[clang-tidy] Update cert-err58-cpp to match its new generalised form.

[malcolm.parsons]

Summary

Aaron modified cert-err58-cpp to include all exceptions thrown before main()
Update the check to match.

[aaron.ballman]

Thank you for working on this! I have a few more test cases to try, but I think you're already handling them properly.

test/clang-tidy/cert-static-object-exception.cpp

29

We should also have a test for implicitly-provided constructors, since those are noexcept if the data members all have noexcept constructors. Something like:

struct Y {
  S s;
};

Y y; // Diagnose

struct Z {
  T t;
};

Z z; // Do not diagnose

78

Let's also make sure that we're properly catching conversion operators with a test like:

struct UserConv_Bad {
  operator int() noexcept(false);
};

struct UserConv_Good {
  operator int() noexcept;
};

UserConv_Bad some_bad_func();
UserConv_Good some_good_func();

int l = some_bad_func(); // Diagnose
int m = some_good_func(); // Do not diagnose

[malcolm.parsons]

Add more tests.

[aaron.ballman]

LGTM, thank you!

[malcolm.parsons]

Add tests for operator new with FIXME comment.

[malcolm.parsons]

Check calls to operator new.

clang-tidy/cert/StaticObjectExceptionCheck.cpp

 namespace clang {
 namespace tidy {
 namespace cert {
 
 void StaticObjectExceptionCheck::registerMatchers(MatchFinder *Finder) {
   if (!getLangOpts().CPlusPlus)
     return;
 
-  // Match any static or thread_local variable declaration that is initialized
-  // with a constructor that can throw.
+  // Match any static or thread_local variable declaration that has an
+  // initializer that can throw.
   Finder->addMatcher(
       varDecl(anyOf(hasThreadStorageDuration(), hasStaticStorageDuration()),
               unless(hasAncestor(functionDecl())),
-              hasInitializer(ignoringImplicit(cxxConstructExpr(hasDeclaration(
-                  cxxConstructorDecl(unless(isNoThrow())).bind("ctor"))))))
+              anyOf(hasDescendant(cxxConstructExpr(hasDeclaration(
+                        cxxConstructorDecl(unless(isNoThrow())).bind("func")))),
+                    hasDescendant(cxxNewExpr(hasDeclaration(
+                        functionDecl(unless(isNoThrow())).bind("func")))),
+                    hasDescendant(callExpr(hasDeclaration(
+                        functionDecl(unless(isNoThrow())).bind("func"))))))
           .bind("var"),
       this);
 }
 
 void StaticObjectExceptionCheck::check(const MatchFinder::MatchResult &Result) {
   const auto *VD = Result.Nodes.getNodeAs<VarDecl>("var");
-  const auto *Ctor = Result.Nodes.getNodeAs<CXXConstructorDecl>("ctor");
+  const auto *Func = Result.Nodes.getNodeAs<FunctionDecl>("func");
 
   diag(VD->getLocation(),
-       "construction of %0 with %select{static|thread_local}1 storage "
+       "initialization of %0 with %select{static|thread_local}1 storage "
        "duration may throw an exception that cannot be caught")
       << VD << (VD->getStorageDuration() == SD_Static ? 0 : 1);
-  diag(Ctor->getLocation(), "possibly throwing constructor declared here",
-       DiagnosticIDs::Note);
+
+  SourceLocation FuncLocation = Func->getLocation();
+  if(FuncLocation.isValid()) {
+    diag(FuncLocation,
+         "possibly throwing %select{constructor|function}0 declared here",
+         DiagnosticIDs::Note)
+        << (isa<CXXConstructorDecl>(Func) ? 0 : 1);
+  }
 }
 
 } // namespace cert
 } // namespace tidy
 } // namespace clang

docs/clang-tidy/checks/cert-err58-cpp.rst

 .. title:: clang-tidy - cert-err58-cpp
 
 cert-err58-cpp
 ==============
 
 This check flags all ``static`` or ``thread_local`` variable declarations where
-the constructor for the object may throw an exception.
+the initializer for the object may throw an exception.
 
