dwarf: Get correct return from expression evaluation
dwarf: Get correct return from expression evaluation

Currently the expression evaluation always succeeds,
and possible error is not propagated to the caller.

The ',' operator makes the condition always return 0.

Signed-off-by: Jiri Olsa <2c6594f608aa3d41e98d48846a6328831f7084ad@redhat.com>
Tested-by: Paul Pluzhnikov <eceb66078c8d0c18f1ed9d9459677288f3b6e0b8@google.com>

cloudius-systems/libunwind,rogwfu/libunwind,geekboxzone/mmallow_external_libunwind,tony/libunwind,djwatson/libunwind,joyent/libunwind,tronical/libunwind,rogwfu/libunwind,androidarmv6/android_external_libunwind,geekboxzone/lollipop_external_libunwind,DroidSim/platform_external_libunwind,libunwind/libunwind,vegard/libunwind,frida/libunwind,cms-externals/libunwind,project-zerus/libunwind,evaautomation/libunwind,yuyichao/libunwind,rantala/libunwind,dagar/libunwind,martyone/libunwind,rantala/libunwind,tkelman/libunwind,atanasyan/libunwind,evaautomation/libunwind,pathscale/libunwind,bo-on-software/libunwind,SyndicateRogue/libunwind,CyanogenMod/android_external_libunwind,dagar/libunwind,martyone/libunwind,evaautomation/libunwind,rantala/libunwind,SyndicateRogue/libunwind,atanasyan/libunwind,zeldin/platform_external_libunwind,vtjnash/libunwind,tony/libunwind,tronical/libunwind,Chilledheart/libunwind,vegard/libunwind,martyone/libunwind,mpercy/libunwind,rntz/libunwind,Keno/libunwind,dropbox/libunwind,fdoray/libunwind,DroidSim/platform_external_libunwind,krytarowski/libunwind,wdv4758h/libunwind,maltek/platform_external_libunwind,unkadoug/libunwind,android-ia/platform_external_libunwind,bo-on-software/libunwind,CyanogenMod/android_external_libunwind,wdv4758h/libunwind,atanasyan/libunwind-android,joyent/libunwind,project-zerus/libunwind,frida/libunwind,frida/libunwind,olibc/libunwind,geekboxzone/lollipop_external_libunwind,dropbox/libunwind,vegard/libunwind,unkadoug/libunwind,tkelman/libunwind,zeldin/platform_external_libunwind,olibc/libunwind,fillexen/libunwind,android-ia/platform_external_libunwind,fdoray/libunwind,fillexen/libunwind,djwatson/libunwind,atanasyan/libunwind-android,zliu2014/libunwind-tilegx,cms-externals/libunwind,libunwind/libunwind,igprof/libunwind,dropbox/libunwind,geekboxzone/mmallow_external_libunwind,geekboxzone/mmallow_external_libunwind,atanasyan/libunwind,olibc/libunwind,cms-externals/libunwind,vtjnash/libunwind,androidarmv6/android_external_libunwind,mpercy/libunwind,igprof/libunwind,igprof/libunwind,Chilledheart/libunwind,Keno/libunwind,unkadoug/libunwind,tronical/libunwind,DroidSim/platform_external_libunwind,zliu2014/libunwind-tilegx,pathscale/libunwind,djwatson/libunwind,project-zerus/libunwind,fillexen/libunwind,libunwind/libunwind,rntz/libunwind,dreal-deps/libunwind,atanasyan/libunwind-android,Keno/libunwind,krytarowski/libunwind,fdoray/libunwind,rntz/libunwind,SyndicateRogue/libunwind,dreal-deps/libunwind,zliu2014/libunwind-tilegx,mpercy/libunwind,yuyichao/libunwind,cloudius-systems/libunwind,cloudius-systems/libunwind,tony/libunwind,wdv4758h/libunwind,krytarowski/libunwind,rogwfu/libunwind,vtjnash/libunwind,zeldin/platform_external_libunwind,maltek/platform_external_libunwind,CyanogenMod/android_external_libunwind,Chilledheart/libunwind,dagar/libunwind,joyent/libunwind,yuyichao/libunwind,android-ia/platform_external_libunwind,androidarmv6/android_external_libunwind,tkelman/libunwind,geekboxzone/lollipop_external_libunwind,pathscale/libunwind,maltek/platform_external_libunwind,dreal-deps/libunwind,bo-on-software/libunwind