// RUN: %clang_asan -O2 %s -o %t // RUN: %run %t 2>&1 | FileCheck --check-prefix=CHECK-NOSCRIBBLE %s // RUN: %env MallocScribble=1 MallocPreScribble=1 %run %t 2>&1 | FileCheck --check-prefix=CHECK-SCRIBBLE %s // RUN: %env_asan_opts=max_free_fill_size=4096 %run %t 2>&1 | FileCheck --check-prefix=CHECK-SCRIBBLE %s #include #include #include #include struct Isa { const char *class_name; }; struct MyClass { long padding; Isa *isa; long data; void print_my_class_name(); }; __attribute__((no_sanitize("address"))) void MyClass::print_my_class_name() { fprintf(stderr, "this = %p\n", this); fprintf(stderr, "padding = 0x%lx\n", this->padding); fprintf(stderr, "isa = %p\n", this->isa); if ((uint32_t)(uintptr_t)this->isa != 0x55555555) { fprintf(stderr, "class name: %s\n", this->isa->class_name); } } int main() { Isa *my_class_isa = (Isa *)malloc(sizeof(Isa)); memset(my_class_isa, 0x77, sizeof(Isa)); my_class_isa->class_name = "MyClass"; MyClass *my_object = (MyClass *)malloc(sizeof(MyClass)); memset(my_object, 0x88, sizeof(MyClass)); my_object->isa = my_class_isa; my_object->data = 42; my_object->print_my_class_name(); // CHECK-SCRIBBLE: class name: MyClass // CHECK-NOSCRIBBLE: class name: MyClass free(my_object); my_object->print_my_class_name(); // CHECK-NOSCRIBBLE: class name: MyClass // CHECK-SCRIBBLE: isa = {{(0x)?}}{{5555555555555555|55555555}} fprintf(stderr, "okthxbai!\n"); // CHECK-SCRIBBLE: okthxbai! // CHECK-NOSCRIBBLE: okthxbai! free(my_class_isa); }