PDP11ish. Though you'd put quotes about the warning
message.

I'm all for adding this!

MfG, JBG

-- 
Jan-Benedict Glaw       jbglaw@lug-owl.de    . +49-172-7608481             _ O _
"Eine Freie Meinung in  einem Freien Kopf    | Gegen Zensur | Gegen Krieg  _ _ O
 für einen Freien Staat voll Freier Bürger"  | im Internet! |   im Irak!   O O O
ret = do_actions((curr | FREE_SPEECH) & ~(NEW_COPYRIGHT_LAW | DRM | TCPA));

[-- Attachment #2: Digital signature --]
[-- Type: application/pgp-signature, Size: 189 bytes --]

Re: undefined reference to `__lshrdi3' error with GCC 4.0

[Daniel Jacobowitz]

On Tue, Jan 17, 2006 at 08:38:36PM +0100, Jan-Benedict Glaw wrote:
> > +#else
> > +#error I feel sick.
> > +#endif
> 
> No, you feel PDP11ish. Though you'd put quotes about the warning
> message.

No, you wouldn't.

drow@nevyn:~% echo '#error A B' | gcc -E - 
# 1 "<stdin>"
# 1 "<built-in>"
# 1 "<command line>"
# 1 "<stdin>"
<stdin>:1:2: error: #error A B
drow@nevyn:~% echo '#error "A B"' | gcc -E -
# 1 "<stdin>"
# 1 "<built-in>"
# 1 "<command line>"
# 1 "<stdin>"
<stdin>:1:2: error: #error "A B"
drow@nevyn:~% 

-- 
Daniel Jacobowitz
CodeSourcery

Re: undefined reference to `__lshrdi3' error with GCC 4.0

[Martin Michlmayr]

* Ralf Baechle <ralf@linux-mips.org> [2006-01-17 19:08]:
> > > arch/mips/kernel/built-in.o: In function `time_init':
> > > : undefined reference to `__lshrdi3'
> 
> Thanks to Martin Michlmayr's testing I now know this problem is limited
> to kernels built with gcc 4.0 and newer when optimizing for size.
...
> There is an awful lot of libgcc bits flying around in the kernel and I guess
> I'd be flamed for submitting even more ;-)  so I tried to come up with
> something to make most if not all unnecessary.  Still needs a little
> polishing but below for testing and commenting.

I think you've cleaned it up in the meantime.  Can you please send the
patch to lkml as a RFC?
-- 
Martin Michlmayr
http://www.cyrius.com/