From 8c729fefa817f4366843d1eb16252e8515a11ea8 Mon Sep 17 00:00:00 2001
From: chrchr-github <78114321+chrchr-github@users.noreply.github.com>
Date: Wed, 21 Feb 2024 21:14:17 +0100
Subject: [PATCH] Fix #12394 FP uninitvar with reference to first array struct
 element (#6008)

---
 lib/astutils.cpp       | 2 +-
 test/testuninitvar.cpp | 8 ++++++++
 2 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/lib/astutils.cpp b/lib/astutils.cpp
index a242352a879..b3a656bdf02 100644
--- a/lib/astutils.cpp
+++ b/lib/astutils.cpp
@@ -2571,7 +2571,7 @@ bool isVariableChanged(const Token *tok, int indirect, const Settings *settings,
     tok2 = skipRedundantPtrOp(tok2, tok2->astParent());
 
     if (tok2->astParent() && tok2->astParent()->isAssignmentOp()) {
-        if ((indirect == 0 || tok2 != tok) && tok2 == tok2->astParent()->astOperand1())
+        if (((indirect == 0 || tok2 != tok) || (indirect == 1 && tok2->str() == ".")) && tok2 == tok2->astParent()->astOperand1())
             return true;
         // Check if assigning to a non-const lvalue
         const Variable * var = getLHSVariable(tok2->astParent());
diff --git a/test/testuninitvar.cpp b/test/testuninitvar.cpp
index cd430663354..2fe099b08f5 100644
--- a/test/testuninitvar.cpp
+++ b/test/testuninitvar.cpp
@@ -6406,6 +6406,14 @@ class TestUninitVar : public TestFixture {
                         "    f(&b);\n"
                         "}\n");
         ASSERT_EQUALS("", errout.str());
+
+        valueFlowUninit("struct S { int x; };\n" // #12394
+                        "int f() {\n"
+                        "    struct S s[1];\n"
+                        "    s->x = 0;\n"
+                        "    return s[0].x;\n"
+                        "}\n");
+        ASSERT_EQUALS("", errout.str());
     }
 
     void valueFlowUninitBreak() { // Do not show duplicate warnings about the same uninitialized value