Created attachment 2374 [details]
Data.frame for reproducing bug
With a (very) large number of model terms, the C function termsform in model.c can crash with a SIGSEGV (memory not mapped) error. Yes, the example attached has a maybe unrealistic number of terms / columns, but this should not happen.
To the best of my knowledege model.c has not changed in a year, so I believe this is an unpatched bug? I see previous bug reports referencing stack exhaustion in this function, but I think this is different.
With attached data.frame, code to reproduce is:
tmp <- terms(SamplePrep ~ ., data = intensities)
Thanks for the report. Segfault eliminated in R-devel and R-patched. The example now fails for me with a protect stack overflow. Addressing this would require a more extensive redesign.