risc-v: 0.383
user-level: 0.370
TCG: 0.354
mistranslation: 0.324
VMM: 0.305
hypervisor: 0.302
x86: 0.288
ppc: 0.287
virtual: 0.283
i386: 0.271
register: 0.270
KVM: 0.263
debug: 0.261
graphic: 0.260
architecture: 0.257
device: 0.250
permissions: 0.250
peripherals: 0.248
kernel: 0.248
files: 0.243
PID: 0.240
boot: 0.239
vnc: 0.238
assembly: 0.234
arm: 0.234
performance: 0.233
semantic: 0.232
socket: 0.228
network: 0.226

QEMU fails to build on CentOS 5.10 with relocation R_X86_64_PC32 error

  lt LINK libcacard.la
/usr/bin/ld: libcacard/.libs/vcard.o: relocation R_X86_64_PC32 against `vcard_buffer_response_delete' can not be used when making a shared object; recompile with -fPIC
/usr/bin/ld: final link failed: Bad value
collect2: ld returned 1 exit status
make[4]: *** [libcacard.la] Error 1
make[3]: *** [subdir-libcacard] Error 2

I have bisect'd this to:

dcs-xen-53:~/qemu>git-bisect next
00c705fb92bc6e69e955aeac3614e05ca02feacd is the first bad commit
commit 00c705fb92bc6e69e955aeac3614e05ca02feacd
Author: Paolo Bonzini <email address hidden>
Date:   Tue May 29 11:40:24 2012 +0200

    build: libcacard Makefile cleanups
    
    Build vscclient from toplevel Makefile, limit usage of vpath.
    
    Signed-off-by: Paolo Bonzini <email address hidden>

:100644 100644 a10005a22fe44a107dfec15106960612b43be71f 1d34b9539e9ba47fdb7028ad0569389fa48712b9 M      Makefile
:100644 100644 ae3770a5f718742838844f9064be6a7153ac7469 74110dda7e38b8ddae47a53ad4cb6ecf48231fa0 M      Makefile.objs
:100644 100644 3dfdf925fdc2c92239b7053a3d4e09687dcc2171 555894db4aa717f15cfc24093d838131f422fc78 M      Makefile.target
:100755 100755 e50ad0bb8fc2e331562f3c09e605af6597a143b1 cd5e8b349c137f621d2e9dc516145bc650d977c0 M      configure
:040000 040000 160d565b7e551c3248333c9e49f34edb7a30f5e0 008bc3fccda52f78accf9494539ba62bfb1621a0 M      libcacard

dcs-xen-53:~/qemu>git bisect log   
git bisect start
# bad: [7457fe9541b5162f285454947448d553a5d5a531] Update version for v1.7.0-rc2 release
git bisect bad 7457fe9541b5162f285454947448d553a5d5a531
# good: [ed7ec8400707fe42f4a0f40db2f2d5827ecea789] Merge remote-tracking branch 'bonzini/scsi.2' into staging
git bisect good ed7ec8400707fe42f4a0f40db2f2d5827ecea789
# bad: [1d31fca470648ec66afd8743491bfb5846306341] qemu-barrier: Fix compilation on i386 hosts
git bisect bad 1d31fca470648ec66afd8743491bfb5846306341
# good: [9de36b1a7cf61aa8be365f13c81668b3e19fbc7f] Make -machine/-enable-kvm options merge into a single list
git bisect good 9de36b1a7cf61aa8be365f13c81668b3e19fbc7f
# bad: [3edb8f92e8b5f18797693d8ed9fad3962e11e25d] target-s390x: Pass S390CPU to s390_cpu_restart()
git bisect bad 3edb8f92e8b5f18797693d8ed9fad3962e11e25d
# good: [aecff6924dab0197b6c8f132e44502b25fd98a38] hw/arm_gic: Make gic_reset a sysbus reset function
git bisect good aecff6924dab0197b6c8f132e44502b25fd98a38
# good: [b9531b6eed93c9e1769d6f371c4da5d1f955e0d1] block/qcow2: Add missing GCC_FMT_ATTR to function report_unsupported()
git bisect good b9531b6eed93c9e1769d6f371c4da5d1f955e0d1
# good: [dd86df756e02b684718dd5378725927361b0ad36] Merge remote-tracking branch 'sstabellini/for_1.1_rc3' into staging
git bisect good dd86df756e02b684718dd5378725927361b0ad36
# good: [8ebdf9dcc6036171a9f8bac3fe8dc459725a3e83] sun4u: Use cpu_sparc_init() to obtain SPARCCPU
git bisect good 8ebdf9dcc6036171a9f8bac3fe8dc459725a3e83
# good: [8867aef02e1e5817c72b2e09be4ae952eb0c9d9d] build: move ui/ objects to nested Makefile.objs
git bisect good 8867aef02e1e5817c72b2e09be4ae952eb0c9d9d
# bad: [e8de1ea849176812765bf30514f66c5450a1edc6] target-xtensa: add attributes to helper functions
git bisect bad e8de1ea849176812765bf30514f66c5450a1edc6
# bad: [fa79c914efd35cb60e0bc18512c03690c48b13e2] Merge remote-tracking branch 'bonzini/nested-makefiles-3' into staging
git bisect bad fa79c914efd35cb60e0bc18512c03690c48b13e2
# good: [c353f261946ddbd814b333ae2440712b486977fd] build: move per-target hw/ objects to nested Makefile.objs
git bisect good c353f261946ddbd814b333ae2440712b486977fd
# bad: [25f27a4f7160d077d6992e811021b4bc3a82abc1] build: compile oslib-obj-y once
git bisect bad 25f27a4f7160d077d6992e811021b4bc3a82abc1
# bad: [00c705fb92bc6e69e955aeac3614e05ca02feacd] build: libcacard Makefile cleanups
git bisect bad 00c705fb92bc6e69e955aeac3614e05ca02feacd
# good: [49ac9e0a8cfb737d6da9c0b056c062e3dec0ba45] build: move device tree to per-target Makefile.objs
git bisect good 49ac9e0a8cfb737d6da9c0b056c062e3dec0ba45

