On Mon, Jan 1, 2018 at 11:30 PM, Martin Sebor <mse...@gmail.com> wrote: > PR tree-optimization/83640 - ice in generic_overlap at > gimple-ssa-warn-restrict.c:814 highlights out a class of cases > where the -Wrestrict checker assumes that the range of a pointer > offset that us represented by a VR_RANGE has a lower bound that > is less than its upper bound. The pass asserts that this is so > and cases to the contrary trigger an ICE. > > The submitted test case that triggers this ICE is due to a missed > optimization in tree-ssa-strlen (which could, and IMO should, > guarantee that the offsets it constructs are in such a range, and > I'll submit a separate patch with that change), but the assumption > isn't safe in general for offsets whose range happens to straddle > the PTRDIFF_MAX boundary, i.e., whose lower bound is greater than > its upper bound. > > The attached patch makes adjustments to remove this assumption > and avoid the ICE. Tested on x86_64-linux with no regressions.
Isn't the error you are using HOST_WIDE_INT rather than offset_int for sizrange/ovloff/ovlsiz in builtin_access? > Martin > > PS The patch also removes the same troublesome assertion that's > also removed in the one below: > > https://gcc.gnu.org/ml/gcc-patches/2017-12/msg01399.html
