diff --git a/lib/valueflow.cpp b/lib/valueflow.cpp
index e649786fb8f..f3df5a0c31f 100644
--- a/lib/valueflow.cpp
+++ b/lib/valueflow.cpp
@@ -6707,13 +6707,15 @@ static void valueFlowContainerSize(const TokenList& tokenlist,
                 for (const ValueFlow::Value& value : values)
                     setTokenValue(tok, value, settings);
             }
-            else if (Token::Match(tok->previous(), ",|( {")) {
+            else if (Token::Match(tok->previous(), ",|( {|%str%")) {
                 int nArg{};
                 if (const Token* funcTok = getTokenArgumentFunction(tok, nArg)) {
                     if (const Function* func = funcTok->function()) {
                         if (const Variable* var = func->getArgumentVar(nArg)) {
                             if (var->valueType() && var->valueType()->container && var->valueType()->container->size_templateArgNo < 0) {
-                                std::vector<ValueFlow::Value> values = getInitListSize(tok, var->valueType(), settings, true);
+                                auto values = tok->tokType() == Token::Type::eString
+                                   ? std::vector<ValueFlow::Value>{makeContainerSizeValue(Token::getStrLength(tok))}
+                                   : getInitListSize(tok, var->valueType(), settings, true);
                                 ValueFlow::Value tokValue;
                                 tokValue.valueType = ValueFlow::Value::ValueType::TOK;
                                 tokValue.tokvalue = tok;
diff --git a/test/teststl.cpp b/test/teststl.cpp
index ec6f46148a8..2c4669dbeca 100644
--- a/test/teststl.cpp
+++ b/test/teststl.cpp
@@ -967,6 +967,11 @@ class TestStl : public TestFixture {
                     "}\n");
         ASSERT_EQUALS("[test.cpp:2:17]: error: Out of bounds access in expression 'v[0]' because 'v' is empty. [containerOutOfBounds]\n",
                       errout_str());
+
+        checkNormal("bool f(const std::string_view s) { return s[500] == 'x'; }\n" // #12046
+                    "bool g() { return f(\" \"); }\n");
+        ASSERT_EQUALS("[test.cpp:1:44]: error: Out of bounds access in 's[500]', if 's' size is 1 and '500' is 500 [containerOutOfBounds]\n",
+                      errout_str());
     }
 
     void outOfBoundsSymbolic()