On 12/03/13 09:06, Paolo Bonzini wrote:
> Il 03/12/2013 14:25, Stefano Stabellini ha scritto:
>> CC'ing Paolo and xen-devel.
>> The original thread is here:
>>
>> http://marc.info/?l=xen-devel&m=135718999710640
>>
>> On Mon, 2 Dec 2013, Don Slutz wrote:
>>>> Public bug reported:
>>>>
>>>>    lt LINK libcacard.la
>>>> /usr/bin/ld: libcacard/.libs/vcard.o: relocation R_X86_64_PC32 against `vcard_buffer_response_delete' can not be used when making a shared object; recompile with -fPIC
>>>> /usr/bin/ld: final link failed: Bad value
>>>> collect2: ld returned 1 exit status
>>>> make[4]: *** [libcacard.la] Error 1
>>>> make[3]: *** [subdir-libcacard] Error 2
> Thanks, I'll try to reproduce.  Please send the "make V=1" output for a
> full build in the meanwhile.
Here it is for a full build of:

* 7dc65c0 (HEAD, origin/master, origin/HEAD, master) Open 2.0 
development tree

   -Don Slutz
> Paolo



On 12/03/13 12:15, Paolo Bonzini wrote:
> Il 03/12/2013 14:25, Stefano Stabellini ha scritto:
>> CC'ing Paolo and xen-devel.
>> The original thread is here:
>>
>> http://marc.info/?l=xen-devel&m=135718999710640
>>
>> On Mon, 2 Dec 2013, Don Slutz wrote:
>>> Public bug reported:
>>>
>>>    lt LINK libcacard.la
>>> /usr/bin/ld: libcacard/.libs/vcard.o: relocation R_X86_64_PC32 against `vcard_buffer_response_delete' can not be used when making a shared object; recompile with -fPIC
>>> /usr/bin/ld: final link failed: Bad value
>>> collect2: ld returned 1 exit status
>>> make[4]: *** [libcacard.la] Error 1
>>> make[3]: *** [subdir-libcacard] Error 2
> This is a bug in RHEL5 binutils.  Configure with --disable-pie to work
> around it.
Any hints or pointers about the bug in RHEL5 binutils?  I can try and 
make a patch to auto detect this.

That still fails for (7dc65c0 (HEAD, origin/master, origin/HEAD, master) 
Open 2.0 development tree):

...
libtool  --mode=link --tag=CC cc -m64 -D_GNU_SOURCE 
-D_FILE_OFFSET_BITS=64 -D_LARGEFILE_SOURCE -Wstrict-prototypes 
-Wredundant-decls -Wall -Wundef -Wwrite-strings -Wmissing-prototypes 
-fno-strict-aliasing  -Wendif-labels -Wmissing-include-dirs 
-Wnested-externs -Wformat-security -Wformat-y2k -Winit-self 
-Wold-style-definition -fstack-protector-all -I/usr/include/libpng12   
-I/usr/include/nss3 -I/usr/include/nspr4 -pthread 
-I/usr/include/glib-2.0 -I/usr/lib64/glib-2.0/include 
-I/usr/include/pixman-1   -I/home/don/qemu/dtc/libfdt -pthread 
-I/usr/include/glib-2.0 -I/usr/lib64/glib-2.0/include 
-I/home/don/qemu/tests -O2 -U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=2 -g 
-Wl,--warn-common -m64 -g  -o vscclient libcacard/vscclient.o 
libcacard.la  -Wc,-fstack-protector-all -lrt -pthread -L/lib64 
-lgthread-2.0 -lglib-2.0    -lz -L/usr/kerberos/lib64 -lcurl -ldl 
-lgssapi_krb5 -lkrb5 -lk5crypto -lcom_err -lidn -lssl -lcrypto -lz -luuid
cc -m64 -D_GNU_SOURCE -D_FILE_OFFSET_BITS=64 -D_LARGEFILE_SOURCE 
-Wstrict-prototypes -Wredundant-decls -Wall -Wundef -Wwrite-strings 
-Wmissing-prototypes -fno-strict-aliasing -Wendif-labels 
-Wmissing-include-dirs -Wnested-externs -Wformat-security -Wformat-y2k 
-Winit-self -Wold-style-definition -fstack-protector-all 
-I/usr/include/libpng12 -I/usr/include/nss3 -I/usr/include/nspr4 
-pthread -I/usr/include/glib-2.0 -I/usr/lib64/glib-2.0/include 
-I/usr/include/pixman-1 -I/home/don/qemu/dtc/libfdt -pthread 
-I/usr/include/glib-2.0 -I/usr/lib64/glib-2.0/include 
-I/home/don/qemu/tests -O2 -U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=2 -g 
-Wl,--warn-common -m64 -g -o .libs/vscclient libcacard/vscclient.o 
-Wl,-fstack-protector-all -pthread  ./.libs/libcacard.so -L/lib64 
-L/usr/kerberos/lib64 -lssl3 -lsmime3 -lnss3 -lnssutil3 -lplds4 -lplc4 
-lnspr4 -lpthread -lrt -lgthread-2.0 -lglib-2.0 -lcurl -ldl 
-lgssapi_krb5 -lkrb5 -lk5crypto -lcom_err -lidn -lssl -lcrypto -lz 
-luuid  -Wl,--rpath -Wl,/usr/local/lib
/usr/bin/ld: -f may not be used without -shared
collect2: ld returned 1 exit status
make: *** [vscclient] Error 1

Attached is the full "make V=1" output.

Here is the configure output:

