You may have seen this warning from the memory consumption tester: http://gcc.gnu.org/ml/gcc-regression/2008-05/msg00041.html
... related to the recent identifier GC patch. I looked into this a little. My theory is that this is an artifact of how the tester collects its data. In particular I suspect the tester was not including the identifier data in its memory stats -- but now, because identifiers are allocated via the GC, they are included. If this theory is in error, let me know and I will investigate some more. In this case, it would be helpful to have the script that generates the report. Tom