Merge pull request github#8428 from jketema/noreturn

C++: Handle C11 _Noreturn in DefaultOptions

Author: jketema

cpp/ql/lib/DefaultOptions.qll

@@ -54,11 +54,13 @@ class Options extends string {
    *
    * By default, this holds for `exit`, `_exit`, `abort`, `__assert_fail`,
    * `longjmp`, `__builtin_unreachable` and any function with a
-   * `noreturn` attribute.
+   * `noreturn` attribute or specifier.
    */
   predicate exits(Function f) {
     f.getAnAttribute().hasName("noreturn")
     or
+    f.getASpecifier().hasName("noreturn")
+    or
     f.hasGlobalOrStdName([
         "exit", "_exit", "abort", "__assert_fail", "longjmp", "__builtin_unreachable"
       ])

cpp/ql/lib/Options.qll

@@ -39,7 +39,7 @@ class CustomOptions extends Options {
    *
    * By default, this holds for `exit`, `_exit`, `abort`, `__assert_fail`,
    * `longjmp`, `error`, `__builtin_unreachable` and any function with a
-   * `noreturn` attribute.
+   * `noreturn` attribute or specifier.
    */
   override predicate exits(Function f) { Options.super.exits(f) }
 

cpp/ql/lib/change-notes/2022-03-14-c11-noreturn.md

@@ -0,0 +1,4 @@
+---
+category: minorAnalysis
+---
+* `DefaultOptions::exits` now holds for C11 functions with the `_Noreturn` or `noreturn` specifier.

cpp/ql/lib/semmle/code/cpp/Specifier.qll

@@ -38,7 +38,7 @@ class FunctionSpecifier extends Specifier {
 
 /**
  * A C/C++ storage class specifier: `auto`, `register`, `static`, `extern`,
- * or `mutable".
+ * or `mutable`.
  */
 class StorageClassSpecifier extends Specifier {
   StorageClassSpecifier() { this.hasName(["auto", "register", "static", "extern", "mutable"]) }

cpp/ql/test/query-tests/jsf/4.13 Functions/AV Rule 114/test.c

@@ -1,4 +1,4 @@
-
+// semmle-extractor-options: -std=c11
 int f1(void) {
     int x = 1;
     return 2;
@@ -99,3 +99,9 @@ int f14()
 {
 	__asm__("rdtsc"); // GOOD
 }
+
+_Noreturn void f15();
+
+int f16() {
+    f15(); // GOOD
+}

cpp/ql/test/query-tests/jsf/4.13 Functions/AV Rule 114/test.cpp

@@ -1,4 +1,4 @@
-
+// semmle-extractor-options: -std=c++11
 class MyValue {
 public:
 	MyValue(int _val) : val(_val) {};
@@ -164,3 +164,9 @@ int g19(int x)
 
 	return x; // GOOD
 }
+
+[[noreturn]] void g20();
+
+int g21() {
+    g20(); // GOOD
+}