[PATCH] D46944: [analyzer] Use sufficiently large types for index/size calculation.

[Aleksei Sidorin via Phabricator via cfe-commits]

a.sidorin added inline comments.


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Comment at: lib/StaticAnalyzer/Core/RegionStore.cpp:1344
   // This is a signed value, since it's used in arithmetic with signed indices.
-  return svalBuilder.makeIntVal(RegionSize / EleSize, false);
+  return svalBuilder.makeIntVal(RegionSize / EleSize, Ctx.getSignedSizeType());
 }
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ebevhan wrote:
> a.sidorin wrote:
> > I think we should initialize SValBuilder::ArrayIndexTy with getSignedSizeType() instead of LongLongTy and use `svalBuilder.getArrayIndexType()` here instead.
> I made the change, but it caused a spurious out of bounds warning in index-type.c for the 32-bit case. Making the type signed means that anything above MAX/2 will break, and the test uses arrays of that size.
Hm, yes. ssize_t is 32-bit on 32-bit targets but our indices can exceed it. Even if so, `svalBuilder.getArrayIndexType()` should be fine.


Repository:
  rC Clang

https://reviews.llvm.org/D46944