From 200b098471828b751d0a8a1cab7c302a9bb87941 Mon Sep 17 00:00:00 2001
From: chrchr-github <78114321+chrchr-github@users.noreply.github.com>
Date: Mon, 14 Mar 2022 19:15:48 +0100
Subject: [PATCH] Fix #10516 FP for unused private function if address of
 function is taken (#3901)

---
 lib/checkclass.cpp          |  2 +-
 lib/symboldatabase.cpp      | 11 ++++++++---
 test/testunusedprivfunc.cpp | 27 +++++++++++++++++++++++++++
 3 files changed, 36 insertions(+), 4 deletions(-)

diff --git a/lib/checkclass.cpp b/lib/checkclass.cpp
index e4cd3842f..54dad5402 100644
--- a/lib/checkclass.cpp
+++ b/lib/checkclass.cpp
@@ -1177,7 +1177,7 @@ static bool checkFunctionUsage(const Function *privfunc, const Scope* scope)
 
     for (const Variable &var : scope->varlist) {
         if (var.isStatic()) {
-            const Token* tok = Token::findmatch(scope->bodyEnd, "%varid% =|(|{", var.declarationId());
+            const Token* tok = Token::findmatch(scope->bodyStart, "%varid% =|(|{", var.declarationId());
             if (tok)
                 tok = tok->tokAt(2);
             while (tok && tok->str() != ";") {
diff --git a/lib/symboldatabase.cpp b/lib/symboldatabase.cpp
index 871d67cda..eff2d762b 100644
--- a/lib/symboldatabase.cpp
+++ b/lib/symboldatabase.cpp
@@ -1081,7 +1081,7 @@ void SymbolDatabase::createSymbolDatabaseSetFunctionPointers(bool firstPass)
 
     // Set function call pointers
     for (const Token* tok = mTokenizer->list.front(); tok != mTokenizer->list.back(); tok = tok->next()) {
-        if (tok->isName() && !tok->function() && tok->varId() == 0 && Token::Match(tok, "%name% [(,)>]") && !isReservedName(tok->str())) {
+        if (tok->isName() && !tok->function() && tok->varId() == 0 && Token::Match(tok, "%name% [(,)>;]") && !isReservedName(tok->str())) {
             if (tok->next()->str() == ">" && !tok->next()->link())
                 continue;
 
@@ -1089,7 +1089,7 @@ void SymbolDatabase::createSymbolDatabaseSetFunctionPointers(bool firstPass)
                 const Token *start = tok;
                 while (Token::Match(start->tokAt(-2), "%name% ::"))
                     start = start->tokAt(-2);
-                if (!Token::Match(start->previous(), "[(,<]") && !Token::Match(start->tokAt(-2), "[(,<] &"))
+                if (!Token::Match(start->previous(), "[(,<=]") && !Token::Match(start->tokAt(-2), "[(,<=] &") && !Token::Match(start, "%name% ;"))
                     continue;
             }
 
@@ -5352,8 +5352,13 @@ const Function* SymbolDatabase::findFunction(const Token *tok) const
                 else
                     tok1 = nullptr;
 
-                if (tok1)
+                if (tok1) {
+                    const Function* func = currScope->findFunction(tok1);
+                    if (func)
+                        return func;
+
                     currScope = currScope->findRecordInNestedList(tok1->str());
+                }
             }
 
             if (tok1)
diff --git a/test/testunusedprivfunc.cpp b/test/testunusedprivfunc.cpp
index 34f022a1b..e868374ef 100644
--- a/test/testunusedprivfunc.cpp
+++ b/test/testunusedprivfunc.cpp
@@ -55,6 +55,7 @@ private:
         TEST_CASE(func_pointer4); // ticket #2807
         TEST_CASE(func_pointer5); // ticket #2233
         TEST_CASE(func_pointer6); // ticket #4787
+        TEST_CASE(func_pointer7); // ticket #10516
 
         TEST_CASE(ctor);
         TEST_CASE(ctor2);
@@ -349,6 +350,32 @@ private:
         ASSERT_EQUALS("", errout.str());
     }
 
+    void func_pointer7() { // #10516
+        check("class C {\n"
+              "    static void f() {}\n"
+              "    static constexpr void(*p)() = f;\n"
+              "};\n");
+        ASSERT_EQUALS("", errout.str());
+
+        check("class C {\n"
+              "    static void f() {}\n"
+              "    static constexpr void(*p)() = &f;\n"
+              "};\n");
+        ASSERT_EQUALS("", errout.str());
+
+        check("class C {\n"
+              "    static void f() {}\n"
+              "    static constexpr void(*p)() = C::f;\n"
+              "};\n");
+        ASSERT_EQUALS("", errout.str());
+
+        check("class C {\n"
+              "    static void f() {}\n"
+              "    static constexpr void(*p)() = &C::f;\n"
+              "};\n");
+        ASSERT_EQUALS("", errout.str());
+    }
+
 
     void ctor() {
         check("class PrivateCtor\n"