Fix #14023 FP functionStatic (inconclusive) for const overload (danmar#7679)

Co-authored-by: chrchr-github <noreply@github.com>

Author: chrchr-github

lib/checkclass.cpp

@@ -2189,6 +2189,13 @@ void CheckClass::checkConst()
             const bool suggestStatic = memberAccessed != MemberAccess::MEMBER && !func.isOperator();
             if ((returnsPtrOrRef || func.isConst() || func.hasLvalRefQualifier()) && !suggestStatic)
                 continue;
+            if (suggestStatic && func.isConst()) {
+                const auto overloads = func.getOverloadedFunctions();
+                if (overloads.size() > 1 && std::any_of(overloads.begin(), overloads.end(), [&](const Function* ovl) {
+                    return &func != ovl && func.argCount() == ovl->argCount() && func.argsMatch(ovl->functionScope, ovl->argDef, func.argDef, emptyString, 0);
+                }))
+                    continue;
+            }
 
             std::string classname = scope->className;
             const Scope *nest = scope->nestedIn;

test/testclass.cpp

@@ -190,6 +190,7 @@ class TestClass : public TestFixture {
         TEST_CASE(const97);
         TEST_CASE(const98);
         TEST_CASE(const99);
+        TEST_CASE(const100);
 
         TEST_CASE(const_handleDefaultParameters);
         TEST_CASE(const_passThisToMemberOfOtherClass);
@@ -6855,6 +6856,15 @@ class TestClass : public TestFixture {
         ASSERT_EQUALS("", errout_str());
     }
 
+    void const100() {
+        checkConst("struct S {\n" // #14023
+                   "    void f() { ++i; }\n"
+                   "    void f() const {}\n"
+                   "    int i;\n"
+                   "};\n");
+        ASSERT_EQUALS("", errout_str());
+    }
+
     void const_handleDefaultParameters() {
         checkConst("struct Foo {\n"
                    "    void foo1(int i, int j = 0) {\n"