Fix #14951: FP unreadVariable with function pointer member (#8768)

Author: ludviggunne

lib/tokenize.cpp

@@ -4549,7 +4549,7 @@ static void setVarIdStructMembers(Token *&tok1,
         return;
     }
 
-    while (Token::Match(tok->next(), ")| . %name% !!(")) {
+    while (Token::Match(tok->next(), ")| . %name%")) {
         // Don't set varid for trailing return type
         if (tok->strAt(1) == ")" && Token::Match(tok->linkAt(1)->tokAt(-1), "%name%|]") && !tok->linkAt(1)->tokAt(-1)->isKeyword() &&
             TokenList::isFunctionHead(tok->linkAt(1), "{;")) {
@@ -4571,6 +4571,8 @@ static void setVarIdStructMembers(Token *&tok1,
         std::map<std::string, nonneg int>& members = structMembers[struct_varid];
         const auto it = utils::as_const(members).find(tok->str());
         if (it == members.cend()) {
+            if (Token::Match(tok, "%name% ("))
+                break;
             members[tok->str()] = ++varId;
             tok->varId(varId);
         } else {

test/testsymboldatabase.cpp

@@ -233,6 +233,7 @@ class TestSymbolDatabase : public TestFixture {
         TEST_CASE(rangeBasedFor);
 
         TEST_CASE(memberVar1);
+        TEST_CASE(memberVar2);
         TEST_CASE(arrayMemberVar1);
         TEST_CASE(arrayMemberVar2);
         TEST_CASE(arrayMemberVar3);
@@ -1864,6 +1865,22 @@ class TestSymbolDatabase : public TestFixture {
         ASSERT(Token::simpleMatch(tok->variable()->typeStartToken(), "int x ;"));
     }
 
+    void memberVar2() {
+        GET_SYMBOL_DB( "struct S { void (*fp)(); };\n"
+                       "void g();\n"
+                       "void f() {\n"
+                       "    S s;\n"
+                       "    s.fp = g;\n"
+                       "    s.fp();\n"
+                       "}\n");
+
+        ASSERT(db != nullptr);
+        const Token *fp1 = Token::findsimplematch(tokenizer.tokens(), "fp =");
+        const Token *fp2 = Token::findsimplematch(tokenizer.tokens(), "fp (");
+        ASSERT(fp1->varId());
+        ASSERT_EQUALS(fp2->varId(), fp1->varId());
+    }
+
     void arrayMemberVar1() {
         GET_SYMBOL_DB("struct Foo {\n"
                       "    int x;\n"

test/testunusedvar.cpp

@@ -158,6 +158,7 @@ class TestUnusedVar : public TestFixture {
         TEST_CASE(localvar71);
         TEST_CASE(localvar72);
         TEST_CASE(localvar73);
+        TEST_CASE(localvar74);
         TEST_CASE(localvarloops); // loops
         TEST_CASE(localvaralias1);
         TEST_CASE(localvaralias2); // ticket #1637
@@ -4100,6 +4101,17 @@ class TestUnusedVar : public TestFixture {
         ASSERT_EQUALS("", errout_str());
     }
 
+    void localvar74() {
+        functionVariableUsage("struct S { void (*fp)(); };\n"
+                              "void g();\n"
+                              "void f() {\n"
+                              "    S s;\n"
+                              "    s.fp = g;\n"
+                              "    s.fp();\n"
+                              "}\n");
+        ASSERT_EQUALS("", errout_str());
+    }
+
     void localvarloops() {
         // loops
         functionVariableUsage("void fun(int c) {\n"