 This check corresponds to the CERT C++ Coding Standard rule
-`ERR58-CPP. Constructors of objects with static or thread storage duration must not throw exceptions
-<https://www.securecoding.cert.org/confluence/display/cplusplus/ERR58-CPP.+Constructors+of+objects+with+static+or+thread+storage+duration+must+not+throw+exceptions>`_.
+`ERR58-CPP. Handle all exceptions thrown before main() begins executing
+<https://www.securecoding.cert.org/confluence/display/cplusplus/ERR58-CPP.+Handle+all+exceptions+thrown+before+main%28%29+begins+executing>`_.

test/clang-tidy/cert-static-object-exception.cpp

 struct U {
   U() {}
 };
 
 struct V {
   explicit V(const char *) {} // Can throw
 };
 
-struct Cleanup
-{
+struct Cleanup {
   ~Cleanup() {}
 };
 
 struct W {
   W(Cleanup c = {}) noexcept(false);
 };
 
+struct X {
+  X(S = {}) noexcept;
+};
+
+struct Y {
+  S s;
+};
+
+struct Z {
+  T t;
+};
+
+int f();
+int g() noexcept(false);
+int h() noexcept(true);
+
+struct UserConv_Bad {
+  operator int() noexcept(false);
+};
+
+struct UserConv_Good {
+  operator int() noexcept;
+};
+
+UserConv_Bad some_bad_func() noexcept;
+UserConv_Good some_good_func() noexcept;
 
 S s;
-// CHECK-MESSAGES: :[[@LINE-1]]:3: warning: construction of 's' with static storage duration may throw an exception that cannot be caught [cert-err58-cpp]
+// CHECK-MESSAGES: :[[@LINE-1]]:3: warning: initialization of 's' with static storage duration may throw an exception that cannot be caught [cert-err58-cpp]
 // CHECK-MESSAGES: 4:3: note: possibly throwing constructor declared here
 T t; // ok
 U u;
-// CHECK-MESSAGES: :[[@LINE-1]]:3: warning: construction of 'u' with static storage duration may throw an exception that cannot be caught
+// CHECK-MESSAGES: :[[@LINE-1]]:3: warning: initialization of 'u' with static storage duration may throw an exception that cannot be caught
 // CHECK-MESSAGES: 12:3: note: possibly throwing constructor declared here
 V v("v");
-// CHECK-MESSAGES: :[[@LINE-1]]:3: warning: construction of 'v' with static storage duration may throw an exception that cannot be caught
+// CHECK-MESSAGES: :[[@LINE-1]]:3: warning: initialization of 'v' with static storage duration may throw an exception that cannot be caught
 // CHECK-MESSAGES: 16:12: note: possibly throwing constructor declared here
 W w;
-// CHECK-MESSAGES: :[[@LINE-1]]:3: warning: construction of 'w' with static storage duration may throw an exception that cannot be caught
-// CHECK-MESSAGES: 25:3: note: possibly throwing constructor declared here
+// CHECK-MESSAGES: :[[@LINE-1]]:3: warning: initialization of 'w' with static storage duration may throw an exception that cannot be caught
+// CHECK-MESSAGES: 24:3: note: possibly throwing constructor declared here
+X x1(S{});
+// CHECK-MESSAGES: :[[@LINE-1]]:3: warning: initialization of 'x1' with static storage duration may throw an exception that cannot be caught
+// CHECK-MESSAGES: 4:3: note: possibly throwing constructor declared here
+X x2;
+// CHECK-MESSAGES: :[[@LINE-1]]:3: warning: initialization of 'x2' with static storage duration may throw an exception that cannot be caught
+// CHECK-MESSAGES: 4:3: note: possibly throwing constructor declared here
+Y y;
+// CHECK-MESSAGES: :[[@LINE-1]]:3: warning: initialization of 'y' with static storage duration may throw an exception that cannot be caught
+// CHECK-MESSAGES: 31:8: note: possibly throwing constructor declared here
+Z z;
+
+int i = f();
+// CHECK-MESSAGES: :[[@LINE-1]]:5: warning: initialization of 'i' with static storage duration may throw an exception that cannot be caught
+// CHECK-MESSAGES: 39:5: note: possibly throwing function declared here
+int j = g();
+// CHECK-MESSAGES: :[[@LINE-1]]:5: warning: initialization of 'j' with static storage duration may throw an exception that cannot be caught
+// CHECK-MESSAGES: 40:5: note: possibly throwing function declared here
+int k = h();
+int l = some_bad_func();
+// CHECK-MESSAGES: :[[@LINE-1]]:5: warning: initialization of 'l' with static storage duration may throw an exception that cannot be caught
+// CHECK-MESSAGES: 44:3: note: possibly throwing function declared here
+int m = some_good_func();
+
+typedef decltype(sizeof(int)) size_t;
+inline void *operator new(size_t sz, void *here) noexcept { return here; }
+char n[sizeof(int)];
+int *o = new (n) int();
+int *p = new int();
+// CHECK-MESSAGES: :[[@LINE-1]]:6: warning: initialization of 'p' with static storage duration may throw an exception that cannot be caught
+
 
