Installing wine on a laptop of my friend that have the same configuration about USE (global & local) I obtain the error:

______________________________________
[ebuild N ] app-emulation/wine-1.7.41 USE="X alsa cups custom-cflags fontconfig gecko gphoto2 gsm gstreamer jpeg lcms ldap mono mp3 ncurses nls opencl opengl perl png prelink pulseaudio realtime run-exes scanner ssl threads truetype udisks v4l xcomposite xinerama xml -capi -dos -netapi -odbc -openal -osmesa -oss -pcap -pipelight -s3tc -samba (-selinux) -staging {-test} -vaapi" ABI_X86="32 (64) (-x32)" LINGUAS="it -ar -bg -ca -cs -da -de -el -en -en_US -eo -es -fa -fi -fr -he -hi -hr -hu -ja -ko -lt -ml -nb_NO -nl -or -pa -pl -pt_BR -pt_PT -rm -ro -ru -sk -sl -sr_RS@cyrillic -sr_RS@latin -sv -te -th -tr -uk -wa -zh_CN -zh_TW"
[blocks B ] x11-libs/libXdmcp[abi_x86_32(-)] ("x11-libs/libXdmcp[abi_x86_32(-)]" is blocking app-emulation/emul-linux-x86-xlibs-20140508)
[blocks B ] x11-libs/libxcb[abi_x86_32(-)] ("x11-libs/libxcb[abi_x86_32(-)]" is blocking app-emulation/emul-linux-x86-xlibs-20140508)
[blocks B ] x11-libs/libXvMC[abi_x86_32(-)] ("x11-libs/libXvMC[abi_x86_32(-)]" is blocking app-emulation/emul-linux-x86-xlibs-20140508)
[blocks B ] app-emulation/emul-linux-x86-baselibs[-abi_x86_32(-)] ("app-emulation/emul-linux-x86-baselibs[-abi_x86_32(-)]" is blocking app-arch/bzip2-1.0.6-r6, sys-libs/ncurses-5.9-r3, sys-libs/zlib-1.2.8-r1, sys-libs/gpm-1.20.7-r2, dev-libs/elfutils-0.158, sys-apps/attr-2.4.47-r3)
[blocks B ] x11-libs/libXfixes[abi_x86_32(-)] ("x11-libs/libXfixes[abi_x86_32(-)]" is blocking app-emulation/emul-linux-x86-xlibs-20140508)
[blocks B ] x11-libs/libXdamage[abi_x86_32(-)] ("x11-libs/libXdamage[abi_x86_32(-)]" is blocking app-emulation/emul-linux-x86-xlibs-20140508)
[blocks B ] x11-libs/libX11[abi_x86_32(-)] ("x11-libs/libX11[abi_x86_32(-)]" is blocking app-emulation/emul-linux-x86-xlibs-20140508)
[blocks B ] x11-libs/libXxf86vm[abi_x86_32(-)] ("x11-libs/libXxf86vm[abi_x86_32(-)]" is blocking app-emulation/emul-linux-x86-xlibs-20140508)
[blocks B ] x11-libs/libXext[abi_x86_32(-)] ("x11-libs/libXext[abi_x86_32(-)]" is blocking app-emulation/emul-linux-x86-xlibs-20140508)
[blocks B ] app-emulation/emul-linux-x86-baselibs[-abi_x86_32(-)] ("app-emulation/emul-linux-x86-baselibs[-abi_x86_32(-)]" is blocking dev-libs/expat-2.1.0-r4, dev-libs/libffi-3.0.13-r1, sys-devel/llvm-3.5.0, dev-libs/glib-2.42.2, sys-fs/eudev-1.5.3-r2)
[blocks B ] media-libs/mesa[abi_x86_32(-)] ("media-libs/mesa[abi_x86_32(-)]" is blocking app-emulation/emul-linux-x86-opengl-20140508-r1)
[blocks B ] x11-libs/libpciaccess[abi_x86_32(-)] ("x11-libs/libpciaccess[abi_x86_32(-)]" is blocking app-emulation/emul-linux-x86-xlibs-20140508)
[blocks B ] x11-libs/libXv[abi_x86_32(-)] ("x11-libs/libXv[abi_x86_32(-)]" is blocking app-emulation/emul-linux-x86-xlibs-20140508)
[blocks B ] x11-libs/libvdpau[abi_x86_32(-)] ("x11-libs/libvdpau[abi_x86_32(-)]" is blocking app-emulation/emul-linux-x86-xlibs-20140508)
[blocks B ] >=app-arch/xz-utils-5.0.5-r1[abi_x86_32(-)] (">=app-arch/xz-utils-5.0.5-r1[abi_x86_32(-)]" is blocking app-emulation/emul-linux-x86-baselibs-20140508-r12)
[blocks B ] app-emulation/emul-linux-x86-xlibs[-abi_x86_32(-)] ("app-emulation/emul-linux-x86-xlibs[-abi_x86_32(-)]" is blocking x11-proto/kbproto-1.0.6-r1, x11-proto/fixesproto-5.0-r1, dev-libs/libpthread-stubs-0.3-r1, x11-proto/xf86bigfontproto-1.2.0-r1, x11-libs/libXdamage-1.1.4-r1, x11-proto/inputproto-2.3.1, x11-libs/libXext-1.3.3, x11-proto/glproto-1.4.17-r1, x11-libs/libXv-1.0.10, x11-proto/xextproto-7.3.0, x11-libs/libX11-1.6.2, x11-proto/presentproto-1.0, x11-libs/libXxf86vm-1.1.4, x11-libs/libvdpau-0.9, x11-proto/xproto-7.0.27, x11-libs/libXfixes-5.0.1, x11-libs/libpciaccess-0.13.3, x11-libs/libxcb-1.11-r1, x11-libs/libxshmfence-1.2, x11-proto/dri2proto-2.8-r1, x11-proto/damageproto-1.2.1-r1, x11-proto/dri3proto-1.0, x11-libs/libdrm-2.4.61, x11-proto/xf86driproto-2.1.1-r1, x11-libs/libXdmcp-1.1.1-r1, x11-proto/videoproto-2.3.2, x11-proto/xf86vidmodeproto-2.3.1-r1, x11-libs/libXau-1.0.8, x11-libs/libXvMC-1.0.8)
[blocks B ] x11-libs/libXau[abi_x86_32(-)] ("x11-libs/libXau[abi_x86_32(-)]" is blocking app-emulation/emul-linux-x86-xlibs-20140508)
[blocks B ] app-emulation/emul-linux-x86-opengl[-abi_x86_32(-)] ("app-emulation/emul-linux-x86-opengl[-abi_x86_32(-)]" is blocking x11-libs/libdrm-2.4.61, media-libs/mesa-10.5.2)