dcs-xen-53:~/qemu>rm -rf out/tmp;mkdir out/tmp;pushd 
out/tmp;../../configure --disable-pie;make V=1 1>zz1 2>&1;popd
~/qemu/out/tmp ~/qemu
Install prefix    /usr/local
BIOS directory    /usr/local/share/qemu
binary directory  /usr/local/bin
library directory /usr/local/lib
libexec directory /usr/local/libexec
include directory /usr/local/include
config directory  /usr/local/etc
local state directory   /usr/local/var
Manual directory  /usr/local/share/man
ELF interp prefix /usr/gnemul/qemu-%M
Source path       /home/don/qemu
C compiler        cc
Host C compiler   cc
C++ compiler      c++
Objective-C compiler cc
ARFLAGS           rv
CFLAGS            -O2 -U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=2 -g
QEMU_CFLAGS       -m64 -D_GNU_SOURCE -D_FILE_OFFSET_BITS=64 
-D_LARGEFILE_SOURCE -Wstrict-prototypes -Wredundant-decls -Wall -Wundef 
-Wwrite-strings -Wmissing-prototypes -fno-strict-aliasing -Wendif-labels 
-Wmissing-include-dirs -Wnested-externs -Wformat-security -Wformat-y2k 
-Winit-self -Wold-style-definition -fstack-protector-all   
-I/usr/include/libpng12 -I/usr/include/nss3 -I/usr/include/nspr4   
-pthread -I/usr/include/glib-2.0 -I/usr/lib64/glib-2.0/include 
-I/usr/include/pixman-1   -I$(SRC_PATH)/dtc/libfdt
LDFLAGS           -Wl,--warn-common -m64 -g
make              make
install           install
python            python
smbd              /usr/sbin/smbd
host CPU          x86_64
host big endian   no
target list        alpha-softmmu arm-softmmu cris-softmmu i386-softmmu 
lm32-softmmu m68k-softmmu microblaze-softmmu microblazeel-softmmu 
mips-softmmu mips64-softmmu mips64el-softmmu mipsel-softmmu 
moxie-softmmu or32-softmmu ppc-softmmu ppc64-softmmu ppcemb-softmmu 
s390x-softmmu sh4-softmmu sh4eb-softmmu sparc-softmmu sparc64-softmmu 
unicore32-softmmu x86_64-softmmu xtensa-softmmu xtensaeb-softmmu 
alpha-linux-user arm-linux-user armeb-linux-user cris-linux-user 
i386-linux-user m68k-linux-user microblaze-linux-user 
microblazeel-linux-user mips-linux-user mips64-linux-user 
mips64el-linux-user mipsel-linux-user mipsn32-linux-user 
mipsn32el-linux-user or32-linux-user ppc-linux-user ppc64-linux-user 
ppc64abi32-linux-user s390x-linux-user sh4-linux-user sh4eb-linux-user 
sparc-linux-user sparc32plus-linux-user sparc64-linux-user 
unicore32-linux-user x86_64-linux-user
tcg debug enabled no
gprof enabled     no
sparse enabled    no
strip binaries    yes
profiler          no
static build      no
-Werror enabled   no
pixman            system
SDL support       yes
GTK support       no
curses support    yes
curl support      yes
mingw32 support   no
Audio drivers     oss
Block whitelist (rw)
Block whitelist (ro)
VirtFS support    yes
VNC support       yes
VNC TLS support   no
VNC SASL support  yes
VNC JPEG support  yes
VNC PNG support   yes
VNC WS support    no
xen support       yes
brlapi support    no
bluez  support    no
Documentation     yes
GUEST_BASE        yes
PIE               no
vde support       no
Linux AIO support no
ATTR/XATTR support yes
Install blobs     yes
KVM support       yes
RDMA support      no
TCG interpreter   no
fdt support       yes
preadv support    no
fdatasync         yes
madvise           yes
posix_madvise     yes
sigev_thread_id   yes
uuid support      yes
libcap-ng support no
vhost-net support yes
vhost-scsi support yes
Trace backend     nop
Trace output file trace-<pid>
spice support     no (/)
rbd support       no
xfsctl support    no
nss used          yes
libusb            no
usb net redir     no
GLX support       yes
libiscsi support  no
build guest agent yes
QGA VSS support   no
seccomp support   no
coroutine backend ucontext
coroutine pool    yes
GlusterFS support no
virtio-blk-data-plane no
gcov              gcov
gcov enabled      no
TPM support       no
libssh2 support   no
TPM passthrough   no
QOM debugging     yes
vhdx              yes

I bisect'd this to:

dcs-xen-53:~/qemu>git-bisect good
37746c5eacf309fa019ea0fa45f776c36c561457 is the first bad commit
commit 37746c5eacf309fa019ea0fa45f776c36c561457
Author: Marc-André Lureau <email address hidden>
Date:   Mon Feb 25 23:31:12 2013 +0100

     build-sys: must link with -fstack-protector

     It is needed to give that flag to the linker as well, but latest
     libtool 2.4.2 still swallows that argument, so let's pass it with
     libtool -Wc argument.

     qemu-1.4.0/stubs/arch-query-cpu-def.c:6: undefined reference to 
`__stack_chk_guard'

     Signed-off-by: Marc-André Lureau <email address hidden>
     Reviewed-by: Alon Levy <email address hidden>

:100755 100755 33d3354ea30838694020660f5822f551293d7e9a 
ee2e7e8ad9b8a23af96e4e404e3f7658efcbe74b M      configure
:100644 100644 edc2552f0886c99608b97f85bd932460fa50da73 
36aba2de1fa9e0f8acde7640818e94a28dd03c80 M      rules.mak

Do you want a bug opened for this?

    -Don Slutz

> Paolo



On 12/05/13 10:18, Paolo Bonzini wrote:
> Il 04/12/2013 02:32, Don Slutz ha scritto:
>> Any hints or pointers about the bug in RHEL5 binutils?  I can try and
>> make a patch to auto detect this.
> Actually it's RHEL5 GCC:
>
> $ cat f.c
> void *
> f(unsigned char *buf, int len)
> {
>      return (void*)0L;
> }
>
>
> void *
> g(unsigned char *buf, int len)
> {
>      return f(buf, len);
> }
> $ gcc -shared -o f.so f.c -fPIE -fPIC
> /usr/bin/ld: /tmp/ccQc9els.o: relocation R_X86_64_PC32 against `f' can not be used when making a shared object; recompile with -fPIC
> /usr/bin/ld: final link failed: Bad value
> collect2: ld returned 1 exit status
>
>
> The bug is simply that "-fPIE -fPIC" counts as -fPIE rather than -fPIC:
>
> $ gcc -S -o - f.c -fPIE |grep call
> 	call	f                      # PC32 relocation
> $ gcc -S -o - f.c -fPIC |grep call
> 	call	f@PLT                  # PLT32 relocation
>
> On RHEL5:
> $ gcc -S -o - f.c -fPIE -fPIC |grep call
> 	call	f
>
> On RHEL6:
> $ gcc -S -o - f.c -fPIE -fPIC |grep call
> 	call	f@PLT
>
> Paolo
How about this as a patch:

 From 282fba086186ff3b8e2b2b15e647df2b58d082dd Mon Sep 17 00:00:00 2001
From: Don Slutz <email address hidden>
Date: Thu, 5 Dec 2013 18:50:18 +0000
Subject: [PATCH] configure: Auto disabling of PIE due to broken toolchain
  support (bug #1257099)

See https://bugs.launchpad.net/bugs/1257099

On RHEL5 GCC, you can get 'relocation R_X86_64_PC32' errors from ld.
So disable PIE is this is true.

