From f8132ea0224b2c03d6342d2d142e00a9b9b9d498 Mon Sep 17 00:00:00 2001
From: Paul Fultz II <pfultz2@yahoo.com>
Date: Tue, 20 Dec 2022 13:29:19 -0600
Subject: [PATCH] Fix 11381: FP derefInvalidIteratorRedundantCheck when
 updating iterator using std::tie (#4659)

---
 lib/astutils.cpp |  3 ++-
 test/teststl.cpp | 11 +++++++++++
 2 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/lib/astutils.cpp b/lib/astutils.cpp
index 0de86bb27..4d3c0f241 100644
--- a/lib/astutils.cpp
+++ b/lib/astutils.cpp
@@ -2361,7 +2361,8 @@ bool isVariableChangedByFunctionCall(const Token *tok, int indirect, const Setti
                 if (indirect > 0 && requireInit && requireNonNull)
                     return true;
             }
-
+            if (Token::simpleMatch(tok->tokAt(-2), "std :: tie"))
+                return true;
             // if the library says 0 is invalid
             // => it is assumed that parameter is an in parameter (TODO: this is a bad heuristic)
             if (indirect == 0 && requireNonNull)
diff --git a/test/teststl.cpp b/test/teststl.cpp
index 5bbaf39b4..a818b4b58 100644
--- a/test/teststl.cpp
+++ b/test/teststl.cpp
@@ -4658,6 +4658,17 @@ private:
               "    return s.end();\n"
               "}\n");
         ASSERT_EQUALS("[test.cpp:3]: (style) Consider using std::find_if algorithm instead of a raw loop.\n", errout.str());
+
+        // #11381
+        check("int f(std::map<int, int>& map) {\n"
+              "    auto it = map.find(1);\n"
+              "    if (it == map.end()) {\n"
+              "        bool bInserted;\n"
+              "        std::tie(it, bInserted) = map.emplace(1, 42);\n"
+              "    }\n"
+              "    return debug_valueflow(it)->second;\n"
+              "}\n");
+        ASSERT_EQUALS("", errout.str());
     }
 
     void dereferenceInvalidIterator2() {