[clang-tidy] Use ignoreImplicit in cert-err58-cpp check

[malcolm.parsons]

Summary

Fix a false negative in cert-err58-cpp check when calling a constructor
creates objects that require cleanup.

[aaron.ballman]

In what is surely a record response time for code reviews on a weekend, this LGTM. :-D

clang-tidy/cert/StaticObjectExceptionCheck.cpp

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.
   Finder->addMatcher(
       varDecl(anyOf(hasThreadStorageDuration(), hasStaticStorageDuration()),
               unless(hasAncestor(functionDecl())),
-              hasInitializer(cxxConstructExpr(hasDeclaration(
-                  cxxConstructorDecl(unless(isNoThrow())).bind("ctor")))))
+              hasInitializer(ignoringImplicit(cxxConstructExpr(hasDeclaration(
+                  cxxConstructorDecl(unless(isNoThrow())).bind("ctor"))))))
           .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");
 

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

 struct U {
   U() {}
 };
 
 struct V {
   explicit V(const char *) {} // Can throw
 };
 
+struct Cleanup
+{
+  ~Cleanup() {}
+};
+
+struct W {
+  W(Cleanup c = {}) noexcept(false);
+};
+
 
 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: 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: 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: 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
 
 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
 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
 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
+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
 
-void f(S s1, T t1, U u1, V v1) { // ok, ok, ok, ok
+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: 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: 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: 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
 
 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
 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
 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
+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
 };
 
 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 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
 
   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: 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: 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: 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