Re: glibc 2.3.2 targeting arm-linux, failed to cross-compile.

[Nick Patavalis]

On Fri, May 16, 2003 at 12:19:02AM -0400, Daniel Jacobowitz wrote:
> On Thu, May 15, 2003 at 08:46:10PM +0300, Nick Patavalis wrote:
> >
> > Finaly, and thanks to your patches, I got glibc 2.3.2 to cross-compile
> > (targeting arm-linux), and I installed it on a target SA1110-based
> > system. Test binaries I have created seem to run. That is, until they
> > issue the "connect" system call, at which point everything
> > segfaults. The following test program, for example, crashes reliably:
> 
> Yes.  I recommend reading the archives of this list; you'll find
> another patch I posted to fix this problem.  It was about a month ago
> now.
> 

I managed to cross-build, what appears to be, a working glibc-2.3.2
targeting arm-linux. Here are---all in all---the patches I applied,
starting from the distributed 2.3.2 sources:

  PATCH 0: Semicolon at the end of "ENTRY"

diff -urN glibc-2.3.2/linuxthreads/sysdeps/unix/sysv/linux/arm/sysdep-cancel.h 
glibc-2.3.2-sysdep_cancel/linuxthreads/sysdeps/unix/sysv/linux/arm/sysdep-cancel.h
--- glibc-2.3.2/linuxthreads/sysdeps/unix/sysv/linux/arm/sysdep-cancel.h        
Sun Jan 12 11:13:57 2003
+++ 
glibc-2.3.2-sysdep_cancel/linuxthreads/sysdeps/unix/sysv/linux/arm/sysdep-cancel.h
  Wed May 14 14:16:49 2003
@@ -34,7 +34,7 @@
 # define PSEUDO(name, syscall_name, args)                              \
   .section ".text";                                                    \
     PSEUDO_PROLOGUE;                                                   \
-  ENTRY (name)                                                         \
+  ENTRY (name);                                                                
\
     SINGLE_THREAD_P_INT;                                               \
     bne .Lpseudo_cancel;                                               \
     DO_CALL (syscall_name, args);                                      \

  PATCH 1: Replace "lr" with "reg"

diff -urN glibc-2.3.2/linuxthreads/sysdeps/unix/sysv/linux/arm/sysdep-cancel.h 
glibc-2.3.2-sysdep-cancel-lr/linuxthreads/sysdeps/unix/sysv/linux/arm/sysdep-cancel.h
--- glibc-2.3.2/linuxthreads/sysdeps/unix/sysv/linux/arm/sysdep-cancel.h        
Sun Jan 12 11:13:57 2003
+++ 
glibc-2.3.2-sysdep-cancel-lr/linuxthreads/sysdeps/unix/sysv/linux/arm/sysdep-cancel.h
       Mon May 19 14:17:49 2003
@@ -110,7 +110,7 @@
   ldr reg, 2b;                                                         \
 3:                                                                     \
   add ip, pc, ip;                                                      \
-  ldr ip, [ip, lr];                                                    \
+  ldr ip, [ip, reg];                                                   \
   teq ip, #0;
 #   define SINGLE_THREAD_P_INT                                         \
   str lr, [sp, $-4]!;                                                  \

  PATCH 2: Reworked doargs

diff -urN glibc-2.3.2/linuxthreads/sysdeps/unix/sysv/linux/arm/sysdep-cancel.h 
glibc-2.3.2-sysdep-cancel-doargs/linuxthreads/sysdeps/unix/sysv/linux/arm/sysdep-cancel.h
--- glibc-2.3.2/linuxthreads/sysdeps/unix/sysv/linux/arm/sysdep-cancel.h        
Mon May 19 14:23:32 2003
+++ 
glibc-2.3.2-sysdep-cancel-doargs/linuxthreads/sysdeps/unix/sysv/linux/arm/sysdep-cancel.h
   Mon May 19 14:24:55 2003
@@ -24,6 +24,15 @@
 
 #if !defined NOT_IN_libc || defined IS_IN_libpthread
 
+/* We push lr onto the stack, so we have to use ldmib instead of ldmia
+   to find the saved arguments.  */
+#undef DOARGS_5
+#undef DOARGS_6
+#undef DOARGS_7
+#define DOARGS_5 str r4, [sp, $-4]!; ldr r4, [sp, $8];
+#define DOARGS_6 mov ip, sp; stmfd sp!, {r4, r5}; ldmib ip, {r4, r5};
+#define DOARGS_7 mov ip, sp; stmfd sp!, {r4, r5, r6}; ldmib ip, {r4, r5, r6};
+
 # undef PSEUDO_RET
 # define PSEUDO_RET                                                    \
     ldrcc pc, [sp], $4;                                                        
\

Finally, I had to remove the "*** BUG in glibc/" line from "libc.so"
and "libpthreads.so", after building the library.

I used:

  GCC-3.2.3 (cross configuration hosted on i386, targeting arm-linux)
  BINUTILS-2.13.2 (cross config hosted on i386, targeting arm-linux)
  Kernel headers from 2.4.18-rmk7

My only problem is that modules (even trivial ones) compiled with
GCC-3.2.3 fail to work when inserted in a 2.4.18-rmk7 kernel (kernel
is compiled using 2.95.3). I know that this is a compiler issue and
has nothing to do with "glibc", but do you happen to know if this
behavior is expected?

/npat

P.S. As far as I've searched the mailing-lists there seem to be no
other relevant patches (i.e. patches required to cross-compile a
stable glibc-2.3.2 targeting ARM). If you know differently, please
drop a line.

-- 
We shall not cease from exploration, and the end of all our exploring
will be to arrive where we started and know the place for the first
time.
  -- T.S. Elliot