Fix 13665: FP uninitvar for struct reference and arrow operator (danmar#7398)

Author: pfultz2

lib/checkmemoryleak.cpp

@@ -856,7 +856,7 @@ void CheckMemoryLeakStructMember::checkStructVariable(const Variable* const vari
 
                 else if (tok3->str() == "}") {
                     if (indentlevel3 == 0) {
-                        memoryLeak(tok3, variable->name() + "." + assignToks.first->str(), allocType);
+                        memoryLeak(tok3, variable->name() + "." + tok2->strAt(2), allocType);
                         break;
                     }
                     --indentlevel3;

lib/checkuninitvar.cpp

@@ -1667,7 +1667,8 @@ void CheckUninitVar::valueFlowUninit()
                     const bool deref = CheckNullPointer::isPointerDeRef(tok, unknown, *mSettings);
                     uninitderef = deref && v->indirect == 0;
                     const bool isleaf = isLeafDot(tok) || uninitderef;
-                    if (!isleaf && Token::Match(tok->astParent(), ". %name%") && (tok->astParent()->next()->varId() || tok->astParent()->next()->isEnumerator()))
+                    if (!isleaf && Token::Match(tok->astParent(), ". %name%") &&
+                        (tok->astParent()->next()->variable() || tok->astParent()->next()->isEnumerator()))
                         continue;
                 }
                 const ExprUsage usage = getExprUsage(tok, v->indirect, *mSettings);

lib/tokenize.cpp

@@ -3547,8 +3547,17 @@ void Tokenizer::combineOperators()
                 tok->deleteNext();
             }
         } else if (tok->str() == "->") {
-            tok->str(".");
-            tok->originalName("->");
+            // If the preceding sequence is "( & %name% )", replace it by "%name%"
+            Token* t = tok->tokAt(-4);
+            if (Token::Match(t, "( & %name% )") && !Token::simpleMatch(t->previous(), ">")) {
+                t->deleteThis();
+                t->deleteThis();
+                t->deleteNext();
+                tok->str(".");
+            } else {
+                tok->str(".");
+                tok->originalName("->");
+            }
         }
     }
 }

test/cfg/bsd.c

@@ -72,7 +72,7 @@ ssize_t nullPointer_pwritev(int fd, const struct iovec *iov, int iovcnt, off_t o
     return pwritev(fd,iov,iovcnt,offset);
 }
 
-// #9346
+// False negative: #9346
 void uninitvar_timercmp(struct timeval t)
 {
     struct timeval uninit;

test/cfg/posix.c

@@ -1389,7 +1389,7 @@ void uninitvar_types(void)
     b + 1;
 
     struct dirent d;
-    // cppcheck-suppress constStatement - TODO: uninitvar
+    // cppcheck-suppress [uninitvar,constStatement]
     d.d_ino + 1;
 }
 

test/testuninitvar.cpp

@@ -7632,6 +7632,22 @@ class TestUninitVar : public TestFixture {
                         "    S s{ d };\n"
                         "}\n");
         ASSERT_EQUALS("[test.cpp:7]: (error) Uninitialized variable: d\n", errout_str());
+
+        valueFlowUninit("struct S { int x; int y; };\n"
+                        "int f() {\n"
+                        "  S s;\n"
+                        "  s.x = 0;\n"
+                        "  return (&s)->x;\n"
+                        "}\n");
+        ASSERT_EQUALS("", errout_str());
+
+        valueFlowUninit("struct S { int x; int y; };\n"
+                        "int f() {\n"
+                        "  S s;\n"
+                        "  s.x = 0;\n"
+                        "  return (&s)->y;\n"
+                        "}\n");
+        ASSERT_EQUALS("[test.cpp:5]: (error) Uninitialized variable: s.y\n", errout_str());
     }
 
     void valueFlowUninitForLoop()

test/testvarid.cpp

@@ -523,7 +523,7 @@ class TestVarID : public TestFixture {
 
         const char expected[] = "1: struct S { int i@1 ; } ;\n"
                                 "2: int f ( S s@2 ) {\n"
-                                "3: return ( & s@2 ) . i@3 ;\n"
+                                "3: return s@2 . i@3 ;\n"
                                 "4: }\n";
 
         ASSERT_EQUALS(expected, actual);