I've isolated the offending code fragment
and plugged it in the old boilerplate.c that comes with the mesa sources, and the behaviour is the same:
After 32k triangles (with normals) the 1.0-3123 GLcore library cannot compile the geometry in a display list.
The same executable runs ok on 1.0-2960 (didn't even recompile it)
Do I send this sample code to linux-bugs as well?
(I haven't heard anything on my initial report)