On Fri, Dec 05, 2014 at 09:02:46PM +0000, Gary V. Vaughan wrote: > If there's a way to at least diagnose negative arguments rather than silently > change behavior, that would save other projects some migration headaches...
We could diagnose one of the m4 uses of obstack_blank at compile time, but not the one in m4/macro.c:trace_flush which has a non-constant shrink value.. Yes, I agree this can cause some pain, but at least dying with out-of-memory is a loud symptom. The alternative is to do as Paul suggested and make obstack_blank accept a negative length argument, but that would - kill >2G obstacks on 32-bit targets, - lose the nice symmetry with other obstack functions, and obstack_blank_fast is the right interface to use for shrinking. -- Alan Modra Australia Development Lab, IBM
