From 31359075a8d02a5b647074f2d861a0ef40905216 Mon Sep 17 00:00:00 2001
From: Paul <pfultz2@yahoo.com>
Date: Tue, 9 Apr 2024 18:28:52 -0500
Subject: [PATCH] Fix 12600: FP returnDanglingLifetime with smart pointer
 member (regression)

---
 lib/astutils.cpp           | 20 +++++++++++++-------
 test/testautovariables.cpp |  7 +++++++
 2 files changed, 20 insertions(+), 7 deletions(-)

diff --git a/lib/astutils.cpp b/lib/astutils.cpp
index 7bf42b5a493..1e3fd75aedd 100644
--- a/lib/astutils.cpp
+++ b/lib/astutils.cpp
@@ -653,16 +653,23 @@ const Token* getParentLifetime(const Token* tok, const Library* library)
         return tok;
     // If any of the submembers are borrowed types then stop
     if (std::any_of(it.base() - 1, members.cend() - 1, [&](const Token* tok2) {
-        if (astIsPointer(tok2) || astIsContainerView(tok2) || astIsIterator(tok2))
+        const Token* obj = tok2;
+        if(Token::simpleMatch(obj, "["))
+            obj = tok2->astOperand1();
+        const Variable* var = obj->variable();
+        // Check for arrays first since astIsPointer will return true, but an array is not a borrowed type
+        if(var && var->isArray())
+            return false;
+        if (astIsPointer(obj) || astIsContainerView(obj) || astIsIterator(obj))
             return true;
-        if (!astIsUniqueSmartPointer(tok2)) {
-            if (astIsSmartPointer(tok2))
+        if (!astIsUniqueSmartPointer(obj)) {
+            if (astIsSmartPointer(obj))
                 return true;
-            const Token* dotTok = tok2->next();
+            const Token* dotTok = obj->next();
             if (!Token::simpleMatch(dotTok, ".")) {
-                const Token* endTok = nextAfterAstRightmostLeaf(tok2);
+                const Token* endTok = nextAfterAstRightmostLeaf(obj);
                 if (!endTok)
-                    dotTok = tok2->next();
+                    dotTok = obj->next();
                 else if (Token::simpleMatch(endTok, "."))
                     dotTok = endTok;
                 else if (Token::simpleMatch(endTok->next(), "."))
@@ -672,7 +679,6 @@ const Token* getParentLifetime(const Token* tok, const Library* library)
             if (Token::simpleMatch(dotTok, ".") && dotTok->originalName() == "->")
                 return true;
         }
-        const Variable* var = tok2->variable();
         return var && var->isReference();
     }))
         return nullptr;
diff --git a/test/testautovariables.cpp b/test/testautovariables.cpp
index ef8cd776a2b..bdceb1a7616 100644
--- a/test/testautovariables.cpp
+++ b/test/testautovariables.cpp
@@ -3063,6 +3063,13 @@ class TestAutoVariables : public TestFixture {
         ASSERT_EQUALS(
             "[test.cpp:4] -> [test.cpp:3] -> [test.cpp:4]: (error) Returning pointer to local variable 'ptr' that will be invalid when returning.\n",
             errout_str());
+
+        // #12600
+        check("struct S { std::unique_ptr<int> p; };\n"
+              "int* f(const S* s) {\n"
+              "    return s[0].p.get();\n"
+              "}\n");
+        ASSERT_EQUALS("", errout_str());
     }
     void danglingLifetime() {
         check("auto f() {\n"