Declarations5: add RULE-5-2

Author: knewbury01

c/misra/src/rules/RULE-5-2/IdentifiersDeclaredInTheSameScopeNotDistinct.ql

@@ -0,0 +1,38 @@
+/**
+ * @id c/misra/identifiers-declared-in-the-same-scope-not-distinct
+ * @name RULE-5-2: Identifiers declared in the same scope and name space shall be distinct
+ * @description Using nondistinct identifiers results in undefined behaviour.
+ * @kind problem
+ * @precision very-high
+ * @problem.severity warning
+ * @tags external/misra/id/rule-5-2
+ *       correctness
+ *       maintainability
+ *       readability
+ *       external/misra/obligation/required
+ */
+
+import cpp
+import codingstandards.c.misra
+import codingstandards.cpp.Identifiers
+
+from InterestingIdentifiers d, InterestingIdentifiers d2
+where
+  not isExcluded(d, Declarations5Package::identifiersDeclaredInTheSameScopeNotDistinctQuery()) and
+  not isExcluded(d2, Declarations5Package::identifiersDeclaredInTheSameScopeNotDistinctQuery()) and
+  //this rule does not apply if both are external identifiers
+  //that is covered by RULE-5-3
+  not (
+    d instanceof ExternalIdentifiers and
+    d2 instanceof ExternalIdentifiers
+  ) and
+  d.getNamespace() = d2.getNamespace() and
+  d.getParentScope() = d2.getParentScope() and
+  not d = d2 and
+  d.getLocation().getStartLine() >= d2.getLocation().getStartLine() and
+  //first 63 chars in the name as per C99
+  d.getSignificantNameComparedToMacro() = d2.getSignificantNameComparedToMacro() and
+  not d.getName() = d2.getName()
+select d,
+  "Identifer " + d.getName() + " is nondistinct in characters at or over 63 limit, compared to $@",
+  d2, d2.getName()

c/misra/test/rules/RULE-5-2/IdentifiersDeclaredInTheSameScopeNotDistinct.expected

@@ -0,0 +1 @@
+| test.c:8:5:8:68 | iltiqzxgfqsgigwfuyntzghvzltueatcxqnqofnnvjyszmcsylyohvqaosjbqyyB | Identifer iltiqzxgfqsgigwfuyntzghvzltueatcxqnqofnnvjyszmcsylyohvqaosjbqyyB is nondistinct in characters at or over 63 limit, compared to $@ | test.c:2:5:2:68 | iltiqzxgfqsgigwfuyntzghvzltueatcxqnqofnnvjyszmcsylyohvqaosjbqyyA | iltiqzxgfqsgigwfuyntzghvzltueatcxqnqofnnvjyszmcsylyohvqaosjbqyyA |

c/misra/test/rules/RULE-5-2/IdentifiersDeclaredInTheSameScopeNotDistinct.qlref

@@ -0,0 +1 @@
+rules/RULE-5-2/IdentifiersDeclaredInTheSameScopeNotDistinct.ql

c/misra/test/rules/RULE-5-2/test.c

@@ -0,0 +1,26 @@
+extern int
+    iltiqzxgfqsgigwfuyntzghvzltueatcxqnqofnnvjyszmcsylyohvqaosjbqyyA; // NON_COMPLIANT
+                                                                      // -
+                                                                      // length
+                                                                      // 64
+
+static int
+    iltiqzxgfqsgigwfuyntzghvzltueatcxqnqofnnvjyszmcsylyohvqaosjbqyyB; // NON_COMPLIANT
+                                                                      // -
+                                                                      // length
+                                                                      // 64
+
+void f() {
+  int iltiqzxgfqsgigwfuyntzghvzltueatcxqnqofnnvjyszmcsylyohvqaosjbqyyC; // COMPLIANT
+                                                                        // -
+                                                                        // length
+                                                                        // 64
+                                                                        // but
+                                                                        // diff
+                                                                        // scope
+}
+
+static int
+    iltiqzxgfqsgigwfuyntzghvzltueatcxqnqofnnvjy_C; // COMPLIANT length <63
+static int
+    iltiqzxgfqsgigwfuyntzghvzltueatcxqnqofnnvjy_D; // COMPLIANT length <63

cpp/common/src/codingstandards/cpp/exclusions/c/Declarations5.qll

@@ -3,9 +3,19 @@ import cpp
 import RuleMetadata
 import codingstandards.cpp.exclusions.RuleMetadata
 