Signed-off-by: Don Slutz <email address hidden>
---
  configure | 43 +++++++++++++++++++++++++++++++++++--------
  1 file changed, 35 insertions(+), 8 deletions(-)

diff --git a/configure b/configure
index cf8123b..a51a9dd 100755
--- a/configure
+++ b/configure
@@ -1339,23 +1339,50 @@ if test "$pie" != "no" ; then
  #  define THREAD
  #endif

+void *f(unsigned char *buf, int len);
+void *g(unsigned char *buf, int len);
+
+void *
+f(unsigned char *buf, int len)
+{
+    return (void*)0L;
+}
+
+
+void *
+g(unsigned char *buf, int len)
+{
+    return f(buf, len);
+}
+
+#ifdef PIE
  static THREAD int tls_var;

  int main(void) { return tls_var; }
+#endif

  EOF
-  if compile_prog "-fPIE -DPIE" "-pie"; then
-    QEMU_CFLAGS="-fPIE -DPIE $QEMU_CFLAGS"
-    LDFLAGS="-pie $LDFLAGS"
-    pie="yes"
-    if compile_prog "" "-Wl,-z,relro -Wl,-z,now" ; then
-      LDFLAGS="-Wl,-z,relro -Wl,-z,now $LDFLAGS"
+  if compile_prog "-shared -fPIE -fPIC" ""; then
+    if compile_prog "-fPIE -DPIE" "-pie"; then
+      QEMU_CFLAGS="-fPIE -DPIE $QEMU_CFLAGS"
+      LDFLAGS="-pie $LDFLAGS"
+      pie="yes"
+      if compile_prog "" "-Wl,-z,relro -Wl,-z,now" ; then
+        LDFLAGS="-Wl,-z,relro -Wl,-z,now $LDFLAGS"
+      fi
+    else
+      if test "$pie" = "yes"; then
+        error_exit "PIE not available due to missing toolchain support"
+      else
+        echo "Disabling PIE due to missing toolchain support"
+        pie="no"
+      fi
      fi
    else
      if test "$pie" = "yes"; then
-      error_exit "PIE not available due to missing toolchain support"
+      error_exit "PIE not available due to broken toolchain support"
      else
-      echo "Disabling PIE due to missing toolchain support"
+      echo "Disabling PIE due to broken toolchain support"
        pie="no"
      fi
    fi
-- 
1.8.2.1



On 12/06/2013 04:18 AM, Paolo Bonzini wrote:
> $ gcc -shared -o f.so f.c -fPIE -fPIC
> /usr/bin/ld: /tmp/ccQc9els.o: relocation R_X86_64_PC32 against `f' can not be used when making a shared object; recompile with -fPIC
> /usr/bin/ld: final link failed: Bad value
> collect2: ld returned 1 exit status
> 
> 
> The bug is simply that "-fPIE -fPIC" counts as -fPIE rather than -fPIC:
> 
> $ gcc -S -o - f.c -fPIE |grep call
> 	call	f                      # PC32 relocation
> $ gcc -S -o - f.c -fPIC |grep call
> 	call	f@PLT                  # PLT32 relocation

The easy workaround is to drop -fPIE when we're adding -fPIC.


r~


On 12/05/13 16:24, Richard Henderson wrote:
> On 12/06/2013 04:18 AM, Paolo Bonzini wrote:
>> $ gcc -shared -o f.so f.c -fPIE -fPIC
>> /usr/bin/ld: /tmp/ccQc9els.o: relocation R_X86_64_PC32 against `f' can not be used when making a shared object; recompile with -fPIC
>> /usr/bin/ld: final link failed: Bad value
>> collect2: ld returned 1 exit status
>>
>>
>> The bug is simply that "-fPIE -fPIC" counts as -fPIE rather than -fPIC:
>>
>> $ gcc -S -o - f.c -fPIE |grep call
>> 	call	f                      # PC32 relocation
>> $ gcc -S -o - f.c -fPIC |grep call
>> 	call	f@PLT                  # PLT32 relocation
> The easy workaround is to drop -fPIE when we're adding -fPIC.
>
>
> r~
Here is a possible patch based on this statement:

 From 6e57382c58fa1b9be0fe9db8f35f53a7a7858ccd Mon Sep 17 00:00:00 2001
From: Don Slutz <email address hidden>
Date: Fri, 6 Dec 2013 03:12:12 +0000
Subject: [PATCH] configure: Auto disabling of libtool due to broken 
toolchain
  support (bug #1257099)

See https://bugs.launchpad.net/bugs/1257099

On RHEL5 GCC with libtool and PIE, you get 'relocation R_X86_64_PC32' 
errors from ld.
So disable libtool which disables smartcard-nss (aka nss) if this is true.

Signed-off-by: Don Slutz <email address hidden>
---
  configure | 27 +++++++++++++++++++++++++++
  1 file changed, 27 insertions(+)

diff --git a/configure b/configure
index 0666228..5e34095 100755
--- a/configure
+++ b/configure
@@ -1310,6 +1310,33 @@ if compile_prog "-Werror -fno-gcse" "" ; then
    TRANSLATE_OPT_CFLAGS=-fno-gcse
  fi

+# check for broken GCC in RHEL5 with PIE
+if test -n "$libtool" -a "$pie" = "" ; then
+  cat > $TMPC << EOF
+
+void *f(unsigned char *buf, int len);
+void *g(unsigned char *buf, int len);
+
+void *
+f(unsigned char *buf, int len)
+{
+    return (void*)0L;
+}
+
+void *
+g(unsigned char *buf, int len)
+{
+    return f(buf, len);
+}
+
+EOF
+  if ! compile_prog "-shared -fPIE -fPIC" ""; then
+    echo "Disabling libtool due to broken toolchain support"
+    echo "Defaulting to --disable-smartcard-nss"
+    libtool=
+  fi
+fi
+
  if test "$static" = "yes" ; then
    if test "$pie" = "yes" ; then
      error_exit "static and pie are mutually incompatible"
-- 
1.8.2.1

   -Don Slutz


On 12/05/13 10:18, Paolo Bonzini wrote:
> Il 04/12/2013 02:32, Don Slutz ha scritto:
>> Any hints or pointers about the bug in RHEL5 binutils?  I can try and
>> make a patch to auto detect this.
> Actually it's RHEL5 GCC:
>
> $ cat f.c
> void *
> f(unsigned char *buf, int len)
> {
>      return (void*)0L;
> }
>
>
> void *
> g(unsigned char *buf, int len)
> {
>      return f(buf, len);
> }
> $ gcc -shared -o f.so f.c -fPIE -fPIC
> /usr/bin/ld: /tmp/ccQc9els.o: relocation R_X86_64_PC32 against `f' can not be used when making a shared object; recompile with -fPIC
> /usr/bin/ld: final link failed: Bad value
> collect2: ld returned 1 exit status
>
>
> The bug is simply that "-fPIE -fPIC" counts as -fPIE rather than -fPIC:
>
> $ gcc -S -o - f.c -fPIE |grep call
> 	call	f                      # PC32 relocation
> $ gcc -S -o - f.c -fPIC |grep call
> 	call	f@PLT                  # PLT32 relocation
>
> On RHEL5:
> $ gcc -S -o - f.c -fPIE -fPIC |grep call
> 	call	f
>
> On RHEL6:
> $ gcc -S -o - f.c -fPIE -fPIC |grep call
> 	call	f@PLT
>
> Paolo
RHEL5 also "works" if you add -pie:

