Declarations2 cpp misra 2023

c/cert/src/rules/DCL40-C/IncompatibleFunctionDeclarations.ql

@@ -21,42 +21,11 @@
 
 import cpp
 import codingstandards.c.cert
-import codingstandards.cpp.types.Compatible
-import ExternalIdentifiers
+import codingstandards.cpp.rules.incompatiblefunctiondeclaration.IncompatibleFunctionDeclaration
 
-predicate interestedInFunctions(
-  FunctionDeclarationEntry f1, FunctionDeclarationEntry f2, ExternalIdentifiers d
-) {
-  not f1 = f2 and
-  d = f1.getDeclaration() and
-  d = f2.getDeclaration()
+module IncompatibleFunctionDeclarationsCppConfig implements IncompatibleFunctionDeclarationConfigSig
+{
+  Query getQuery() { result = Declarations2Package::incompatibleFunctionDeclarationsQuery() }
 }
 
-predicate interestedInFunctions(FunctionDeclarationEntry f1, FunctionDeclarationEntry f2) {
-  interestedInFunctions(f1, f2, _)
-}
-
-module FuncDeclEquiv =
-  FunctionDeclarationTypeEquivalence<TypesCompatibleConfig, interestedInFunctions/2>;
-
-from ExternalIdentifiers d, FunctionDeclarationEntry f1, FunctionDeclarationEntry f2
-where
-  not isExcluded(f1, Declarations2Package::incompatibleFunctionDeclarationsQuery()) and
-  not isExcluded(f2, Declarations2Package::incompatibleFunctionDeclarationsQuery()) and
-  interestedInFunctions(f1, f2, d) and
-  (
-    //return type check
-    not FuncDeclEquiv::equalReturnTypes(f1, f2)
-    or
-    //parameter type check
-    not FuncDeclEquiv::equalParameterTypes(f1, f2)
-  ) and
-  // Apply ordering on start line, trying to avoid the optimiser applying this join too early
-  // in the pipeline
-  exists(int f1Line, int f2Line |
-    f1.getLocation().hasLocationInfo(_, f1Line, _, _, _) and
-    f2.getLocation().hasLocationInfo(_, f2Line, _, _, _) and
-    f1Line >= f2Line
-  )
-select f1, "The object $@ is not compatible with re-declaration $@", f1, f1.getName(), f2,
-  f2.getName()
+import IncompatibleFunctionDeclaration<IncompatibleFunctionDeclarationsCppConfig>

c/cert/src/rules/DCL40-C/IncompatibleObjectDeclarations.ql

@@ -20,16 +20,10 @@
 
 import cpp
 import codingstandards.c.cert
-import ExternalIdentifiers
+import codingstandards.cpp.rules.incompatibleobjectdeclaration.IncompatibleObjectDeclaration
 
-from VariableDeclarationEntry decl1, VariableDeclarationEntry decl2
-where
-  not isExcluded(decl1, Declarations2Package::incompatibleObjectDeclarationsQuery()) and
-  not isExcluded(decl2, Declarations2Package::incompatibleObjectDeclarationsQuery()) and
-  not decl1.getUnspecifiedType() = decl2.getUnspecifiedType() and
-  decl1.getDeclaration() instanceof ExternalIdentifiers and
-  decl2.getDeclaration() instanceof ExternalIdentifiers and
-  decl1.getLocation().getStartLine() >= decl2.getLocation().getStartLine() and
-  decl1.getVariable().getName() = decl2.getVariable().getName()
-select decl1, "The object $@ is not compatible with re-declaration $@", decl1, decl1.getName(),
-  decl2, decl2.getName()
+module IncompatibleObjectDeclarationsCppConfig implements IncompatibleObjectDeclarationConfigSig {
+  Query getQuery() { result = Declarations2Package::incompatibleObjectDeclarationsQuery() }
+}
+
+import IncompatibleObjectDeclaration<IncompatibleObjectDeclarationsCppConfig>

c/cert/test/rules/DCL40-C/IncompatibleFunctionDeclarations.testref

@@ -0,0 +1 @@
+c/common/test/rules/incompatiblefunctiondeclaration/IncompatibleFunctionDeclaration.ql

c/cert/test/rules/DCL40-C/IncompatibleObjectDeclarations.testref

@@ -0,0 +1 @@
+c/common/test/rules/incompatibleobjectdeclaration/IncompatibleObjectDeclaration.ql

c/common/test/rules/incompatiblefunctiondeclaration/IncompatibleFunctionDeclaration.expected

