While emerging mesa-7.8 it stops with an error that libdrm 2.4.19 is needed. The ebuild depends on libdrm 2.4.17. Reproducible: Always Steps to Reproduce: 1. emerge media-libs/mesa-7.8 2. 3.
The ebuild should depend on libdrm-2.4.19
Fixed in CVS by increasing libdrm dependency. Although strictly speaking, it is only needed if you have VIDEO_CARDS="intel" set.