From b7b92b21405bcb96f1b2d6e935091ea8fd01ec99 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Daniel=20Marjam=C3=A4ki?= <daniel.marjamaki@gmail.com>
Date: Sat, 21 May 2016 20:07:35 +0200
Subject: [PATCH] Fixed #6674 (false positive 'unusedPrivateFunction' - calling
 virtual function in subclass)

---
 lib/symboldatabase.cpp      |  4 +++-
 test/testunusedprivfunc.cpp | 18 ++++++++++++++++++
 2 files changed, 21 insertions(+), 1 deletion(-)

diff --git a/lib/symboldatabase.cpp b/lib/symboldatabase.cpp
index 210abbb91..a10c737f7 100644
--- a/lib/symboldatabase.cpp
+++ b/lib/symboldatabase.cpp
@@ -2789,7 +2789,9 @@ bool Function::isImplicitlyVirtual_rec(const ::Type* baseType, bool& safe) const
 
                     // check for matching return parameters
                     while (temp1->str() != "virtual") {
-                        if (temp1->str() != temp2->str()) {
+                        if (temp1->str() != temp2->str() &&
+                            !(temp1->str() == derivedFromType->name() &&
+                              temp2->str() == baseType->name())) {
                             returnMatch = false;
                             break;
                         }
diff --git a/test/testunusedprivfunc.cpp b/test/testunusedprivfunc.cpp
index ff63d565f..c44aaf5fd 100644
--- a/test/testunusedprivfunc.cpp
+++ b/test/testunusedprivfunc.cpp
@@ -481,6 +481,24 @@ private:
               "    void func() {}\n"
               "};");
         ASSERT_EQUALS("", errout.str());
+
+        check("class Base {\n"
+              "public:\n"
+              "    void dostuff() {\n"
+              "      f();\n"
+              "    }\n"
+              "\n"
+              "private:\n"
+              "    virtual Base* f() = 0;\n"
+              "};\n"
+              "\n"
+              "class Derived : public Base {\n"
+              "private:\n"
+              "    Derived* f() {\n"
+              "      return 0;\n"
+              "    }\n"
+              "};");
+        ASSERT_EQUALS("", errout.str());
     }
 
     void friendClass() {