@@ -0,0 +1,4 @@
+| test1.c:1:12:1:12 | declaration of f | The object is not compatible with a re-declaration $@. | test.c:1:6:1:6 | definition of f | f |
+| test.c:1:6:1:6 | definition of f | The object is not compatible with a re-declaration $@. | test1.c:1:12:1:12 | declaration of f | f |
+| test.c:5:6:5:7 | declaration of f1 | The object is not compatible with a re-declaration $@. | test1.c:2:13:2:14 | declaration of f1 | f1 |
+| test.c:6:6:6:7 | definition of f2 | The object is not compatible with a re-declaration $@. | test1.c:3:6:3:7 | definition of f2 | f2 |

c/common/test/rules/incompatiblefunctiondeclaration/IncompatibleFunctionDeclaration.ql

@@ -0,0 +1,8 @@
+// GENERATED FILE - DO NOT MODIFY
+import codingstandards.cpp.rules.incompatiblefunctiondeclaration.IncompatibleFunctionDeclaration
+
+module TestFileConfig implements IncompatibleFunctionDeclarationConfigSig {
+  Query getQuery() { result instanceof TestQuery }
+}
+
+import IncompatibleFunctionDeclaration<TestFileConfig>

c/cert/test/rules/DCL40-C/test.c → c/common/test/rules/incompatiblefunctiondeclaration/test.c

@@ -1,6 +1,3 @@
-short i;                // NON_COMPLIANT
-int a[] = {1, 2, 3, 4}; // NON_COMPLIANT
-
 long f(int a) { // NON_COMPLIANT
   return a * 2;
 }

c/cert/test/rules/DCL40-C/test1.c → c/common/test/rules/incompatiblefunctiondeclaration/test1.c

@@ -1,6 +1,3 @@
-extern int *a; // NON_COMPLIANT
-extern int i;  // NON_COMPLIANT
-
 extern int f(int a);   // NON_COMPLIANT
 extern void f1(int a); // NON_COMPLIANT
 void f2(int a, ...) {} // NON_COMPLIANT

c/common/test/rules/incompatibleobjectdeclaration/IncompatibleObjectDeclaration.expected

@@ -0,0 +1,2 @@
+| test1.c:2:12:2:12 | declaration of i | The object is not compatible with a re-declaration $@. | test.c:1:7:1:7 | definition of i | i |
+| test.c:2:5:2:5 | definition of a | The object is not compatible with a re-declaration $@. | test1.c:1:13:1:13 | declaration of a | a |

c/common/test/rules/incompatibleobjectdeclaration/IncompatibleObjectDeclaration.ql

@@ -0,0 +1,8 @@
+// GENERATED FILE - DO NOT MODIFY
+import codingstandards.cpp.rules.incompatibleobjectdeclaration.IncompatibleObjectDeclaration
+
+module TestFileConfig implements IncompatibleObjectDeclarationConfigSig {
+  Query getQuery() { result instanceof TestQuery }
+}
+
+import IncompatibleObjectDeclaration<TestFileConfig>

c/common/test/rules/incompatibleobjectdeclaration/test.c

@@ -0,0 +1,2 @@
+short i;                // NON_COMPLIANT
+int a[] = {1, 2, 3, 4}; // NON_COMPLIANT

c/common/test/rules/incompatibleobjectdeclaration/test1.c

@@ -0,0 +1,2 @@
+extern int *a; // NON_COMPLIANT
+extern int i;  // NON_COMPLIANT

change_notes/2026-03-27-update-compatible-objects-DCL40-C.md

@@ -0,0 +1,2 @@
+ - `DCL40-C` - `IncompatibleObjectDeclarations.ql`:
+   - The rule now is capable to detect equivalence based on compatible types instead of exact types (which was what it was previously checking on objects). This will eliminate false positives for some array types and types using equivalent typedefs.