dcs-xen-53:~/tmp>gcc -shared -o f.so f.c -fPIE -fPIC
/usr/bin/ld: /tmp/cc6pp1n2.o: relocation R_X86_64_PC32 against `f' can 
not be used when making a shared object; recompile with -fPIC
/usr/bin/ld: final link failed: Bad value
collect2: ld returned 1 exit status
dcs-xen-53:~/tmp>gcc -shared -o f.so f.c -fPIE -fPIC -pie
dcs-xen-53:~/tmp>gcc -S -o - f.c -fPIE -pie|grep call
         call    f

I have not figured out a way to take advantage of this.

I just checked and Fedora 17 has the same issue with gcc:
FC17:
dcs-xen-52:~/tmp>gcc -S -o - f.c -fPIE -fPIC |grep call
         call    f
dcs-xen-52:~/tmp>gcc -shared -o f.so f.c -fPIE -fPIC
/usr/bin/ld: /tmp/ccUlVgMP.o: relocation R_X86_64_PC32 against symbol 
`f' can not be used when making a shared object; recompile with -fPIC
/usr/bin/ld: final link failed: Bad value
collect2: error: ld returned 1 exit status

However QEMU builds just fine.  So it is looking like libtool is also 
part of the problem.

    -Don Slutz


On 12/05/13 22:20, Don Slutz wrote:
> On 12/05/13 16:24, Richard Henderson wrote:
>> On 12/06/2013 04:18 AM, Paolo Bonzini wrote:
>>> $ gcc -shared -o f.so f.c -fPIE -fPIC
>>> /usr/bin/ld: /tmp/ccQc9els.o: relocation R_X86_64_PC32 against `f' 
>>> can not be used when making a shared object; recompile with -fPIC
>>> /usr/bin/ld: final link failed: Bad value
>>> collect2: ld returned 1 exit status
>>>
>>>
>>> The bug is simply that "-fPIE -fPIC" counts as -fPIE rather than -fPIC:
>>>
>>> $ gcc -S -o - f.c -fPIE |grep call
>>>     call    f                      # PC32 relocation
>>> $ gcc -S -o - f.c -fPIC |grep call
>>>     call    f@PLT                  # PLT32 relocation
>> The easy workaround is to drop -fPIE when we're adding -fPIC.
>>
>>
>> r~
[snip]

Attached is a much better version.  It drops -fPIE and adds -fPIC for 
libtool.

    -Don Slutz


On 12/09/13 08:22, Paolo Bonzini wrote:
> Il 09/12/2013 13:47, Don Slutz ha scritto:
>> On 12/05/13 22:20, Don Slutz wrote:
>>> On 12/05/13 16:24, Richard Henderson wrote:
>>>> On 12/06/2013 04:18 AM, Paolo Bonzini wrote:
>>>>> $ gcc -shared -o f.so f.c -fPIE -fPIC
>>>>> /usr/bin/ld: /tmp/ccQc9els.o: relocation R_X86_64_PC32 against `f'
>>>>> can not be used when making a shared object; recompile with -fPIC
>>>>> /usr/bin/ld: final link failed: Bad value
>>>>> collect2: ld returned 1 exit status
>>>>>
>>>>>
>>>>> The bug is simply that "-fPIE -fPIC" counts as -fPIE rather than -fPIC:
>>>>>
>>>>> $ gcc -S -o - f.c -fPIE |grep call
>>>>>      call    f                      # PC32 relocation
>>>>> $ gcc -S -o - f.c -fPIC |grep call
>>>>>      call    f@PLT                  # PLT32 relocation
>>>> The easy workaround is to drop -fPIE when we're adding -fPIC.
>>>>
>>>>
>>>> r~
>> [snip]
>>
>> Attached is a much better version.  It drops -fPIE and adds -fPIC for
>> libtool.
> It's not much better, because using position-independent code for shared
> libraries is really platform-dependent knowledge of the kind that
> libtool is supposed to hide.
>
> For example, on Mac OS X everything is position-independent by default.
>   And on some platforms you have -fpic instead of -fPIC.
>
> So I prefer the patch you had that disabled libtool if the platform is
> buggy.
>
> Paolo
Well, the detection code is too simple:

FC17 system:

    dcs-xen-52:~/tmp/libtool>uname -a
    Linux dcs-xen-52 3.8.11-100.fc17.x86_64 #1 SMP Wed May 1 19:31:26
    UTC 2013 x86_64 x86_64 x86_64 GNU/Linux
    dcs-xen-52:~/tmp/libtool>gcc -shared -fPIE -DPIE f.c -fPIC -DPIC -o f.so
    /usr/bin/ld: /tmp/ccl4By1r.o: relocation R_X86_64_PC32 against
    symbol `f' can not be used when making a shared object; recompile
    with -fPIC
    /usr/bin/ld: final link failed: Bad value
    collect2: error: ld returned 1 exit status
    dcs-xen-52:~/tmp/libtool>libtool --mode=compile gcc -g -c -fPIE
    -DPIE f.c
    libtool: compile:  gcc -g -c -DPIE f.c  -fPIC -DPIC -o .libs/f.o
    libtool: compile:  gcc -g -c -DPIE f.c -fPIE -o f.o >/dev/null 2>&1
    dcs-xen-52:~/tmp/libtool>libtool --mode=link gcc -g -o libf.la f.lo
    -rpath /usr/local/lib
    libtool: link: gcc -shared  -fPIC -DPIC  .libs/f.o -Wl,-soname
    -Wl,libf.so.0 -o .libs/libf.so.0.0.0
    libtool: link: (cd ".libs" && rm -f "libf.so.0" && ln -s
    "libf.so.0.0.0" "libf.so.0")
    libtool: link: (cd ".libs" && rm -f "libf.so" && ln -s
    "libf.so.0.0.0" "libf.so")
    libtool: link: ar cru .libs/libf.a  f.o
    libtool: link: ranlib .libs/libf.a
    libtool: link: ( cd ".libs" && rm -f "libf.la" && ln -s "../libf.la"
    "libf.la" )