 thread_local S s3;
-// CHECK-MESSAGES: :[[@LINE-1]]:16: warning: construction of 's3' with thread_local storage duration may throw an exception that cannot be caught
+// CHECK-MESSAGES: :[[@LINE-1]]:16: warning: initialization of 's3' with thread_local storage duration may throw an exception that cannot be caught
 thread_local T t3; // ok
 thread_local U u3;
-// CHECK-MESSAGES: :[[@LINE-1]]:16: warning: construction of 'u3' with thread_local storage duration may throw an exception that cannot be caught
+// CHECK-MESSAGES: :[[@LINE-1]]:16: warning: initialization of 'u3' with thread_local storage duration may throw an exception that cannot be caught
 thread_local V v3("v");
-// CHECK-MESSAGES: :[[@LINE-1]]:16: warning: construction of 'v3' with thread_local storage duration may throw an exception that cannot be caught
+// CHECK-MESSAGES: :[[@LINE-1]]:16: warning: initialization of 'v3' with thread_local storage duration may throw an exception that cannot be caught
 thread_local W w3;
-// CHECK-MESSAGES: :[[@LINE-1]]:16: warning: construction of 'w3' with thread_local storage duration may throw an exception that cannot be caught
+// CHECK-MESSAGES: :[[@LINE-1]]:16: warning: initialization of 'w3' with thread_local storage duration may throw an exception that cannot be caught
 
 void f(S s1, T t1, U u1, V v1, W w1) { // ok, ok, ok, ok, ok
   S s2; // ok
   T t2; // ok
   U u2; // ok
   V v2("v"); // ok
   W w2; // ok
 
   thread_local S s3; // ok
   thread_local T t3; // ok
   thread_local U u3; // ok
   thread_local V v3("v"); // ok
   thread_local W w3; // ok
 
   static S s4; // ok
   static T t4; // ok
   static U u4; // ok
   static V v4("v"); // ok
   static W w4; // ok
 }
 
 namespace {
 S s;
-// CHECK-MESSAGES: :[[@LINE-1]]:3: warning: construction of 's' with static storage duration may throw an exception that cannot be caught [cert-err58-cpp]
+// CHECK-MESSAGES: :[[@LINE-1]]:3: warning: initialization of 's' with static storage duration may throw an exception that cannot be caught [cert-err58-cpp]
 // CHECK-MESSAGES: 4:3: note: possibly throwing constructor declared here
 T t; // ok
 U u;
-// CHECK-MESSAGES: :[[@LINE-1]]:3: warning: construction of 'u' with static storage duration may throw an exception that cannot be caught
+// CHECK-MESSAGES: :[[@LINE-1]]:3: warning: initialization of 'u' with static storage duration may throw an exception that cannot be caught
 // CHECK-MESSAGES: 12:3: note: possibly throwing constructor declared here
 V v("v");
-// CHECK-MESSAGES: :[[@LINE-1]]:3: warning: construction of 'v' with static storage duration may throw an exception that cannot be caught
+// CHECK-MESSAGES: :[[@LINE-1]]:3: warning: initialization of 'v' with static storage duration may throw an exception that cannot be caught
 // CHECK-MESSAGES: 16:12: note: possibly throwing constructor declared here
 W w;
-// CHECK-MESSAGES: :[[@LINE-1]]:3: warning: construction of 'w' with static storage duration may throw an exception that cannot be caught
-// CHECK-MESSAGES: 25:3: note: possibly throwing constructor declared here
+// CHECK-MESSAGES: :[[@LINE-1]]:3: warning: initialization of 'w' with static storage duration may throw an exception that cannot be caught
+// CHECK-MESSAGES: 24:3: note: possibly throwing constructor declared here
 
