From 6ba512d1d1af17c941934f20aaacda58a07388f6 Mon Sep 17 00:00:00 2001
From: chrchr-github <78114321+chrchr-github@users.noreply.github.com>
Date: Wed, 17 Dec 2025 10:07:11 +0100
Subject: [PATCH 1/3] Update astutils.cpp

---
 lib/astutils.cpp | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/lib/astutils.cpp b/lib/astutils.cpp
index d5d38bc3453..c91f41d9651 100644
--- a/lib/astutils.cpp
+++ b/lib/astutils.cpp
@@ -2943,6 +2943,9 @@ static bool isExpressionChangedAt(const F& getExprTok,
         auto expr = getExprTok();
         if (!expr && !(tok->valueType() && tok->valueType()->pointer == 0 && tok->valueType()->reference == Reference::None))
             aliased = true;
+        if (!aliased && expr && expr->varId() && tok->isCast() && tok->valueType() && tok->valueType()->reference != Reference::None &&
+            Token::Match(tok->astOperand2() ? tok->astOperand2() : tok->astOperand1(), "%varid%", expr->varId()))
+            aliased = true;
         if (!aliased)
             aliased = isAliasOf(tok, expr, &i);
         if (!aliased)

From 81c113e1a43b08dff39780aab0da498cadbcf834 Mon Sep 17 00:00:00 2001
From: chrchr-github <78114321+chrchr-github@users.noreply.github.com>
Date: Wed, 17 Dec 2025 10:08:49 +0100
Subject: [PATCH 2/3] Update testother.cpp

---
 test/testother.cpp | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/test/testother.cpp b/test/testother.cpp
index 6b1ae634d26..8251aec99ca 100644
--- a/test/testother.cpp
+++ b/test/testother.cpp
@@ -3981,6 +3981,19 @@ class TestOther : public TestFixture {
               "    t.s->i = 0;\n"
               "}\n");
         ASSERT_EQUALS("", errout_str());
+
+        check("struct B {};\n" // #13877
+              "struct D : B { int i; };\n"
+              "void f(B& b) {\n"
+              "    static_cast<D&>(b).i = 0;\n"
+              "}\n"
+              "void g(B& b) {\n"
+              "    std::cin >> static_cast<B&>(b).i;\n"
+              "}\n"
+              "int h(B& b) {\n"
+              "    return static_cast<const D&>(b).i;\n"
+              "}\n");
+        ASSERT_EQUALS("[test.cpp:9:10]: (style) Parameter 'b' can be declared as reference to const [constParameterReference]\n", errout_str());
     }
 
     void constParameterCallback() {

From 577e275b181036afa46bcca62393b72b1591c4c8 Mon Sep 17 00:00:00 2001
From: chrchr-github <78114321+chrchr-github@users.noreply.github.com>
Date: Wed, 17 Dec 2025 10:12:27 +0100
Subject: [PATCH 3/3] Update testother.cpp

---
 test/testother.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/testother.cpp b/test/testother.cpp
index 8251aec99ca..c4efdc2c611 100644
--- a/test/testother.cpp
+++ b/test/testother.cpp
@@ -3988,7 +3988,7 @@ class TestOther : public TestFixture {
               "    static_cast<D&>(b).i = 0;\n"
               "}\n"
               "void g(B& b) {\n"
-              "    std::cin >> static_cast<B&>(b).i;\n"
+              "    std::cin >> static_cast<D&>(b).i;\n"
               "}\n"
               "int h(B& b) {\n"
               "    return static_cast<const D&>(b).i;\n"