[PATCH] D47007: [Sanitizer] CStringChecker fix for strlcpy when no bytes are copied to the dest buffer

[Artem Dergachev via Phabricator via cfe-commits]

NoQ accepted this revision.
NoQ added a comment.
This revision is now accepted and ready to land.

I've been thinking if we could de-duplicate this whole set of branches that computes the return value so that we didn't have to fix every bug twice. Maybe move it to an auxiliary function.



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Comment at: lib/StaticAnalyzer/Checkers/CStringChecker.cpp:1795
     // copied element, or a pointer to the start of the destination buffer.
     Result = (returnEnd ? UnknownVal() : DstVal);
   } else {
----------------
Do we need to consider `returnEnd` on the short path as well?


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Comment at: lib/StaticAnalyzer/Checkers/CStringChecker.cpp:1869-1875
   if (returnPtr) {
     // If this is a stpcpy-style copy, but we were unable to check for a buffer
     // overflow, we still need a result. Conjure a return value.
     if (returnEnd && Result.isUnknown()) {
       Result = svalBuilder.conjureSymbolVal(nullptr, CE, LCtx, C.blockCount());
     }
   }
----------------
Do we need to do that on the short path as well?


Repository:
  rC Clang

https://reviews.llvm.org/D47007