root@starbox /home/nico %  CFLAGS="-march=prescott -O2 -pipe" CXXFLAGS="-march=prescott -O2 -pipe" LDFLAGS="" emerge -1v xvid

These are the packages that would be merged, in order:

Calculating dependencies... done!
[ebuild   R   ] media-libs/xvid-1.1.2  USE="(-altivec) -doc" 0 kB 

Total: 1 package (1 reinstall), Size of downloads: 0 kB


>>> Emerging (1 of 1) media-libs/xvid-1.1.2 to /
 * xvidcore-1.1.2.tar.bz2 RMD160 ;-) ...                                                                                                                                      [ ok ]
 * xvidcore-1.1.2.tar.bz2 SHA1 ;-) ...                                                                                                                                        [ ok ]
 * xvidcore-1.1.2.tar.bz2 SHA256 ;-) ...                                                                                                                                      [ ok ]
 * xvidcore-1.1.2.tar.bz2 size ;-) ...                                                                                                                                        [ ok ]
 * xvid-1.1.2-noexec-stack.patch.bz2 RMD160 ;-) ...                                                                                                                           [ ok ]
 * xvid-1.1.2-noexec-stack.patch.bz2 SHA1 ;-) ...                                                                                                                             [ ok ]
 * xvid-1.1.2-noexec-stack.patch.bz2 SHA256 ;-) ...                                                                                                                           [ ok ]
 * xvid-1.1.2-noexec-stack.patch.bz2 size ;-) ...                                                                                                                             [ ok ]
 * checking ebuild checksums ;-) ...                                                                                                                                          [ ok ]
 * checking auxfile checksums ;-) ...                                                                                                                                         [ ok ]
 * checking miscfile checksums ;-) ...                                                                                                                                        [ ok ]
 * checking xvidcore-1.1.2.tar.bz2 ;-) ...                                                                                                                                    [ ok ]
 * checking xvid-1.1.2-noexec-stack.patch.bz2 ;-) ...                                                                                                                         [ ok ]
>>> Unpacking source...
>>> Unpacking xvidcore-1.1.2.tar.bz2 to /portage/tmp/portage/media-libs/xvid-1.1.2/work
>>> Unpacking xvid-1.1.2-noexec-stack.patch.bz2 to /portage/tmp/portage/media-libs/xvid-1.1.2/work
 * Applying xvid-1.1.0_beta2-altivec.patch ...                                                                                                                                [ ok ]
 * Applying xvid-1.1.2-noexec-stack.patch ...                                                                                                                                 [ ok ]
 * Applying xvid-1.1.0-3dnow-2.patch ...                                                                                                                                      [ ok ]
 * Running eautoreconf in '/portage/tmp/portage/media-libs/xvid-1.1.2/work/xvidcore-1.1.2/build/generic' ...
 * Running aclocal ...                                                                                                                                                        [ ok ]
 * Running autoconf ...                                                                                                                                                       [ ok ]