cpp/common/src/codingstandards/cpp/exclusions/cpp/Declarations2.qll

@@ -0,0 +1,61 @@
+//** THIS FILE IS AUTOGENERATED, DO NOT MODIFY DIRECTLY.  **/
+import cpp
+import RuleMetadata
+import codingstandards.cpp.exclusions.RuleMetadata
+
+newtype Declarations2Query =
+  TIncompatibleObjectDeclarationsCppQuery() or
+  TIncompatibleFunctionDeclarationsCppQuery() or
+  TLocalVariableStaticStorageDurationQuery()
+
+predicate isDeclarations2QueryMetadata(Query query, string queryId, string ruleId, string category) {
+  query =
+    // `Query` instance for the `incompatibleObjectDeclarationsCpp` query
+    Declarations2Package::incompatibleObjectDeclarationsCppQuery() and
+  queryId =
+    // `@id` for the `incompatibleObjectDeclarationsCpp` query
+    "cpp/misra/incompatible-object-declarations-cpp" and
+  ruleId = "RULE-6-2-2" and
+  category = "required"
+  or
+  query =
+    // `Query` instance for the `incompatibleFunctionDeclarationsCpp` query
+    Declarations2Package::incompatibleFunctionDeclarationsCppQuery() and
+  queryId =
+    // `@id` for the `incompatibleFunctionDeclarationsCpp` query
+    "cpp/misra/incompatible-function-declarations-cpp" and
+  ruleId = "RULE-6-2-2" and
+  category = "required"
+  or
+  query =
+    // `Query` instance for the `localVariableStaticStorageDuration` query
+    Declarations2Package::localVariableStaticStorageDurationQuery() and
+  queryId =
+    // `@id` for the `localVariableStaticStorageDuration` query
+    "cpp/misra/local-variable-static-storage-duration" and
+  ruleId = "RULE-6-7-1" and
+  category = "required"
+}
+
+module Declarations2Package {
+  Query incompatibleObjectDeclarationsCppQuery() {
+    //autogenerate `Query` type
+    result =
+      // `Query` type for `incompatibleObjectDeclarationsCpp` query
+      TQueryCPP(TDeclarations2PackageQuery(TIncompatibleObjectDeclarationsCppQuery()))
+  }
+
+  Query incompatibleFunctionDeclarationsCppQuery() {
+    //autogenerate `Query` type
+    result =
+      // `Query` type for `incompatibleFunctionDeclarationsCpp` query
+      TQueryCPP(TDeclarations2PackageQuery(TIncompatibleFunctionDeclarationsCppQuery()))
+  }
+
+  Query localVariableStaticStorageDurationQuery() {
+    //autogenerate `Query` type
+    result =
+      // `Query` type for `localVariableStaticStorageDuration` query
+      TQueryCPP(TDeclarations2PackageQuery(TLocalVariableStaticStorageDurationQuery()))
+  }
+}

cpp/common/src/codingstandards/cpp/exclusions/cpp/RuleMetadata.qll

@@ -33,6 +33,7 @@ import DeadCode8
 import DeadCode9
 import Declarations
 import Declarations1
+import Declarations2
 import ExceptionSafety
 import Exceptions1
 import Exceptions2
@@ -129,6 +130,7 @@ newtype TCPPQuery =
   TDeadCode9PackageQuery(DeadCode9Query q) or
   TDeclarationsPackageQuery(DeclarationsQuery q) or
   TDeclarations1PackageQuery(Declarations1Query q) or
+  TDeclarations2PackageQuery(Declarations2Query q) or
   TExceptionSafetyPackageQuery(ExceptionSafetyQuery q) or
   TExceptions1PackageQuery(Exceptions1Query q) or
   TExceptions2PackageQuery(Exceptions2Query q) or
@@ -225,6 +227,7 @@ predicate isQueryMetadata(Query query, string queryId, string ruleId, string cat
   isDeadCode9QueryMetadata(query, queryId, ruleId, category) or
   isDeclarationsQueryMetadata(query, queryId, ruleId, category) or
   isDeclarations1QueryMetadata(query, queryId, ruleId, category) or
+  isDeclarations2QueryMetadata(query, queryId, ruleId, category) or
   isExceptionSafetyQueryMetadata(query, queryId, ruleId, category) or
   isExceptions1QueryMetadata(query, queryId, ruleId, category) or
   isExceptions2QueryMetadata(query, queryId, ruleId, category) or