CentOS 5.10:

    dcs-xen-53:~/tmp/libtool>uname -a
    Linux dcs-xen-53 2.6.18-371.el5xen #1 SMP Tue Oct 1 09:15:30 EDT
    2013 x86_64 x86_64 x86_64 GNU/Linux
    dcs-xen-53:~/tmp/libtool>gcc -shared -fPIE -DPIE f.c -fPIC -DPIC -o f.so
    /usr/bin/ld: /tmp/ccAy1vZK.o: relocation R_X86_64_PC32 against `f'
    can not be used when making a shared object; recompile with -fPIC
    /usr/bin/ld: final link failed: Bad value
    collect2: ld returned 1 exit status
    dcs-xen-53:~/tmp/libtool>libtool --mode=compile gcc -g -c -fPIE
    -DPIE f.c
    mkdir .libs
      gcc -g -c -fPIE -DPIE f.c  -fPIC -DPIC -o .libs/f.o
      gcc -g -c -fPIE -DPIE f.c -o f.o >/dev/null 2>&1
    dcs-xen-53:~/tmp/libtool>libtool --mode=link gcc -g -o libf.la f.lo
    -rpath /usr/local/lib
    gcc -shared  .libs/f.o   -Wl,-soname -Wl,libf.so.0 -o
    .libs/libf.so.0.0.0
    /usr/bin/ld: .libs/f.o: relocation R_X86_64_PC32 against `f' can not
    be used when making a shared object; recompile with -fPIC
    /usr/bin/ld: final link failed: Bad value
    collect2: ld returned 1 exit status

I have attached a patch that uses libtool to determine if gcc & libtool 
is broken.
      -Don



On 12/14/13 15:21, Don Slutz wrote:
> On 12/09/13 08:22, Paolo Bonzini wrote:
>> Il 09/12/2013 13:47, Don Slutz ha scritto:
>>> On 12/05/13 22:20, Don Slutz wrote:
>>>> On 12/05/13 16:24, Richard Henderson wrote:
>>>>> On 12/06/2013 04:18 AM, Paolo Bonzini wrote:
>>>>>> $ gcc -shared -o f.so f.c -fPIE -fPIC
>>>>>> /usr/bin/ld: /tmp/ccQc9els.o: relocation R_X86_64_PC32 against `f'
>>>>>> can not be used when making a shared object; recompile with -fPIC
>>>>>> /usr/bin/ld: final link failed: Bad value
>>>>>> collect2: ld returned 1 exit status
>>>>>>
>>>>>>
>>>>>> The bug is simply that "-fPIE -fPIC" counts as -fPIE rather than -fPIC:
>>>>>>
>>>>>> $ gcc -S -o - f.c -fPIE |grep call
>>>>>>      call    f                      # PC32 relocation
>>>>>> $ gcc -S -o - f.c -fPIC |grep call
>>>>>>      call    f@PLT                  # PLT32 relocation
>>>>> The easy workaround is to drop -fPIE when we're adding -fPIC.
>>>>>
>>>>>
>>>>> r~
>>> [snip]
>>>
>>> Attached is a much better version.  It drops -fPIE and adds -fPIC for
>>> libtool.
>> It's not much better, because using position-independent code for shared
>> libraries is really platform-dependent knowledge of the kind that
>> libtool is supposed to hide.
>>
>> For example, on Mac OS X everything is position-independent by default.
>>   And on some platforms you have -fpic instead of -fPIC.
>>
>> So I prefer the patch you had that disabled libtool if the platform is
>> buggy.
>>
>> Paolo
> Well, the detection code is too simple:
>
> FC17 system:
>
>     dcs-xen-52:~/tmp/libtool>uname -a
>     Linux dcs-xen-52 3.8.11-100.fc17.x86_64 #1 SMP Wed May 1 19:31:26
>     UTC 2013 x86_64 x86_64 x86_64 GNU/Linux
>     dcs-xen-52:~/tmp/libtool>gcc -shared -fPIE -DPIE f.c  -fPIC -DPIC
>     -o f.so
>     /usr/bin/ld: /tmp/ccl4By1r.o: relocation R_X86_64_PC32 against
>     symbol `f' can not be used when making a shared object; recompile
>     with -fPIC
>     /usr/bin/ld: final link failed: Bad value
>     collect2: error: ld returned 1 exit status
>     dcs-xen-52:~/tmp/libtool>libtool --mode=compile gcc -g -c -fPIE
>     -DPIE f.c
>     libtool: compile:  gcc -g -c -DPIE f.c  -fPIC -DPIC -o .libs/f.o
>     libtool: compile:  gcc -g -c -DPIE f.c -fPIE -o f.o >/dev/null 2>&1
>     dcs-xen-52:~/tmp/libtool>libtool --mode=link gcc -g -o libf.la
>     f.lo -rpath /usr/local/lib
>     libtool: link: gcc -shared  -fPIC -DPIC  .libs/f.o -Wl,-soname
>     -Wl,libf.so.0 -o .libs/libf.so.0.0.0
>     libtool: link: (cd ".libs" && rm -f "libf.so.0" && ln -s
>     "libf.so.0.0.0" "libf.so.0")
>     libtool: link: (cd ".libs" && rm -f "libf.so" && ln -s
>     "libf.so.0.0.0" "libf.so")
>     libtool: link: ar cru .libs/libf.a  f.o
>     libtool: link: ranlib .libs/libf.a
>     libtool: link: ( cd ".libs" && rm -f "libf.la" && ln -s
>     "../libf.la" "libf.la" )
>
> CentOS 5.10:
>
>     dcs-xen-53:~/tmp/libtool>uname -a
>     Linux dcs-xen-53 2.6.18-371.el5xen #1 SMP Tue Oct 1 09:15:30 EDT
>     2013 x86_64 x86_64 x86_64 GNU/Linux
>     dcs-xen-53:~/tmp/libtool>gcc -shared -fPIE -DPIE f.c  -fPIC -DPIC
>     -o f.so
>     /usr/bin/ld: /tmp/ccAy1vZK.o: relocation R_X86_64_PC32 against `f'
>     can not be used when making a shared object; recompile with -fPIC
>     /usr/bin/ld: final link failed: Bad value
>     collect2: ld returned 1 exit status
>     dcs-xen-53:~/tmp/libtool>libtool --mode=compile gcc -g -c -fPIE
>     -DPIE f.c
>     mkdir .libs
>      gcc -g -c -fPIE -DPIE f.c  -fPIC -DPIC -o .libs/f.o
>      gcc -g -c -fPIE -DPIE f.c -o f.o >/dev/null 2>&1
>     dcs-xen-53:~/tmp/libtool>libtool --mode=link gcc -g -o libf.la
>     f.lo -rpath /usr/local/lib
>     gcc -shared  .libs/f.o   -Wl,-soname -Wl,libf.so.0 -o
>     .libs/libf.so.0.0.0
>     /usr/bin/ld: .libs/f.o: relocation R_X86_64_PC32 against `f' can
>     not be used when making a shared object; recompile with -fPIC
>     /usr/bin/ld: final link failed: Bad value
>     collect2: ld returned 1 exit status
>
> I have attached a patch that uses libtool to determine if gcc & 
> libtool is broken.
>      -Don
>
Early today it hit me that the new check was a little to early in 
configure.  Needs to be after PIE check.
Attached is a v2 of the patch.

