clang/test/CodeGenCXX/catch-nullptr-and-nonzero-offset-in-offsetof-idiom.cpp

   1 // NOTE: Assertions have been autogenerated by utils/update_cc_test_checks.py
   2 // RUN: %clang_cc1 -x c++ -emit-llvm %s -o - -triple x86_64-linux-gnu | FileCheck %s
   3 // RUN: %clang_cc1 -x c++ -fsanitize=pointer-overflow -fno-sanitize-recover=pointer-overflow -emit-llvm %s -o - -triple x86_64-linux-gnu | FileCheck %s
   4
   5 #include <stdint.h>
   6
   7 struct S {
   8   int x, y;
   9 };
  10
  11 // CHECK-LABEL: @_Z23get_offset_of_y_naivelyv(
  12 // CHECK-NEXT:  entry:
  13 // CHECK-NEXT:    ret i64 ptrtoint (ptr getelementptr inbounds ([[STRUCT_S:%.*]], ptr null, i32 0, i32 1) to i64)
  14 //
  15 uintptr_t get_offset_of_y_naively() {
  16   return ((uintptr_t)(&(((S *)nullptr)->y)));
  17 }
  18
  19 // CHECK-LABEL: @_Z27get_offset_of_y_via_builtinv(
  20 // CHECK-NEXT:  entry:
  21 // CHECK-NEXT:    ret i64 4
  22 //
  23 uintptr_t get_offset_of_y_via_builtin() {
  24   return __builtin_offsetof(S, y);
  25 }