https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113314
Saksham Gupta <io.sakshamgupta at gmail dot com> changed:
What |Removed |Added
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CC| |io.sakshamgupta at gmail dot
com
--- Comment #8 from Saksham Gupta <io.sakshamgupta at gmail dot com> ---
Hi David,
I submitted the CPython GSoC proposal a few months back. I'd like to take a
look at this bug to get more familiar with the core analyzer.
Looking at the trace, the region model is caching fdtab[fd].update.next and
ignoring external mutation. We presumably need to teach the analyzer to drop
those assumptions in two cases:
• volatile memory: If the region has a volatile qualifier (as Drea noted),
we shouldn't trust the cached value.
• Atomics: If the function contains __atomic builtins, it implies a
multi-threaded context, so shared memory might mutate between iterations.
For the volatile case, would the right approach be to intercept this in
region_model::get_rvalue and just return an unknown sval? Or should the
invalidation happen directly inside the infinite-loop checker?
