[Qemu-devel] [PATCH] fix warning in syscall.c

[Qemu-devel] [PATCH] fix warning in syscall.c

[Robert Reif]

[-- Attachment #1: Type: text/plain, Size: 269 bytes --]

/home/wine/qemu/linux-user/syscall.c: In function `do_fork':
/home/wine/qemu/linux-user/syscall.c:2790: warning: implicit declaration 
of function `qemu_mallocz'
/home/wine/qemu/linux-user/syscall.c:2790: warning: assignment makes 
pointer from integer without a cast


[-- Attachment #2: syscall.diff.txt --]
[-- Type: text/plain, Size: 222 bytes --]

--- linux-user/syscall.c	(revision 4830)
+++ linux-user/syscall.c	(working copy)
@@ -72,6 +72,7 @@
 #include "linux_loop.h"
 
 #include "qemu.h"
+#include "qemu-common.h"
 
 #if defined(USE_NPTL)
 #include <linux/futex.h>

[Qemu-devel] problem when building arm host

[Cai Qiang]

Hi,
  I am trying to build qemu for arm host. I got below error:

......
make -C i386-linux-user all
make[1]: Entering directory `/media/system/u/SW/src/qemu-arm-host/i386-linux-user'
arm-linux-gcc -g   -Wl,-T,/u/SW/src/qemu-arm-host/arm.ld -o qemu-i386 main.o syscall.o strace.o mmap.o signal.o path.o thunk.o elfload.o linuxload.o uaccess.o vm86.o gdbstub.o libqemu.a ../libqemu_user.a   -lm -lrt -lpthread
libqemu.a(cpu-exec.o): In function `cpu_x86_exec':
/u/SW/src/qemu-arm-host/cpu-exec.c:615: relocation truncated to fit: R_ARM_PC24 against symbol `code_gen_prologue' defined in COMMON section in libqemu.a(exec.o)
/media/system/u/SW/usr/local/arm/gcc-4.0.2-glibc-2.3.5/arm-unknown-linux-gnu/bin/../lib/gcc/arm-unknown-linux-gnu/4.0.2/../../../../arm-unknown-linux-gnu/bin/ld: warning: .preinit_array section has zero size
/media/system/u/SW/usr/local/arm/gcc-4.0.2-glibc-2.3.5/arm-unknown-linux-gnu/bin/../lib/gcc/arm-unknown-linux-gnu/4.0.2/../../../../arm-unknown-linux-gnu/bin/ld: warning: .init_array section has zero size
/media/system/u/SW/usr/local/arm/gcc-4.0.2-glibc-2.3.5/arm-unknown-linux-gnu/bin/../lib/gcc/arm-unknown-linux-gnu/4.0.2/../../../../arm-unknown-linux-gnu/bin/ld: warning: .fini_array section has zero size
collect2: ld returned 1 exit status
make[1]: *** [qemu-i386] Error 1
make[1]: Leaving directory `/media/system/u/SW/src/qemu-arm-host/i386-linux-user'
make: *** [subdir-i386-linux-user] Error 2

in old post of andrzej zaborowski, he said

"Yes, arm-linux-user fails with the same error because gcc doesn't
manage to make the call to code_gen_prologue.  One solution is to wrap
the #define tcg_qemu_tb_exec in tcg/tcg.h in an #ifndef, and override
it tcg/arm/tcg-target.h with the same kind of call as was used before
introduction of prologue/epilogue which was possibly more optimal."

but I don't understand above clearly. What I did is 

in tcg/tcg.h

#ifdef __powerpc__
#define tcg_qemu_tb_exec(tb_ptr) \
    ((long REGPARM __attribute__ ((longcall)) (*)(void *))code_gen_prologue)(tb_ptr)
#else
#ifndef tcg_qemu_tb_exec
#define tcg_qemu_tb_exec(tb_ptr) ((long REGPARM (*)(void *))code_gen_prologue)(tb_ptr)
#endif
#endif

and add  
#ifndef tcg_qemu_tb_exec
#define tcg_qemu_tb_exec(tb_ptr) ((long REGPARM (*)(void *))code_gen_prologue)(tb_ptr)
#endif

in the end of tcg/arm/tcg-target.h

But seems no effect. Did I mis-understand?

In old post Paul also pointed out:

"Or tweak the linker script to place code_gen_prologue near to the code 
segment."