• Error: The above package list contains packages which cannot be
• installed at the same time on the same system.

(app-arch/xz-utils-5.0.8::gentoo, installed) pulled in by
app-arch/xz-utils required by (sys-auth/rtkit-0.11-r1::gentoo, ebuild scheduled for merge)

(x11-proto/inputproto-2.3.1::gentoo, installed) pulled in by
x11-proto/inputproto required by (app-emulation/wine-1.7.41::gentoo, ebuild scheduled for merge)

(x11-proto/xextproto-7.3.0::gentoo, installed) pulled in by
x11-proto/xextproto required by (app-emulation/wine-1.7.41::gentoo, ebuild scheduled for merge)

(sys-libs/gpm-1.20.7-r2::gentoo, installed) pulled in by
sys-libs/gpm required by @selected

(dev-libs/elfutils-0.158::gentoo, installed) pulled in by
>=dev-libs/elfutils-0.100[static-libs(+)] required by (sys-devel/prelink-20130503::gentoo, ebuild scheduled for merge)

(x11-libs/libXext-1.3.3::gentoo, installed) pulled in by
x11-libs/libXext required by (app-emulation/wine-1.7.41::gentoo, ebuild scheduled for merge)

(x11-proto/xf86vidmodeproto-2.3.1-r1::gentoo, installed) pulled in by
x11-proto/xf86vidmodeproto required by (app-emulation/wine-1.7.41::gentoo, ebuild scheduled for merge)

(x11-libs/libXxf86vm-1.1.4::gentoo, installed) pulled in by
x11-libs/libXxf86vm required by (app-emulation/wine-1.7.41::gentoo, ebuild scheduled for merge)

