From 9efedd6be90973ebb9cfd3a83e0ba0ad535ca33a Mon Sep 17 00:00:00 2001
From: chrchr-github <78114321+chrchr-github@users.noreply.github.com>
Date: Fri, 2 Dec 2022 07:21:33 +0100
Subject: [PATCH] Fix #11223 checkLibraryFunction treats "auto" as type (#4605)

* Fix #11223 checkLibraryFunction treats "auto" as type

* Use utility function
---
 lib/token.cpp          | 5 +++++
 test/testfunctions.cpp | 6 ++++++
 2 files changed, 11 insertions(+)

diff --git a/lib/token.cpp b/lib/token.cpp
index 757e75e73..9e829e35c 100644
--- a/lib/token.cpp
+++ b/lib/token.cpp
@@ -2264,6 +2264,11 @@ std::pair<const Token*, const Token*> Token::typeDecl(const Token * tok)
                 if (r.first)
                     return r;
             }
+            if (astIsRangeBasedForDecl(var->nameToken()) && astIsContainer(var->nameToken()->astParent()->astOperand2())) { // range-based for
+                const ValueType* vt = var->nameToken()->astParent()->astOperand2()->valueType();
+                if (vt && vt->containerTypeToken)
+                    return { vt->containerTypeToken, vt->containerTypeToken->linkAt(-1) };
+            }
         }
         return {var->typeStartToken(), var->typeEndToken()->next()};
     } else if (Token::simpleMatch(tok, "return")) {
diff --git a/test/testfunctions.cpp b/test/testfunctions.cpp
index 753c8d4b9..585007362 100644
--- a/test/testfunctions.cpp
+++ b/test/testfunctions.cpp
@@ -1900,6 +1900,12 @@ private:
               "void g() { C::f(); }\n");
         ASSERT_EQUALS("", errout.str());
 
+        check("void f(const std::vector<std::string>& v) {\n" // #11223
+              "    for (const auto& s : v)\n"
+              "        s.find(\"\");\n"
+              "}\n");
+        ASSERT_EQUALS("[test.cpp:3]: (warning) Return value of function s.find() is not used.\n", errout.str());
+
         settings.severity = severity_old;
         settings.checkLibrary = false;
     }