Hi Linus, not sure whom to address on this issue.
I have built Linux v4.9-rc1, v4.8.2 and v4.4.25 kernels (in this order) this morning. Building a Linux v4.8.2 under Linux v4.9-rc1 took two times longer. As usually I build with 2 parallel-make-jobs. This takes approx. 30mins. Under Linux v4.9-rc1 it took approx. an hour. My system is a Ubuntu/precise AMD64 (WUBI installation). I use my normal build-environment. If you need further informations, please let me know. Regards, - Sedat - P.S.: Listing content of attached tarball file. $ LC_ALL=C ls -R .: build-time configs scripts toolchain-amd64 ./build-time: ls-alt_building-4-4-25-under-4-8-2.txt ls-alt_building-4-8-2-under-4-9-0-rc1.txt ./configs: WHATS-IN-DILEKS-LINUX-KERNEL.txt config-4.4.25-1-iniza-small config-4.8.2-1-iniza-small config-4.9.0-rc1-1-iniza-small ./scripts: build_linux-upstream.sh ./toolchain-amd64: HOST-AND-BUILD-TOOLCHAIN.txt
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