Fix cppcheck-opensource#1175 uninitialized data: casted to 'int *' and dereferenced

chrchr-github · chrchr-github · commit 811fc0cde01a · 2023-04-24T15:47:02.000+02:00
diff --git a/lib/checkuninitvar.cpp b/lib/checkuninitvar.cpp
@@ -1240,7 +1240,7 @@ const Token* CheckUninitVar::isVariableUsage(bool cpp, const Token *vartok, cons
                 tok = tok->astParent();
         }
         if (Token::simpleMatch(tok->astParent(), "=")) {
-            if (astIsLhs(tok))
+            if (astIsLhs(tok) && (alloc == ARRAY || !derefValue || !derefValue->astOperand1() || !derefValue->astOperand1()->isCast()))
                 return nullptr;
             if (alloc != NO_ALLOC && astIsRhs(valueExpr))
                 return nullptr;
diff --git a/test/testuninitvar.cpp b/test/testuninitvar.cpp
@@ -2049,6 +2049,14 @@ class TestUninitVar : public TestFixture {
                        "    A* a = new A{};\n"
                        "}\n");
         ASSERT_EQUALS("", errout.str());
+
+        // #1175
+        checkUninitVar("void f() {\n"
+                       "    int* p = new int;\n"
+                       "    *((int*)*p) = 42;\n"
+                       "    delete p;\n"
+                       "}\n");
+        ASSERT_EQUALS("[test.cpp:3]: (error) Memory is allocated but not initialized: p\n", errout.str());
     }
 
     // class / struct..

Original file line number	Diff line number	Diff line change
`@@ -1240,7 +1240,7 @@ const Token* CheckUninitVar::isVariableUsage(bool cpp, const Token *vartok, cons`
`1240`	`1240`	`tok = tok->astParent();`
`1241`	`1241`	`}`
`1242`	`1242`	`if (Token::simpleMatch(tok->astParent(), "=")) {`
`1243`		`- if (astIsLhs(tok))`
	`1243`	`+ if (astIsLhs(tok) && (alloc == ARRAY \|\| !derefValue \|\| !derefValue->astOperand1() \|\| !derefValue->astOperand1()->isCast()))`
`1244`	`1244`	`return nullptr;`
`1245`	`1245`	`if (alloc != NO_ALLOC && astIsRhs(valueExpr))`
`1246`	`1246`	`return nullptr;`