From 72a36172aa569979f62842c9bddaa068474a5f6e Mon Sep 17 00:00:00 2001
From: chrchr-github <78114321+chrchr-github@users.noreply.github.com>
Date: Sat, 4 Nov 2023 13:40:06 +0100
Subject: [PATCH] Fix  #12142 FP uninitStructMember, unreadVariable with
 pointer to member (#5618)

---
 lib/checkuninitvar.cpp |  5 +++++
 lib/fwdanalysis.cpp    |  2 ++
 test/testuninitvar.cpp |  9 +++++++++
 test/testunusedvar.cpp | 12 ++++++++++++
 4 files changed, 28 insertions(+)

diff --git a/lib/checkuninitvar.cpp b/lib/checkuninitvar.cpp
index 98a39768c..e0c8b7db6 100644
--- a/lib/checkuninitvar.cpp
+++ b/lib/checkuninitvar.cpp
@@ -697,6 +697,11 @@ bool CheckUninitVar::checkScopeForVariable(const Token *tok, const Variable& var
             return true;
         }
 
+        // bailout if there is a pointer to member
+        if (Token::Match(tok, "%varid% . *", var.declarationId())) {
+            return true;
+        }
+
         if (tok->str() == "?") {
             if (!tok->astOperand2())
                 return true;
diff --git a/lib/fwdanalysis.cpp b/lib/fwdanalysis.cpp
index f2431fce3..1dd44759d 100644
--- a/lib/fwdanalysis.cpp
+++ b/lib/fwdanalysis.cpp
@@ -500,6 +500,8 @@ bool FwdAnalysis::possiblyAliased(const Token *expr, const Token *startToken) co
 {
     if (expr->isUnaryOp("*") && !expr->astOperand1()->isUnaryOp("&"))
         return true;
+    if (Token::simpleMatch(expr, ". *"))
+        return true;
 
     const bool macro = false;
     const bool pure = false;
diff --git a/test/testuninitvar.cpp b/test/testuninitvar.cpp
index 645caf390..0bd66b5cb 100644
--- a/test/testuninitvar.cpp
+++ b/test/testuninitvar.cpp
@@ -4875,6 +4875,15 @@ private:
                        "    return s;\n"
                        "}");
         ASSERT_EQUALS("", errout.str());
+
+        checkUninitVar("struct S { int i; };\n" // #12142
+                       "int f() {\n"
+                       "    S s;\n"
+                       "    int S::* p = &S::i;\n"
+                       "    s.*p = 123;\n"
+                       "    return s.i;\n"
+                       "}\n");
+        ASSERT_EQUALS("", errout.str());
     }
 
     void uninitvar2_while() {
diff --git a/test/testunusedvar.cpp b/test/testunusedvar.cpp
index 8f6833625..57ce5632f 100644
--- a/test/testunusedvar.cpp
+++ b/test/testunusedvar.cpp
@@ -201,6 +201,7 @@ private:
         TEST_CASE(localvarStruct11); // 10095
         TEST_CASE(localvarStruct12); // #10495
         TEST_CASE(localvarStruct13); // #10398
+        TEST_CASE(localvarStruct14);
         TEST_CASE(localvarStructArray);
         TEST_CASE(localvarUnion1);
 
@@ -5330,6 +5331,17 @@ private:
         ASSERT_EQUALS("", errout.str());
     }
 
+    void localvarStruct14() { // #12142
+        functionVariableUsage("struct S { int i; };\n"
+                              "int f() {\n"
+                              "    S s;\n"
+                              "    int S::* p = &S::i;\n"
+                              "    s.*p = 123;\n"
+                              "    return s.i;\n"
+                              "}\n");
+        ASSERT_EQUALS("", errout.str());
+    }
+
     void localvarStructArray() {
         // extracttests.start: struct X {int a;};