Fix crash when analyzing anonymous lambda fns

Author: Discookie

clang-tools-extra/clang-tidy/bugprone/NullCheckAfterDereferenceCheck.cpp

@@ -124,8 +124,10 @@ void NullCheckAfterDereferenceCheck::registerMatchers(MatchFinder *Finder) {
                               // well supported by the check.
                               unless(hasDeclContext(cxxRecordDecl(isLambda()))),
                               hasBody(containsPointerValue)),
-                 cxxConstructorDecl(hasAnyConstructorInitializer(
-                     withInitializer(containsPointerValue)))))
+                 cxxConstructorDecl(
+                     unless(hasDeclContext(cxxRecordDecl(isLambda()))),
+                     hasAnyConstructorInitializer(
+                         withInitializer(containsPointerValue)))))
           .bind(FuncID),
       this);
 }

clang-tools-extra/test/clang-tidy/checkers/bugprone/null-check-after-dereference.cpp

@@ -4,57 +4,46 @@ struct S {
   int a;
 };
 
-int warning_deref(int *p) {
+void warning_deref(int *p) {
   *p = 42;
 
   if (p) {
     // CHECK-MESSAGES: :[[@LINE-1]]:7: warning: pointer value is checked even though it cannot be null at this point [bugprone-null-check-after-dereference]
     // CHECK-MESSAGES: :[[@LINE-4]]:3: note: one of the locations where the pointer's value cannot be null
   // FIXME: If there's a direct path, make the error message more precise, ie. remove `one of the locations`
     *p += 20;
-    return *p;
-  } else {
-    return 0;
   }
 }
 
-int warning_member(S *q) {
+void warning_member(S *q) {
   q->a = 42;
 
   if (q) {
     // CHECK-MESSAGES: :[[@LINE-1]]:7: warning: pointer value is checked even though it cannot be null at this point
     // CHECK-MESSAGES: :[[@LINE-4]]:3: note: one of the locations where the pointer's value cannot be null
     q->a += 20;
-    return q->a;
-  } else {
-    return 0;
   }
 }
 
-int negative_warning(int *p) {
+void negative_warning(int *p) {
   *p = 42;
 
   if (!p) {
     // CHECK-MESSAGES: :[[@LINE-1]]:8: warning: pointer value is checked even though it cannot be null at this point
     // CHECK-MESSAGES: :[[@LINE-4]]:3: note: one of the locations where the pointer's value cannot be null
-    return 0;
-  } else {
-    *p += 20;
-    return *p;
+    return;
   }
+  
+  *p += 20;
 }
 
-int no_warning(int *p, bool b) {
+void no_warning(int *p, bool b) {
   if (b) {
     *p = 42;
   }
 
   if (p) {
-    // CHECK-MESSAGES-NOT: :[[@LINE-1]]:7: warning: pointer value is checked even though it cannot be null at this point 
     *p += 20;
-    return *p;
-  } else {
-    return 0;
   }
 }
 
@@ -195,18 +184,6 @@ int chained_references(int *a, int *b, int *c, int *d, int *e) {
   }
 
   if (c) {
-    // CHECK-MESSAGES: :[[@LINE-1]]:7: warning: pointer value is checked even though it cannot be null at this point
-    // CHECK-MESSAGES: :[[@LINE-5]]:5: note: one of the locations where the pointer's value cannot be null
-    *d = 42;
-  }
-
-  if (d) {
-    // CHECK-MESSAGES: :[[@LINE-1]]:7: warning: pointer value is checked even though it cannot be null at this point
-    // CHECK-MESSAGES: :[[@LINE-5]]:5: note: one of the locations where the pointer's value cannot be null
-    *e = 42;
-  }
-
-  if (e) {
     // CHECK-MESSAGES: :[[@LINE-1]]:7: warning: pointer value is checked even though it cannot be null at this point
     // CHECK-MESSAGES: :[[@LINE-5]]:5: note: one of the locations where the pointer's value cannot be null
     return *a;
@@ -282,6 +259,12 @@ int cxx17_crash(int *p) {
   return 0;
 }
 
+// In an earlier version, the check would crash when encountering anonymous lambdas.
+void lambda_crash(int *p) {
+  auto f = [p](){ *p = 42; };
+  f();
+}
+
 int note_tags() {
   // FIXME: Note tags are not appended to declarations
   int *ptr = nullptr;