 thread_local S s3;
-// CHECK-MESSAGES: :[[@LINE-1]]:16: warning: construction of 's3' with thread_local storage duration may throw an exception that cannot be caught
+// CHECK-MESSAGES: :[[@LINE-1]]:16: warning: initialization of 's3' with thread_local storage duration may throw an exception that cannot be caught
 thread_local T t3; // ok
 thread_local U u3;
-// CHECK-MESSAGES: :[[@LINE-1]]:16: warning: construction of 'u3' with thread_local storage duration may throw an exception that cannot be caught
+// CHECK-MESSAGES: :[[@LINE-1]]:16: warning: initialization of 'u3' with thread_local storage duration may throw an exception that cannot be caught
 thread_local V v3("v");
-// CHECK-MESSAGES: :[[@LINE-1]]:16: warning: construction of 'v3' with thread_local storage duration may throw an exception that cannot be caught
+// CHECK-MESSAGES: :[[@LINE-1]]:16: warning: initialization of 'v3' with thread_local storage duration may throw an exception that cannot be caught
 thread_local W w3;
-// CHECK-MESSAGES: :[[@LINE-1]]:16: warning: construction of 'w3' with thread_local storage duration may throw an exception that cannot be caught
+// CHECK-MESSAGES: :[[@LINE-1]]:16: warning: initialization of 'w3' with thread_local storage duration may throw an exception that cannot be caught
 };
 
 class Statics {
-  static S s;
-  // CHECK-MESSAGES: :[[@LINE-1]]:12: warning: construction of 's' with static storage duration may throw an exception that cannot be caught [cert-err58-cpp]
-  // CHECK-MESSAGES: 4:3: note: possibly throwing constructor declared here
+  static S s; // warn when initialized
   static T t; // ok
-  static U u;
-  // CHECK-MESSAGES: :[[@LINE-1]]:12: warning: construction of 'u' with static storage duration may throw an exception that cannot be caught
-  // CHECK-MESSAGES: 12:3: note: possibly throwing constructor declared here
-  static V v;
-  // CHECK-MESSAGES: :[[@LINE-1]]:12: warning: construction of 'v' with static storage duration may throw an exception that cannot be caught
-  // CHECK-MESSAGES: 16:12: note: possibly throwing constructor declared here
-  static W w;
-  // CHECK-MESSAGES: :[[@LINE-1]]:12: warning: construction of 'w' with static storage duration may throw an exception that cannot be caught
-  // CHECK-MESSAGES: 25:3: note: possibly throwing constructor declared here
+  static U u; // warn when initialized
+  static V v; // warn when initialized
+  static W w; // warn when initialized
 
   void f(S s, T t, U u, V v) {
     S s2;      // ok
     T t2;      // ok
     U u2;      // ok
     V v2("v"); // ok
     W w2;      // ok
 
     thread_local S s3;      // ok
     thread_local T t3;      // ok
     thread_local U u3;      // ok
     thread_local V v3("v"); // ok
     thread_local W w3;      // ok
 
     static S s4;      // ok
     static T t4;      // ok
     static U u4;      // ok
     static V v4("v"); // ok
     static W w4;      // ok
   }
 };
 
 S Statics::s;
-// CHECK-MESSAGES: :[[@LINE-1]]:12: warning: construction of 's' with static storage duration may throw an exception that cannot be caught [cert-err58-cpp]
+// CHECK-MESSAGES: :[[@LINE-1]]:12: warning: initialization of 's' with static storage duration may throw an exception that cannot be caught [cert-err58-cpp]
 // CHECK-MESSAGES: 4:3: note: possibly throwing constructor declared here
 T Statics::t;
 U Statics::u;
-// CHECK-MESSAGES: :[[@LINE-1]]:12: warning: construction of 'u' with static storage duration may throw an exception that cannot be caught
+// CHECK-MESSAGES: :[[@LINE-1]]:12: warning: initialization of 'u' with static storage duration may throw an exception that cannot be caught
 // CHECK-MESSAGES: 12:3: note: possibly throwing constructor declared here
 V Statics::v("v");
-// CHECK-MESSAGES: :[[@LINE-1]]:12: warning: construction of 'v' with static storage duration may throw an exception that cannot be caught
+// CHECK-MESSAGES: :[[@LINE-1]]:12: warning: initialization of 'v' with static storage duration may throw an exception that cannot be caught
 // CHECK-MESSAGES: 16:12: note: possibly throwing constructor declared here
 W Statics::w;
-// CHECK-MESSAGES: :[[@LINE-1]]:12: warning: construction of 'w' with static storage duration may throw an exception that cannot be caught
-// CHECK-MESSAGES: 25:3: note: possibly throwing constructor declared here
+// CHECK-MESSAGES: :[[@LINE-1]]:12: warning: initialization of 'w' with static storage duration may throw an exception that cannot be caught
+// CHECK-MESSAGES: 24:3: note: possibly throwing constructor declared here