-newtype Declarations5Query = TExternalObjectOrFunctionNotDeclaredInOneFileQuery()
+newtype Declarations5Query =
+  TIdentifiersDeclaredInTheSameScopeNotDistinctQuery() or
+  TExternalObjectOrFunctionNotDeclaredInOneFileQuery()
 
 predicate isDeclarations5QueryMetadata(Query query, string queryId, string ruleId) {
+  query =
+    // `Query` instance for the `identifiersDeclaredInTheSameScopeNotDistinct` query
+    Declarations5Package::identifiersDeclaredInTheSameScopeNotDistinctQuery() and
+  queryId =
+    // `@id` for the `identifiersDeclaredInTheSameScopeNotDistinct` query
+    "c/misra/identifiers-declared-in-the-same-scope-not-distinct" and
+  ruleId = "RULE-5-2"
+  or
   query =
     // `Query` instance for the `externalObjectOrFunctionNotDeclaredInOneFile` query
     Declarations5Package::externalObjectOrFunctionNotDeclaredInOneFileQuery() and
@@ -16,6 +26,13 @@ predicate isDeclarations5QueryMetadata(Query query, string queryId, string ruleI
 }
 
 module Declarations5Package {
+  Query identifiersDeclaredInTheSameScopeNotDistinctQuery() {
+    //autogenerate `Query` type
+    result =
+      // `Query` type for `identifiersDeclaredInTheSameScopeNotDistinct` query
+      TQueryC(TDeclarations5PackageQuery(TIdentifiersDeclaredInTheSameScopeNotDistinctQuery()))
+  }
+
   Query externalObjectOrFunctionNotDeclaredInOneFileQuery() {
     //autogenerate `Query` type
     result =

rule_packages/c/Declarations5.json

@@ -1,5 +1,30 @@
 {
   "MISRA-C-2012": {
+    "RULE-5-2": {
+      "properties": {
+        "obligation": "required"
+      },
+      "queries": [
+        {
+          "description": "Using nondistinct identifiers results in undefined behaviour.",
+          "kind": "problem",
+          "name": "Identifiers declared in the same scope and name space shall be distinct",
+          "precision": "very-high",
+          "severity": "warning",
+          "short_name": "IdentifiersDeclaredInTheSameScopeNotDistinct",
+          "tags": [
+            "correctness",
+            "maintainability",
+            "readability"
+          ],
+          "implementation_scope": {
+            "description": "This query considers the first 63 characters of identifiers as significant, as per C99 for nonexternal identifiers and reports the case when names are longer than 63 characters and differ in those characters past the 63 first only. This query does not consider universal or extended source characters.",
+            "items": []
+          }
+        }
+      ],
+      "title": "Identifiers declared in the same scope and name space shall be distinct"
+    },
     "RULE-8-5": {
       "properties": {
         "obligation": "required"

rules.csv

@@ -632,7 +632,7 @@ c,MISRA-C-2012,RULE-3-2,Yes,Required,,,Line-splicing shall not be used in // com
 c,MISRA-C-2012,RULE-4-1,Yes,Required,,,Octal and hexadecimal escape sequences shall be terminated,A2-13-1 M2-13-2,Syntax,Medium,
 c,MISRA-C-2012,RULE-4-2,No,Advisory,,,Trigraphs should not be used,A2-5-1,,Import,
 c,MISRA-C-2012,RULE-5-1,Yes,Required,,,External identifiers shall be distinct,,Declarations1,Medium,
-c,MISRA-C-2012,RULE-5-2,Yes,Required,,,Identifiers declared in the same scope and name space shall be distinct,,Declarations,Medium,
+c,MISRA-C-2012,RULE-5-2,Yes,Required,,,Identifiers declared in the same scope and name space shall be distinct,,Declarations5,Medium,
 c,MISRA-C-2012,RULE-5-3,Yes,Required,,,An identifier declared in an inner scope shall not hide an identifier declared in an outer scope,A2-10-1,Declarations3,Import,
 c,MISRA-C-2012,RULE-5-4,Yes,Required,,,Macro identifiers shall be distinct,,Declarations1,Easy,
 c,MISRA-C-2012,RULE-5-5,Yes,Required,,,Identifiers shall be distinct from macro names,,Declarations3,Easy,