github · lcartey · Sep 30, 2022 · Aug 18, 2022 · Aug 18, 2022 · Aug 18, 2022
diff --git a/change_notes/2022-08-18-variable-templates-reused-name.md b/change_notes/2022-08-18-variable-templates-reused-name.md
@@ -0,0 +1,2 @@
+ - `A2-10-5` - `IdentifierNameOfANonMemberObjectWithExternalOrInternalLinkageIsReused.ql`
+   - Reduce false positives by excluding variable template instantiations.
diff --git a/...rc/rules/A2-10-5/IdentifierNameOfANonMemberObjectWithExternalOrInternalLinkageIsReused.ql b/...rc/rules/A2-10-5/IdentifierNameOfANonMemberObjectWithExternalOrInternalLinkageIsReused.ql
@@ -32,7 +32,11 @@ where
  not isExcluded(o2,
    NamingPackage::identifierNameOfANonMemberObjectWithExternalOrInternalLinkageIsReusedQuery()) and
  not o1 = o2 and
-  o1.getName() = o2.getName()
+  o1.getName() = o2.getName() and
+  // Only consider variables from uninstantiated templates, to avoid false positives where o1 and
+  // o2 are the same object across different template instantiations
+  not o1.isFromTemplateInstantiation(_) and
+  not o2.isFromTemplateInstantiation(_)
 select o2,
  "Identifier name of non-member object $@ reuses the identifier name of non-member object $@.", o2,
  o2.getName(), o1, o1.getName()
diff --git a/...es/A2-10-5/IdentifierNameOfANonMemberObjectWithExternalOrInternalLinkageIsReused.expected b/...es/A2-10-5/IdentifierNameOfANonMemberObjectWithExternalOrInternalLinkageIsReused.expected
@@ -1,2 +1,4 @@
 | test1a.cpp:6:12:6:13 | g3 | Identifier name of non-member object $@ reuses the identifier name of non-member object $@. | test1a.cpp:6:12:6:13 | g3 | g3 | test1b.cpp:7:12:7:13 | g3 | g3 |
+| test1a.cpp:17:43:17:43 | number_two | Identifier name of non-member object $@ reuses the identifier name of non-member object $@. | test1a.cpp:17:43:17:43 | number_two | number_two | test1b.cpp:12:43:12:43 | number_two | number_two |
 | test1b.cpp:7:12:7:13 | g3 | Identifier name of non-member object $@ reuses the identifier name of non-member object $@. | test1b.cpp:7:12:7:13 | g3 | g3 | test1a.cpp:6:12:6:13 | g3 | g3 |
+| test1b.cpp:12:43:12:43 | number_two | Identifier name of non-member object $@ reuses the identifier name of non-member object $@. | test1b.cpp:12:43:12:43 | number_two | number_two | test1a.cpp:17:43:17:43 | number_two | number_two |
diff --git a/cpp/autosar/test/rules/A2-10-5/test1a.cpp b/cpp/autosar/test/rules/A2-10-5/test1a.cpp
@@ -5,3 +5,17 @@ static int g1 = 0;
 static int g2;      // COMPLIANT
 static int g3 = 1;  // NON_COMPLIANT
 static void f1(){}; // NON_COMPLIANT
+
+// Variable template has multiple declarations: one for the uninstantiated
+// template and one for each instantiation
+template <class T> constexpr T number_one = T(1); // COMPLIANT
+
+int test() { return number_one<int>; }
+
+long test2() { return number_one<long>; }
+
+template <class T> constexpr T number_two = T(1); // NON_COMPLIANT
+
+int test3() { return number_two<int>; }
+
+long test4() { return number_two<long>; }
diff --git a/cpp/autosar/test/rules/A2-10-5/test1b.cpp b/cpp/autosar/test/rules/A2-10-5/test1b.cpp
@@ -8,3 +8,9 @@ static int g3 = 0; // NON_COMPLIANT
 }

 static void f1() {} // NON_COMPLIANT
+
+template <class T> constexpr T number_two = T(1); // NON_COMPLIANT
+
+int test3() { return number_two<int>; }
+
+long test4() { return number_two<long>; }
Original file line number	Diff line number	Diff line change
		@@ -0,0 +1,2 @@
		- `A2-10-5` - `IdentifierNameOfANonMemberObjectWithExternalOrInternalLinkageIsReused.ql`
		- Reduce false positives by excluding variable template instantiations.