Created attachment 545708 [details] build.log Also does not emerge without LTO on this package, though LTO on a dep may have caused it.
Created attachment 545724 [details] emerge --info
This is due to dev-libs/libaio being compiled with LTO, try re-emerging that package w/o LTO and thin-provisioning-tools should compile successfully.
*** This bug has been marked as a duplicate of bug 630298 ***