From 493d2048a6df0ad0a433bd989c68f3c1e1cf70b6 Mon Sep 17 00:00:00 2001
From: chrchr <christian.riesch@live.com>
Date: Fri, 8 Apr 2022 17:33:01 +0200
Subject: [PATCH] Fix #10368 FP: unassignedVariable with structured binding

---
 lib/checkunusedvar.cpp |  2 +-
 test/testunusedvar.cpp | 11 +++++++++++
 2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/lib/checkunusedvar.cpp b/lib/checkunusedvar.cpp
index 0118c482e2b..de9430d5d05 100644
--- a/lib/checkunusedvar.cpp
+++ b/lib/checkunusedvar.cpp
@@ -704,7 +704,7 @@ void CheckUnusedVar::checkFunctionVariableUsage_iterateScopes(const Scope* const
                 type = Variables::referenceArray;
             else if (i->isArray())
                 type = (i->dimensions().size() == 1U) ? Variables::array : Variables::pointerArray;
-            else if (i->isReference())
+            else if (i->isReference() && !(i->valueType() && i->valueType()->type == ValueType::UNKNOWN_TYPE && Token::simpleMatch(i->typeStartToken(), "auto")))
                 type = Variables::reference;
             else if (i->nameToken()->previous()->str() == "*" && i->nameToken()->strAt(-2) == "*")
                 type = Variables::pointerPointer;
diff --git a/test/testunusedvar.cpp b/test/testunusedvar.cpp
index 02eaf6af38b..caf81ed8293 100644
--- a/test/testunusedvar.cpp
+++ b/test/testunusedvar.cpp
@@ -217,6 +217,7 @@ class TestUnusedVar : public TestFixture {
         TEST_CASE(localvarAddr); // #7477
         TEST_CASE(localvarDelete);
         TEST_CASE(localvarLambda); // #8941, #8948
+        TEST_CASE(localvarStructuredBinding); // #10368
 
         TEST_CASE(localvarCppInitialization);
         TEST_CASE(localvarCpp11Initialization);
@@ -5995,6 +5996,16 @@ class TestUnusedVar : public TestFixture {
         ASSERT_EQUALS("", errout.str());
     }
 
+
+    void localvarStructuredBinding() {
+        functionVariableUsage("void f() {\n" // #10368
+                              "    std::map<int, double> m;\n"
+                              "    m[2] = 2.0;\n"
+                              "    for (auto& [k, v] : m) {}\n"
+                              "}\n");
+        ASSERT_EQUALS("", errout.str());
+    }
+
     void localvarCppInitialization() {
         functionVariableUsage("void foo() {\n"
                               "    int buf[6];\n"