cschwan/sage-on-gentoo — comment on commit 4582b3cc12bdf49b34a8efe51579eae123ba30dd
File:  line 0
By kiwifb:

I don't think that's related. During the test sage is trying to compile some code that requires some of these headers and some of the .c file. The c file is the real troubling part since they have been compiled to create some of the shared libraries. You would expect that you compile against the library rather than recompiling the c code.