>>> Source unpacked.
>>> Compiling source in /portage/tmp/portage/media-libs/xvid-1.1.2/work/xvidcore-1.1.2/build/generic ...
 * econf: updating xvidcore-1.1.2/build/generic/config.guess with /usr/share/gnuconfig/config.guess
 * econf: updating xvidcore-1.1.2/build/generic/config.sub with /usr/share/gnuconfig/config.sub
./configure --prefix=/usr --host=i686-pc-linux-gnu --mandir=/usr/share/man --infodir=/usr/share/info --datadir=/usr/share --sysconfdir=/etc --localstatedir=/var/lib --disable-altivec --build=i686-pc-linux-gnu
checking build system type... i686-pc-linux-gnu
checking host system type... i686-pc-linux-gnu
checking target system type... i686-pc-linux-gnu
checking whether to use default CFLAGS... no
checking for i686-pc-linux-gnu-gcc... i686-pc-linux-gnu-gcc
checking for C compiler default output file name... a.out
checking whether the C compiler works... yes
checking whether we are cross compiling... no
checking for suffix of executables... 
checking for suffix of object files... o
checking whether we are using the GNU C compiler... yes
checking whether i686-pc-linux-gnu-gcc accepts -g... yes
checking for i686-pc-linux-gnu-gcc option to accept ISO C89... none needed
checking for a BSD-compatible install... /usr/bin/install -c
checking for i686-pc-linux-gnu-ranlib... i686-pc-linux-gnu-ranlib
checking for whether to use assembly code... yes
checking for architecture type... ia32
checking how to run the C preprocessor... i686-pc-linux-gnu-gcc -E
checking for grep that handles long lines and -e... /bin/grep
checking for egrep... /bin/grep -E
checking for ANSI C header files... yes
checking for sys/types.h... yes
checking for sys/stat.h... yes
checking for stdlib.h... yes
checking for string.h... yes
checking for memory.h... yes
checking for strings.h... yes
checking for inttypes.h... yes
checking for stdint.h... yes
checking for unistd.h... yes
checking for int *... yes
checking size of int *... 4
checking whether byte ordering is bigendian... no
checking for build extensions... .so .a .o
checking for platform specific LDFLAGS/CFLAGS... ok
checking for yasm... yes
checking for asm object format... elf
checking if altivec support has to be activated... no
checking stdio.h usability... yes
checking stdio.h presence... yes
checking for stdio.h... yes
checking signal.h usability... yes
checking signal.h presence... yes
checking for signal.h... yes
checking for stdlib.h... (cached) yes
checking for string.h... (cached) yes
checking assert.h usability... yes
checking assert.h presence... yes
checking for assert.h... yes
checking math.h usability... yes
checking math.h presence... yes
checking for math.h... yes
configure: creating ./config.status
config.status: creating platform.inc
  C: ./decoder.c
  C: ./encoder.c
  D: =build
  C: ./xvid.c
  C: bitstream/bitstream.c
  C: bitstream/cbp.c
  C: bitstream/mbcoding.c
  C: dct/fdct.c
  C: dct/idct.c
  C: dct/simple_idct.c
  C: image/colorspace.c
  C: image/image.c
  C: image/interpolate8x8.c
  C: image/font.c
  C: image/postprocessing.c
  C: image/qpel.c
  C: image/reduced.c
  C: motion/estimation_bvop.c
  C: motion/estimation_common.c
  C: motion/estimation_gmc.c
  C: motion/estimation_pvop.c
  C: motion/estimation_rd_based.c
  C: motion/estimation_rd_based_bvop.c
  C: motion/gmc.c
  C: motion/motion_comp.c
  C: motion/vop_type_decision.c
  C: motion/sad.c
  C: prediction/mbprediction.c
  C: plugins/plugin_single.c
  C: plugins/plugin_2pass1.c
  C: plugins/plugin_2pass2.c
  C: plugins/plugin_lumimasking.c
  C: plugins/plugin_dump.c
  C: plugins/plugin_psnr.c
  C: quant/quant_h263.c
  C: quant/quant_matrix.c
  C: quant/quant_mpeg.c
  C: utils/emms.c
  C: utils/mbtransquant.c
  C: utils/mem_align.c
  C: utils/mem_transfer.c
  C: utils/timer.c
  A: bitstream/x86_asm/cbp_3dne.asm
  A: bitstream/x86_asm/cbp_mmx.asm
*** glibc detected *** yasm: free(): invalid pointer: 0x4014e130 ***
======= Backtrace: =========