cpp/common/src/codingstandards/cpp/rules/incompatiblefunctiondeclaration/IncompatibleFunctionDeclaration.qll

@@ -0,0 +1,62 @@
+/**
+ * Provides a configurable module IncompatibleFunctionDeclaration with a `problems` predicate
+ * for the following issue:
+ * Declaring incompatible functions, in other words same named function of different
+ * return types or with different numbers of parameters or parameter types, then
+ * accessing those functions can lead to undefined behaviour.
+ */
+
+import cpp
+import codingstandards.cpp.Customizations
+import codingstandards.cpp.Exclusions
+import codingstandards.cpp.Identifiers
+import codingstandards.cpp.types.Compatible
+
+predicate interestedInFunctions(
+  FunctionDeclarationEntry f1, FunctionDeclarationEntry f2, ExternalIdentifiers d1,
+  ExternalIdentifiers d2
+) {
+  not f1 = f2 and
+  d1 = f1.getDeclaration() and
+  d2 = f2.getDeclaration() and
+  f1.getName() = f2.getName()
+}
+
+predicate interestedInFunctions(FunctionDeclarationEntry f1, FunctionDeclarationEntry f2) {
+  interestedInFunctions(f1, f2, _, _)
+}
+
+module FuncDeclEquiv =
+  FunctionDeclarationTypeEquivalence<TypesCompatibleConfig, interestedInFunctions/2>;
+
+signature module IncompatibleFunctionDeclarationConfigSig {
+  Query getQuery();
+}
+
+module IncompatibleFunctionDeclaration<IncompatibleFunctionDeclarationConfigSig Config> {
+  query predicate problems(
+    FunctionDeclarationEntry f1, string message, FunctionDeclarationEntry f2, string secondMessage
+  ) {
+    exists(ExternalIdentifiers d1, ExternalIdentifiers d2 |
+      not isExcluded(f1, Config::getQuery()) and
+      not isExcluded(f2, Config::getQuery()) and
+      interestedInFunctions(f1, f2, d1, d2) and
+      (
+        //return type check
+        not FuncDeclEquiv::equalReturnTypes(f1, f2)
+        or
+        //parameter type check
+        not FuncDeclEquiv::equalParameterTypes(f1, f2)
+      ) and
+      // Apply ordering on start line, trying to avoid the optimiser applying this join too early
+      // in the pipeline
+      exists(int f1Line, int f2Line |
+        f1.getLocation().hasLocationInfo(_, f1Line, _, _, _) and
+        f2.getLocation().hasLocationInfo(_, f2Line, _, _, _) and
+        f1Line >= f2Line
+      ) and
+      secondMessage = f2.getName() and
+      message = "The object is not compatible with a re-declaration $@."
+    )
+  }
+}

cpp/common/src/codingstandards/cpp/rules/incompatibleobjectdeclaration/IncompatibleObjectDeclaration.qll