(app-emulation/emul-linux-x86-xlibs-20140508::gentoo, ebuild scheduled for merge) pulled in by
>=app-emulation/emul-linux-x86-xlibs-2.1[development,-abi_x86_32(-)] required by (app-emulation/wine-1.7.41::gentoo, ebuild scheduled for merge)
app-emulation/emul-linux-x86-xlibs[development,-abi_x86_32(-)] required by (app-emulation/wine-1.7.41::gentoo, ebuild scheduled for merge)
~app-emulation/emul-linux-x86-xlibs-20140508 required by (app-emulation/emul-linux-x86-medialibs-20140508-r6::gentoo, ebuild scheduled for merge)
>=app-emulation/emul-linux-x86-xlibs-20100611 required by (app-emulation/emul-linux-x86-opengl-20140508-r1::gentoo, ebuild scheduled for merge)

(app-emulation/emul-linux-x86-baselibs-20140508-r12::gentoo, ebuild scheduled for merge) pulled in by
>=app-emulation/emul-linux-x86-baselibs-20131008[development,-abi_x86_32(-)] required by (app-emulation/wine-1.7.41::gentoo, ebuild scheduled for merge)
~app-emulation/emul-linux-x86-baselibs-20140508[abi_x86_32=] (~app-emulation/emul-linux-x86-baselibs-20140508[-abi_x86_32]) required by (app-emulation/emul-linux-x86-soundlibs-20140508::gentoo, ebuild scheduled for merge)
app-emulation/emul-linux-x86-baselibs[development,-abi_x86_32(-)] required by (app-emulation/wine-1.7.41::gentoo, ebuild scheduled for merge)
app-emulation/emul-linux-x86-baselibs required by (app-emulation/wine-1.7.41::gentoo, ebuild scheduled for merge)
>=app-emulation/emul-linux-x86-baselibs-20130224[development,-abi_x86_32(-)] required by (app-emulation/wine-1.7.41::gentoo, ebuild scheduled for merge)
~app-emulation/emul-linux-x86-baselibs-20140508 required by (app-emulation/emul-linux-x86-medialibs-20140508-r6::gentoo, ebuild scheduled for merge)
~app-emulation/emul-linux-x86-baselibs-20140508 required by (app-emulation/emul-linux-x86-db-20140508-r1::gentoo, ebuild scheduled for merge)
~app-emulation/emul-linux-x86-baselibs-20140508 required by (app-emulation/emul-linux-x86-xlibs-20140508::gentoo, ebuild scheduled for merge)

(sys-libs/ncurses-5.9-r3::gentoo, installed) pulled in by
>=sys-libs/ncurses-5.2:= required by (app-emulation/wine-1.7.41::gentoo, ebuild scheduled for merge)

(media-libs/mesa-10.5.2::gentoo, installed) pulled in by
>=media-libs/mesa-9.1.6[opencl,abi_x86_32(-)?,abi_x86_64(-)?,abi_x86_x32(-)?,abi_mips_n32(-)?,abi_mips_n64(-)?,abi_mips_o32(-)?,abi_ppc_32(-)?,abi_ppc_64(-)?,abi_s390_32(-)?,abi_s390_64(-)?] (>=media-libs/mesa-9.1.6[opencl,abi_x86_32(-),abi_x86_64(-)]) required by (virtual/opencl-0-r4::gentoo, installed)
>=media-libs/mesa-9.1.6[abi_x86_32(-)?,abi_x86_64(-)?,abi_x86_x32(-)?,abi_mips_n32(-)?,abi_mips_n64(-)?,abi_mips_o32(-)?,abi_ppc_32(-)?,abi_ppc_64(-)?,abi_s390_32(-)?,abi_s390_64(-)?] (>=media-libs/mesa-9.1.6[abi_x86_32(-),abi_x86_64(-)]) required by (virtual/opengl-7.0-r1::gentoo, installed)
media-libs/mesa required by (app-emulation/emul-linux-x86-opengl-20140508-r1::gentoo, ebuild scheduled for merge)

(app-emulation/emul-linux-x86-opengl-20140508-r1::gentoo, ebuild scheduled for merge) pulled in by
app-emulation/emul-linux-x86-opengl[development,-abi_x86_32(-)] required by (app-emulation/wine-1.7.41::gentoo, ebuild scheduled for merge)
app-emulation/emul-linux-x86-opengl required by (app-emulation/emul-linux-x86-xlibs-20140508::gentoo, ebuild scheduled for merge)

For more information about Blocked Packages, please refer to the following
section of the Gentoo Linux x86 Handbook (architecture is irrelevant):

http://www.gentoo.org/doc/en/handbook/handbook-x86.xml?full=1#blocked

Vaio-i5 ~ #
___________________________

Thanks for suggestions