[PATCH] D61136: [Analyzer] IteratorChecker - Ensure end()>=begin() and refactor begin and end symbol creation

[Artem Dergachev via Phabricator via cfe-commits]

NoQ added a comment.

Aha, yup, thx!

Do you plan to centralize other code paths on which you conjure symbols?

'Cause i still believe that given that we now support C++ (our prvalues are now properly materialized) (most of the time), you should be able to remove support for symbol-like iterators, and then replace your position symbols with `SymbolMetadata`.



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Comment at: lib/StaticAnalyzer/Checkers/IteratorChecker.cpp:1929-1930
+
+  auto &SymMgr = State->getSymbolManager();
+  auto Sym = SymMgr.conjureSymbol(E, LCtx, T, BlockCount, "end");
+  State = assumeNoOverflow(State, Sym, 4);
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This is a bit more `auto` than allowed by [[ https://llvm.org/docs/CodingStandards.html#use-auto-type-deduction-to-make-code-more-readable | our coding standards ]] (it pretty much disallows `auto` unless it's some sort of `dyn_cast` (`getAs`) or an iterator.


================
Comment at: lib/StaticAnalyzer/Checkers/IteratorChecker.cpp:2247
 
+ProgramStateRef ensureNonNegativeDiff(ProgramStateRef State, SymbolRef Sym1,
+                                      SymbolRef Sym2) {
----------------
This looks like a new feature. Is it testable?


Repository:
  rC Clang

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  https://reviews.llvm.org/D61136/new/

https://reviews.llvm.org/D61136