    -Don Slutz

 From bb68898eb787cbb1748d4aeb31a4184339d38300 Mon Sep 17 00:00:00 2001
From: Don Slutz <email address hidden>
Date: Sat, 14 Dec 2013 19:43:56 +0000
Subject: [PATCH] configure: Disable libtool if -fPIE does not work with it
  (bug #1257099)

Adjust TMPO and added TMPB, TMPL, and TMPA.  libtool needs the names
to be fixed (TMPB).

Add new functions do_libtool and libtool_prog.

Add check for broken gcc and libtool.

Signed-off-by: Don Slutz <email address hidden>
---
  configure | 63 
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++-
  1 file changed, 62 insertions(+), 1 deletion(-)

diff --git a/configure b/configure
index edfea95..852d021 100755
--- a/configure
+++ b/configure
@@ -12,7 +12,10 @@ else
  fi

  TMPC="${TMPDIR1}/qemu-conf-${RANDOM}-$$-${RANDOM}.c"
-TMPO="${TMPDIR1}/qemu-conf-${RANDOM}-$$-${RANDOM}.o"
+TMPB="qemu-conf-${RANDOM}-$$-${RANDOM}"
+TMPO="${TMPDIR1}/${TMPB}.o"
+TMPL="${TMPDIR1}/${TMPB}.lo"
+TMPA="${TMPDIR1}/lib${TMPB}.la"
  TMPE="${TMPDIR1}/qemu-conf-${RANDOM}-$$-${RANDOM}.exe"

  # NB: do not call "exit" in the trap handler; this is buggy with some 
shells;
@@ -86,6 +89,38 @@ compile_prog() {
    do_cc $QEMU_CFLAGS $local_cflags -o $TMPE $TMPC $LDFLAGS $local_ldflags
  }

+do_libtool() {
+    local mode=$1
+    shift
+    # Run the compiler, capturing its output to the log.
+    echo $libtool $mode --tag=CC $cc "$@" >> config.log
+    $libtool $mode --tag=CC $cc "$@" >> config.log 2>&1 || return $?
+    # Test passed. If this is an --enable-werror build, rerun
+    # the test with -Werror and bail out if it fails. This
+    # makes warning-generating-errors in configure test code
+    # obvious to developers.
+    if test "$werror" != "yes"; then
+        return 0
+    fi
+    # Don't bother rerunning the compile if we were already using -Werror
+    case "$*" in
+        *-Werror*)
+           return 0
+        ;;
+    esac
+    echo $libtool $mode --tag=CC $cc -Werror "$@" >> config.log
+    $libtool $mode --tag=CC $cc -Werror "$@" >> config.log 2>&1 && 
return $?
+    error_exit "configure test passed without -Werror but failed with 
-Werror." \
+        "This is probably a bug in the configure script. The failing 
command" \
+        "will be at the bottom of config.log." \
+        "You can run configure with --disable-werror to bypass this check."
+}
+
+libtool_prog() {
+    do_libtool --mode=compile $QEMU_CFLAGS -c -fPIE -DPIE -o $TMPO 
$TMPC || return $?
+    do_libtool --mode=link $LDFLAGS -o $TMPA $TMPL -rpath /usr/local/lib
+}
+
  # symbolically link $1 to $2.  Portable version of "ln -sf".
  symlink() {
    rm -rf "$2"
@@ -1367,6 +1402,32 @@ EOF
    fi
  fi

+# check for broken gcc and libtool in RHEL5
+if test -n "$libtool" -a "$pie" != "no" ; then
+  cat > $TMPC <<EOF
+
+void *f(unsigned char *buf, int len);
+void *g(unsigned char *buf, int len);
+
+void *
+f(unsigned char *buf, int len)
+{
+    return (void*)0L;
+}
+
+void *
+g(unsigned char *buf, int len)
+{
+    return f(buf, len);
+}
+
+EOF
+  if ! libtool_prog; then
+    echo "Disabling libtool due to broken toolchain support"
+    libtool=
+  fi
+fi
+
  ##########################################
  # __sync_fetch_and_and requires at least -march=i486. Many toolchains
  # use i686 as default anyway, but for those that don't, an explicit
-- 
1.8.2.1




Adjust TMPO and added TMPB, TMPL, and TMPA.  libtool needs the names
to be fixed (TMPB).

Add new functions do_libtool and libtool_prog.

Add check for broken gcc and libtool.

Signed-off-by: Don Slutz <email address hidden>
---
Was posted as an attachment.

https://lists.gnu.org/archive/html/qemu-devel/2013-12/msg02678.html

 configure | 63 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 62 insertions(+), 1 deletion(-)

diff --git a/configure b/configure
index edfea95..852d021 100755
--- a/configure
+++ b/configure
@@ -12,7 +12,10 @@ else
 fi
 
 TMPC="${TMPDIR1}/qemu-conf-${RANDOM}-$$-${RANDOM}.c"
-TMPO="${TMPDIR1}/qemu-conf-${RANDOM}-$$-${RANDOM}.o"
+TMPB="qemu-conf-${RANDOM}-$$-${RANDOM}"
+TMPO="${TMPDIR1}/${TMPB}.o"
+TMPL="${TMPDIR1}/${TMPB}.lo"
+TMPA="${TMPDIR1}/lib${TMPB}.la"
 TMPE="${TMPDIR1}/qemu-conf-${RANDOM}-$$-${RANDOM}.exe"
 
 # NB: do not call "exit" in the trap handler; this is buggy with some shells;
@@ -86,6 +89,38 @@ compile_prog() {
   do_cc $QEMU_CFLAGS $local_cflags -o $TMPE $TMPC $LDFLAGS $local_ldflags
 }
 