/lib/libc.so.6[0x40091277]
/lib/libc.so.6(__libc_free+0x7a)[0x4009281f]
yasm[0x806926c]
======= Memory map: ========
08048000-080a5000 r-xp 00000000 08:03 2849222    /usr/bin/yasm
080a5000-080a7000 rw-p 0005c000 08:03 2849222    /usr/bin/yasm
080a7000-0816a000 rw-p 080a7000 00:00 0          [heap]
40000000-4001a000 r-xp 00000000 08:03 82206      /lib/ld-2.5.so
4001a000-4001b000 r--p 00019000 08:03 82206      /lib/ld-2.5.so
4001b000-4001c000 rw-p 0001a000 08:03 82206      /lib/ld-2.5.so
4001c000-4001d000 rw-p 4001c000 00:00 0 
4001d000-40022000 r-xp 00000000 08:03 2846791    /usr/lib/libsandbox.so.0.0.0
40022000-40023000 rw-p 00005000 08:03 2846791    /usr/lib/libsandbox.so.0.0.0
40023000-40025000 rw-p 40023000 00:00 0 
4002f000-4014b000 r-xp 00000000 08:03 82210      /lib/libc-2.5.so
4014b000-4014c000 r--p 0011b000 08:03 82210      /lib/libc-2.5.so
4014c000-4014e000 rw-p 0011c000 08:03 82210      /lib/libc-2.5.so
4014e000-40151000 rw-p 4014e000 00:00 0 
40151000-40153000 r-xp 00000000 08:03 82213      /lib/libdl-2.5.so
40153000-40154000 r--p 00001000 08:03 82213      /lib/libdl-2.5.so
40154000-40155000 rw-p 00002000 08:03 82213      /lib/libdl-2.5.so
40155000-40156000 rw-p 40155000 00:00 0 
40156000-4015f000 r-xp 00000000 08:03 3352198    /usr/lib/gcc/i686-pc-linux-gnu/4.1.2/libgcc_s.so.1
4015f000-40160000 rw-p 00008000 08:03 3352198    /usr/lib/gcc/i686-pc-linux-gnu/4.1.2/libgcc_s.so.1
40200000-40221000 rw-p 40200000 00:00 0 
40221000-40300000 ---p 40221000 00:00 0 
bf835000-bf84d000 rw-p bf835000 00:00 0          [stack]
ffffe000-fffff000 r-xp 00000000 00:00 0          [vdso]
make: *** [bitstream/x86_asm/cbp_3dne.o] Aborted
make: *** Waiting for unfinished jobs....
*** glibc detected *** yasm: free(): invalid pointer: 0x4014e130 ***
======= Backtrace: =========
/lib/libc.so.6[0x40091277]
/lib/libc.so.6(__libc_free+0x7a)[0x4009281f]
yasm[0x806926c]
======= Memory map: ========
08048000-080a5000 r-xp 00000000 08:03 2849222    /usr/bin/yasm
080a5000-080a7000 rw-p 0005c000 08:03 2849222    /usr/bin/yasm
080a7000-08166000 rw-p 080a7000 00:00 0          [heap]
40000000-4001a000 r-xp 00000000 08:03 82206      /lib/ld-2.5.so
4001a000-4001b000 r--p 00019000 08:03 82206      /lib/ld-2.5.so
4001b000-4001c000 rw-p 0001a000 08:03 82206      /lib/ld-2.5.so
4001c000-4001d000 rw-p 4001c000 00:00 0 
4001d000-40022000 r-xp 00000000 08:03 2846791    /usr/lib/libsandbox.so.0.0.0
40022000-40023000 rw-p 00005000 08:03 2846791    /usr/lib/libsandbox.so.0.0.0
40023000-40025000 rw-p 40023000 00:00 0 
4002f000-4014b000 r-xp 00000000 08:03 82210      /lib/libc-2.5.so
4014b000-4014c000 r--p 0011b000 08:03 82210      /lib/libc-2.5.so
4014c000-4014e000 rw-p 0011c000 08:03 82210      /lib/libc-2.5.so
4014e000-40151000 rw-p 4014e000 00:00 0 
40151000-40153000 r-xp 00000000 08:03 82213      /lib/libdl-2.5.so
40153000-40154000 r--p 00001000 08:03 82213      /lib/libdl-2.5.so
40154000-40155000 rw-p 00002000 08:03 82213      /lib/libdl-2.5.so
40155000-40156000 rw-p 40155000 00:00 0 
40156000-4015f000 r-xp 00000000 08:03 3352198    /usr/lib/gcc/i686-pc-linux-gnu/4.1.2/libgcc_s.so.1
4015f000-40160000 rw-p 00008000 08:03 3352198    /usr/lib/gcc/i686-pc-linux-gnu/4.1.2/libgcc_s.so.1
40200000-40221000 rw-p 40200000 00:00 0 
40221000-40300000 ---p 40221000 00:00 0 
bfd96000-bfdae000 rw-p bfd96000 00:00 0          [stack]
ffffe000-fffff000 r-xp 00000000 00:00 0          [vdso]
make: *** [bitstream/x86_asm/cbp_mmx.o] Aborted

!!! ERROR: media-libs/xvid-1.1.2 failed.
Call stack:
  ebuild.sh, line 1614:   Called dyn_compile
  ebuild.sh, line 971:   Called qa_call 'src_compile'
  environment, line 3465:   Called src_compile
  xvid-1.1.2.ebuild, line 42:   Called die

!!! emake failed
!!! If you need support, post the topmost build error, and the call stack if relevant.
!!! A complete build log is located at '/portage/log/media-libs:xvid-1.1.2:20070227-221815.log'.