Can anyone teach me how to do this?

Best Regards!

Re: [Qemu-devel] problem when building arm host

[Cai Qiang]

I got it. I added below line
 
  code_gen_prologue = .;

after the 

  .text      :
  {
    *(.text)
    /* .gnu.warning sections are handled specially by elf32.em.  */
    *(.gnu.warning)
    *(.gnu.linkonce.t*)
  } =0x47ff041f

----- Original Message ----- 
From: "Cai Qiang" <caiqiang@ustc.edu>
To: <qemu-devel@nongnu.org>
Sent: Thursday, July 03, 2008 11:49 AM
Subject: [Qemu-devel] problem when building arm host


> Hi,
>  I am trying to build qemu for arm host. I got below error:
> 
> ......
> make -C i386-linux-user all
> make[1]: Entering directory `/media/system/u/SW/src/qemu-arm-host/i386-linux-user'
> arm-linux-gcc -g   -Wl,-T,/u/SW/src/qemu-arm-host/arm.ld -o qemu-i386 main.o syscall.o strace.o mmap.o signal.o path.o thunk.o elfload.o linuxload.o uaccess.o vm86.o gdbstub.o libqemu.a ../libqemu_user.a   -lm -lrt -lpthread
> libqemu.a(cpu-exec.o): In function `cpu_x86_exec':
> /u/SW/src/qemu-arm-host/cpu-exec.c:615: relocation truncated to fit: R_ARM_PC24 against symbol `code_gen_prologue' defined in COMMON section in libqemu.a(exec.o)
> /media/system/u/SW/usr/local/arm/gcc-4.0.2-glibc-2.3.5/arm-unknown-linux-gnu/bin/../lib/gcc/arm-unknown-linux-gnu/4.0.2/../../../../arm-unknown-linux-gnu/bin/ld: warning: .preinit_array section has zero size
> /media/system/u/SW/usr/local/arm/gcc-4.0.2-glibc-2.3.5/arm-unknown-linux-gnu/bin/../lib/gcc/arm-unknown-linux-gnu/4.0.2/../../../../arm-unknown-linux-gnu/bin/ld: warning: .init_array section has zero size
> /media/system/u/SW/usr/local/arm/gcc-4.0.2-glibc-2.3.5/arm-unknown-linux-gnu/bin/../lib/gcc/arm-unknown-linux-gnu/4.0.2/../../../../arm-unknown-linux-gnu/bin/ld: warning: .fini_array section has zero size
> collect2: ld returned 1 exit status
> make[1]: *** [qemu-i386] Error 1
> make[1]: Leaving directory `/media/system/u/SW/src/qemu-arm-host/i386-linux-user'
> make: *** [subdir-i386-linux-user] Error 2
> 
> in old post of andrzej zaborowski, he said
> 
> "Yes, arm-linux-user fails with the same error because gcc doesn't
> manage to make the call to code_gen_prologue.  One solution is to wrap
> the #define tcg_qemu_tb_exec in tcg/tcg.h in an #ifndef, and override
> it tcg/arm/tcg-target.h with the same kind of call as was used before
> introduction of prologue/epilogue which was possibly more optimal."
> 
> but I don't understand above clearly. What I did is 
> 
> in tcg/tcg.h
> 
> #ifdef __powerpc__
> #define tcg_qemu_tb_exec(tb_ptr) \
>    ((long REGPARM __attribute__ ((longcall)) (*)(void *))code_gen_prologue)(tb_ptr)
> #else
> #ifndef tcg_qemu_tb_exec
> #define tcg_qemu_tb_exec(tb_ptr) ((long REGPARM (*)(void *))code_gen_prologue)(tb_ptr)
> #endif
> #endif
> 
> and add  
> #ifndef tcg_qemu_tb_exec
> #define tcg_qemu_tb_exec(tb_ptr) ((long REGPARM (*)(void *))code_gen_prologue)(tb_ptr)
> #endif
> 
> in the end of tcg/arm/tcg-target.h
> 
> But seems no effect. Did I mis-understand?
> 
> In old post Paul also pointed out:
> 
> "Or tweak the linker script to place code_gen_prologue near to the code 
> segment."
> 
> Can anyone teach me how to do this?
> 
> Best Regards!
> 
> 
> 
> 
>