Implement Misra-c Noreturn rule package.

Covers rules 17-9 through 17-11, regarding the use of the _Noreturn attribute.

Author: MichaelRFairhurst

c/misra/src/rules/RULE-17-10/NonVoidReturnTypeOfNoreturnFunction.ql

@@ -0,0 +1,23 @@
+/**
+ * @id c/misra/non-void-return-type-of-noreturn-function
+ * @name RULE-17-10: A function declared with _noreturn shall have a return type of void
+ * @description Function declared with _noreturn will by definition not return a value, and should
+ *              be declared to return void.
+ * @kind problem
+ * @precision very-high
+ * @problem.severity recommendation
+ * @tags external/misra/id/rule-17-10
+ *       external/misra/obligation/required
+ */
+
+import cpp
+import codingstandards.c.misra
+
+from Function f, Type returnType
+where
+  not isExcluded(f, NoReturnPackage::nonVoidReturnTypeOfNoreturnFunctionQuery()) and
+  f.getASpecifier().getName() = "noreturn" and
+  returnType = f.getType() and
+  not returnType instanceof VoidType
+select
+  f, "The function " + f.getName() + " is declared _noreturn but has a return type of " + returnType.toString() + "."

c/misra/src/rules/RULE-17-11/FunctionWithNoReturningBranchShouldBeNoreturn.ql

@@ -0,0 +1,24 @@
+/**
+ * @id c/misra/function-with-no-returning-branch-should-be-noreturn
+ * @name RULE-17-11: A function without a branch that returns shall be declared with _Noreturn
+ * @description Functions which cannot return should be declared with _Noreturn.
+ * @kind problem
+ * @precision high
+ * @problem.severity recommendation
+ * @tags external/misra/id/rule-17-11
+ *       external/misra/obligation/advisory
+ */
+
+import cpp
+import codingstandards.c.misra
+
+from Function f
+where
+  not isExcluded(f, NoReturnPackage::returnStatementInNoreturnFunctionQuery()) and
+  not f.getASpecifier().getName() = "noreturn" and
+  not exists(ReturnStmt s |
+    f = s.getEnclosingFunction() and
+    s.getBasicBlock().isReachable()
+  )
+select
+  f, "The function " + f.getName() + " cannot return and should be declared attribute _Noreturn."

c/misra/src/rules/RULE-17-9/ReturnStatementInNoreturnFunction.ql

@@ -0,0 +1,24 @@
+/**
+ * @id c/misra/return-statement-in-noreturn-function
+ * @name RULE-17-9: Verify that a function declared with _Noreturn does not return
+ * @description Returning inside a function declared with _Noreturn is undefined behavior.
+ * @kind problem
+ * @precision very-high
+ * @problem.severity error
+ * @tags external/misra/id/rule-17-9
+ *       external/misra/obligation/mandatory
+ */
+
+import cpp
+import codingstandards.c.misra
+
+from Function f
+where
+  not isExcluded(f, NoReturnPackage::returnStatementInNoreturnFunctionQuery()) and
+  f.getASpecifier().getName() = "noreturn" and
+  exists(ReturnStmt s |
+    f = s.getEnclosingFunction() and
+    s.getBasicBlock().isReachable()
+  )
+select
+  f, "The function " + f.getName() + " declared with attribute _Noreturn returns a value."

c/misra/test/rules/RULE-17-10/NonVoidReturnTypeOfNoreturnFunction.expected

@@ -0,0 +1 @@
+No expected results have yet been specified

c/misra/test/rules/RULE-17-10/NonVoidReturnTypeOfNoreturnFunction.qlref

@@ -0,0 +1 @@
+rules/RULE-17-10/NonVoidReturnTypeOfNoreturnFunction.ql

c/misra/test/rules/RULE-17-10/test.c

@@ -0,0 +1,24 @@
+#include "stdlib.h"
+
+void f1(); // COMPLIANT
+int f2(); // COMPLIANT
+_Noreturn void f3(); // COMPLIANT
+_Noreturn int f4(); // NON-COMPLIANT
+
+void f5() { // COMPLIANT
+}
+
+int f6() { // COMPLIANT
+  return 0;
+}
+
+_Noreturn void f7() { // COMPLIANT
+  abort();
+}
+
+_Noreturn int f8() { // NON-COMPLIANT
+  abort();
+  return 0;
+}
+
+_Noreturn void* f9(); // NON-COMPLIANT

c/misra/test/rules/RULE-17-11/FunctionWithNoReturningBranchShouldBeNoreturn.expected

@@ -0,0 +1,4 @@
+| test.c:7:6:7:21 | test_noreturn_f2 | The function test_noreturn_f2 cannot return and should be declared attribute _Noreturn. |
+| test.c:19:6:19:21 | test_noreturn_f4 | The function test_noreturn_f4 cannot return and should be declared attribute _Noreturn. |
+| test.c:48:6:48:21 | test_noreturn_f8 | The function test_noreturn_f8 cannot return and should be declared attribute _Noreturn. |
+| test.c:64:6:64:22 | test_noreturn_f10 | The function test_noreturn_f10 cannot return and should be declared attribute _Noreturn. |

c/misra/test/rules/RULE-17-11/FunctionWithNoReturningBranchShouldBeNoreturn.qlref

@@ -0,0 +1 @@
+rules/RULE-17-11/FunctionWithNoReturningBranchShouldBeNoreturn.ql

c/misra/test/rules/RULE-17-11/test.c

@@ -0,0 +1,80 @@
+#include "stdlib.h"
+
+_Noreturn void test_noreturn_f1(int i) { // COMPLIANT
+  abort();
+}
+
+void test_noreturn_f2(int i) { // NON_COMPLIANT
+  abort();
+}
+
+
+_Noreturn void test_noreturn_f3(int i) { // COMPLIANT
+  if (i > 0) {
+    abort();
+  }
+  exit(1);
+}
+
+void test_noreturn_f4(int i) { // NON_COMPLIANT
+  if (i > 0) {
+    abort();
+  }
+  exit(1);
+}
+
+void test_noreturn_f5(int i) { // COMPLIANT
+  if (i > 0) {
+    return;
+  }
+  exit(1);
+}
+
+void test_noreturn_f6(int i) { // COMPLIANT
+  if (i > 0) {
+    abort();
+  }
+  if (i < 0) {
+    abort();
+  }
+}
+
+void test_noreturn_f7(int i) { // COMPLIANT
+  if (i > 0) {
+    abort();
+  }
+}
+
+void test_noreturn_f8(int i) { // NON_COMPLIANT
+  if (i > 0) {
+    abort();
+  } else {
+    abort();
+  }
+}
+
+_Noreturn void test_noreturn_f9(int i) { // COMPLIANT
+  if (i > 0) {
+    abort();
+  } else {
+    abort();
+  }
+}
+
+void test_noreturn_f10(int i) { // NON_COMPLIANT
+  if (i > 0) {
+    abort();
+  }
+  while (1) {
+    i = 5;
+  }
+}
+
+_Noreturn void test_noreturn_f11(int i) { // COMPLIANT
+  if (i > 0) {
+    abort();
+  }
+  while (1) {
+    i = 5;
+  }
+}

c/misra/test/rules/RULE-17-9/ReturnStatementInNoreturnFunction.expected

@@ -0,0 +1,2 @@
+| test.c:7:16:7:31 | test_noreturn_f2 | The function test_noreturn_f2 declared with attribute _Noreturn returns a value. |
+| test.c:32:16:32:31 | test_noreturn_f5 | The function test_noreturn_f5 declared with attribute _Noreturn returns a value. |