These are the packages that would be merged, in order:

Calculating dependencies... done!
[ebuild   R   ] media-libs/mesa-7.3-r1  USE="nptl xcb -debug -doc -motif -pic" VIDEO_CARDS="radeon via -intel -mach64 -mga -none -r128 -s3virge -savage -sis (-sunffb) -tdfx -trident" 0 kB

Total: 1 package (1 reinstall), Size of downloads: 0 kB