The manifest produced for buildtools-tarball ends up empty at the moment. It may be because the SDK manifest is only for the target portion and that is expected to be empty for buildtools-tarball, but if you actually want to look at the contents of the host part it looks like there's nowhere you can see that right now.
Module: openembedded-core.git Branch: master Commit: 3069641589942f52b11e88cfea564ebba4beb3c2 URL: http://git.openembedded.org/?p=openembedded-core.git&a=commit;h=3069641589942f52b11e88cfea564ebba4beb3c2
verified on master d4585fa23d56a58c583ee33db067a23177a936b1 I run bitbake buildtools-tarball and obtained here: /home/valentin/yocto/poky/build/tmp/deploy/sdk 3280592 -rw-------. 1 valentin valentin 5089 Sep 14 18:34 poky-glibc-x86_64-buildtools-tarball-i586-buildtools-nativesdk-standalone-1.8+snapshot-20150914.host.manifest 3276801 -rwxr-xr-x. 1 valentin valentin 26902738 Sep 14 18:34 poky-glibc-x86_64-buildtools-tarball-i586-buildtools-nativesdk-standalone-1.8+snapshot-20150914.sh 3280580 -rw-------. 1 valentin valentin 0 Sep 14 18:32 poky-glibc-x86_64-buildtools-tarball-i586-buildtools-nativesdk-standalone-1.8+snapshot-20150914.target.manifest As you observe the target.manifest is empty.
The buildtools isn't a complete SDK, it only contains host tools - therefore the target manifest is expected to be empty. If you want to check the target manifest you will need to look at the output of building a proper SDK (i.e. bitbake -c populate_sdk <imagename>).
Thank you, Paul! 3280393 -rw-------. 1 valentin valentin 85166 Sep 15 13:02 poky-glibc-x86_64-core-image-sato-sdk-i586-toolchain-1.8+snapshot.target.manifest file is ok.