@@ -0,0 +1,49 @@
+/**
+ * Provides a configurable module IncompatibleObjectDeclaration with a `problems` predicate
+ * for the following issue:
+ * Declaring incompatible objects, in other words same named objects of different
+ * types, then accessing those objects can lead to undefined behavior.
+ */
+
+import cpp
+import codingstandards.cpp.Customizations
+import codingstandards.cpp.Exclusions
+import codingstandards.cpp.Identifiers
+import codingstandards.cpp.types.Compatible
+
+signature module IncompatibleObjectDeclarationConfigSig {
+  Query getQuery();
+}
+
+class VariableDeclarationEntryExternal extends VariableDeclarationEntry {
+  VariableDeclarationEntryExternal() { this.getDeclaration() instanceof ExternalIdentifiers }
+}
+
+predicate relevantPair(VariableDeclarationEntryExternal varA, VariableDeclarationEntryExternal varB) {
+  not varA = varB and
+  varA.getVariable().getName() = varB.getVariable().getName()
+}
+
+predicate relevantTypes(Type a, Type b) {
+  exists(VariableDeclarationEntryExternal varA, VariableDeclarationEntryExternal varB |
+    relevantPair(varA, varB) and
+    a = varA.getType() and
+    b = varB.getType()
+  )
+}
+
+module IncompatibleObjectDeclaration<IncompatibleObjectDeclarationConfigSig Config> {
+  query predicate problems(
+    VariableDeclarationEntryExternal decl1, string message, VariableDeclarationEntryExternal decl2,
+    string secondMessage
+  ) {
+    not isExcluded(decl1, Config::getQuery()) and
+    not isExcluded(decl2, Config::getQuery()) and
+    relevantPair(decl1, decl2) and
+    not TypeEquivalence<TypesCompatibleConfig, relevantTypes/2>::equalTypes(decl1.getType(),
+      decl2.getType()) and
+    decl1.getLocation().getStartLine() >= decl2.getLocation().getStartLine() and
+    secondMessage = decl2.getName() and
+    message = "The object is not compatible with a re-declaration $@."
+  }
+}

cpp/common/src/codingstandards/cpp/types/Compatible.qll

@@ -379,6 +379,7 @@ module TypeEquivalence<TypeEquivalenceSig Config, interestedInEquality/2 interes
    * `interestedInNestedTypes` holds for the types, and holds if `t1` and `t2` are identical,
    * regardless of how `TypeEquivalenceSig` is defined.
    */
+  pragma[nomagic]
   predicate equalTypes(Type t1, Type t2) {
     interestedInNestedTypes(pragma[only_bind_into](t1), pragma[only_bind_into](t2)) and
     (

cpp/common/test/rules/incompatiblefunctiondeclaration/IncompatibleFunctionDeclaration.expected

@@ -0,0 +1,5 @@
+| test1.cpp:1:12:1:12 | declaration of f | The object is not compatible with a re-declaration $@. | test.cpp:1:6:1:6 | definition of f | f |
+| test.cpp:1:6:1:6 | definition of f | The object is not compatible with a re-declaration $@. | test1.cpp:1:12:1:12 | declaration of f | f |
+| test.cpp:5:6:5:7 | declaration of f1 | The object is not compatible with a re-declaration $@. | test1.cpp:2:13:2:14 | declaration of f1 | f1 |
+| test.cpp:6:6:6:7 | definition of f2 | The object is not compatible with a re-declaration $@. | test1.cpp:3:6:3:7 | definition of f2 | f2 |
+| test.cpp:9:17:9:18 | declaration of f4 | The object is not compatible with a re-declaration $@. | test1.cpp:6:17:6:18 | declaration of f4 | f4 |

cpp/common/test/rules/incompatiblefunctiondeclaration/IncompatibleFunctionDeclaration.ql

@@ -0,0 +1,8 @@
+// GENERATED FILE - DO NOT MODIFY
+import codingstandards.cpp.rules.incompatiblefunctiondeclaration.IncompatibleFunctionDeclaration
+
+module TestFileConfig implements IncompatibleFunctionDeclarationConfigSig {
+  Query getQuery() { result instanceof TestQuery }
+}
+
+import IncompatibleFunctionDeclaration<TestFileConfig>

cpp/common/test/rules/incompatiblefunctiondeclaration/test.cpp

@@ -0,0 +1,10 @@
+long f(int a) { // NON_COMPLIANT
+  return a * 2;
+}
+
+void f1(long a); // NON_COMPLIANT
+void f2() {}     // NON_COMPLIANT
+int f3();        // COMPLIANT
+
+extern "C" long f4(int a); // NON_COMPLIANT
+long f5();                 // NON_COMPLIANT[FALSE_NEGATIVE]