+do_libtool() {
+    local mode=$1
+    shift
+    # Run the compiler, capturing its output to the log.
+    echo $libtool $mode --tag=CC $cc "$@" >> config.log
+    $libtool $mode --tag=CC $cc "$@" >> config.log 2>&1 || return $?
+    # Test passed. If this is an --enable-werror build, rerun
+    # the test with -Werror and bail out if it fails. This
+    # makes warning-generating-errors in configure test code
+    # obvious to developers.
+    if test "$werror" != "yes"; then
+        return 0
+    fi
+    # Don't bother rerunning the compile if we were already using -Werror
+    case "$*" in
+        *-Werror*)
+           return 0
+        ;;
+    esac
+    echo $libtool $mode --tag=CC $cc -Werror "$@" >> config.log
+    $libtool $mode --tag=CC $cc -Werror "$@" >> config.log 2>&1 && return $?
+    error_exit "configure test passed without -Werror but failed with -Werror." \
+        "This is probably a bug in the configure script. The failing command" \
+        "will be at the bottom of config.log." \
+        "You can run configure with --disable-werror to bypass this check."
+}
+
+libtool_prog() {
+    do_libtool --mode=compile $QEMU_CFLAGS -c -fPIE -DPIE -o $TMPO $TMPC || return $?
+    do_libtool --mode=link $LDFLAGS -o $TMPA $TMPL -rpath /usr/local/lib
+}
+
 # symbolically link $1 to $2.  Portable version of "ln -sf".
 symlink() {
   rm -rf "$2"
@@ -1367,6 +1402,32 @@ EOF
   fi
 fi
 
+# check for broken gcc and libtool in RHEL5
+if test -n "$libtool" -a "$pie" != "no" ; then
+  cat > $TMPC <<EOF
+
+void *f(unsigned char *buf, int len);
+void *g(unsigned char *buf, int len);
+
+void *
+f(unsigned char *buf, int len)
+{
+    return (void*)0L;
+}
+
+void *
+g(unsigned char *buf, int len)
+{
+    return f(buf, len);
+}
+
+EOF
+  if ! libtool_prog; then
+    echo "Disabling libtool due to broken toolchain support"
+    libtool=
+  fi
+fi
+
 ##########################################
 # __sync_fetch_and_and requires at least -march=i486. Many toolchains
 # use i686 as default anyway, but for those that don't, an explicit
-- 
1.8.2.1



On 01/02/14 21:12, Don Slutz wrote:

Ping.

> Adjust TMPO and added TMPB, TMPL, and TMPA.  libtool needs the names
> to be fixed (TMPB).
>
> Add new functions do_libtool and libtool_prog.
>
> Add check for broken gcc and libtool.
>
> Signed-off-by: Don Slutz <email address hidden>
> ---
> Was posted as an attachment.
>
> https://lists.gnu.org/archive/html/qemu-devel/2013-12/msg02678.html
>
>   configure | 63 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++-
>   1 file changed, 62 insertions(+), 1 deletion(-)
>
> diff --git a/configure b/configure
> index edfea95..852d021 100755
> --- a/configure
> +++ b/configure
> @@ -12,7 +12,10 @@ else
>   fi
>   
>   TMPC="${TMPDIR1}/qemu-conf-${RANDOM}-$$-${RANDOM}.c"
> -TMPO="${TMPDIR1}/qemu-conf-${RANDOM}-$$-${RANDOM}.o"
> +TMPB="qemu-conf-${RANDOM}-$$-${RANDOM}"
> +TMPO="${TMPDIR1}/${TMPB}.o"
> +TMPL="${TMPDIR1}/${TMPB}.lo"
> +TMPA="${TMPDIR1}/lib${TMPB}.la"
>   TMPE="${TMPDIR1}/qemu-conf-${RANDOM}-$$-${RANDOM}.exe"
>   
>   # NB: do not call "exit" in the trap handler; this is buggy with some shells;
> @@ -86,6 +89,38 @@ compile_prog() {
>     do_cc $QEMU_CFLAGS $local_cflags -o $TMPE $TMPC $LDFLAGS $local_ldflags
>   }
>   
> +do_libtool() {
> +    local mode=$1
> +    shift
> +    # Run the compiler, capturing its output to the log.
> +    echo $libtool $mode --tag=CC $cc "$@" >> config.log
> +    $libtool $mode --tag=CC $cc "$@" >> config.log 2>&1 || return $?
> +    # Test passed. If this is an --enable-werror build, rerun
> +    # the test with -Werror and bail out if it fails. This
> +    # makes warning-generating-errors in configure test code
> +    # obvious to developers.
> +    if test "$werror" != "yes"; then
> +        return 0
> +    fi
> +    # Don't bother rerunning the compile if we were already using -Werror
> +    case "$*" in
> +        *-Werror*)
> +           return 0
> +        ;;
> +    esac
> +    echo $libtool $mode --tag=CC $cc -Werror "$@" >> config.log
> +    $libtool $mode --tag=CC $cc -Werror "$@" >> config.log 2>&1 && return $?
> +    error_exit "configure test passed without -Werror but failed with -Werror." \
> +        "This is probably a bug in the configure script. The failing command" \
> +        "will be at the bottom of config.log." \
> +        "You can run configure with --disable-werror to bypass this check."
> +}
> +
> +libtool_prog() {
> +    do_libtool --mode=compile $QEMU_CFLAGS -c -fPIE -DPIE -o $TMPO $TMPC || return $?
> +    do_libtool --mode=link $LDFLAGS -o $TMPA $TMPL -rpath /usr/local/lib
> +}
> +
>   # symbolically link $1 to $2.  Portable version of "ln -sf".
>   symlink() {
>     rm -rf "$2"
> @@ -1367,6 +1402,32 @@ EOF
>     fi
>   fi
>   
> +# check for broken gcc and libtool in RHEL5
> +if test -n "$libtool" -a "$pie" != "no" ; then
> +  cat > $TMPC <<EOF
> +
> +void *f(unsigned char *buf, int len);
> +void *g(unsigned char *buf, int len);
> +
> +void *
> +f(unsigned char *buf, int len)
> +{
> +    return (void*)0L;
> +}
> +
> +void *
> +g(unsigned char *buf, int len)
> +{
> +    return f(buf, len);
> +}
> +
> +EOF
> +  if ! libtool_prog; then
> +    echo "Disabling libtool due to broken toolchain support"
> +    libtool=
> +  fi
> +fi
> +
>   ##########################################
>   # __sync_fetch_and_and requires at least -march=i486. Many toolchains
>   # use i686 as default anyway, but for those that don't, an explicit



Patch has been included here:
http://git.qemu.org/?p=qemu.git;a=commitdiff;h=66518bf668f09eaab14c174
==> Fix released.