diff --git a/clang/lib/StaticAnalyzer/Checkers/ArrayBoundCheckerV2.cpp b/clang/lib/StaticAnalyzer/Checkers/ArrayBoundCheckerV2.cpp
--- a/clang/lib/StaticAnalyzer/Checkers/ArrayBoundCheckerV2.cpp
+++ b/clang/lib/StaticAnalyzer/Checkers/ArrayBoundCheckerV2.cpp
@@ -222,6 +222,12 @@
   std::tie(RootNonLoc, ConstantFoldedRHS) =
       simplify(SVB, RawOffset.getByteOffset(), Zero);
 
+  // No unsigned symbolic value can be less then a negative constant.
+  if (const auto SymbolicRoot = RootNonLoc.getAs<SymbolVal>())
+    if (SymbolicRoot->getSymbol()->getType()->isUnsignedIntegerType() &&
+        ConstantFoldedRHS.castAs<ConcreteInt>().getValue().isNegative())
+      return State;
+
   NonLoc LowerBoundCheck =
       SVB.evalBinOpNN(State, BO_LT, RootNonLoc.castAs<NonLoc>(),
                       ConstantFoldedRHS.castAs<ConcreteInt>(),
diff --git a/clang/test/Analysis/out-of-bounds-false-positive.c b/clang/test/Analysis/out-of-bounds-false-positive.c
--- a/clang/test/Analysis/out-of-bounds-false-positive.c
+++ b/clang/test/Analysis/out-of-bounds-false-positive.c
@@ -8,12 +8,11 @@
 const char a[] = "abcd"; // extent: 5 bytes
 
 void symbolic_size_t_and_int0(size_t len) {
-  // FIXME: Should not warn for this.
-  (void)a[len + 1]; // expected-warning {{Out of bound memory access}}
+  (void)a[len + 1]; // no-warning
   // We infered that the 'len' must be in a specific range to make the previous indexing valid.
   // len: [0,3]
-  clang_analyzer_eval(len <= 3); // expected - warning {{TRUE}}
-  clang_analyzer_eval(len <= 2); // expected - warning {{UNKNOWN}}
+  clang_analyzer_eval(len <= 3); // expected-warning {{TRUE}}
+  clang_analyzer_eval(len <= 2); // expected-warning {{UNKNOWN}}
 }
 
 void symbolic_size_t_and_int1(size_t len) {