clang/test/C/drs/dr494.c

   1 /* RUN: %clang_cc1 -std=c89 %s -emit-llvm -o - | FileCheck %s
   2    RUN: %clang_cc1 -std=c99 %s -emit-llvm -o - | FileCheck %s
   3    RUN: %clang_cc1 -std=c11 %s -emit-llvm -o - | FileCheck %s
   4    RUN: %clang_cc1 -std=c17 %s -emit-llvm -o - | FileCheck %s
   5    RUN: %clang_cc1 -std=c2x %s -emit-llvm -o - | FileCheck %s
   6  */
   7
   8 /* WG14 DR494: yes
   9  * Part 1: Alignment specifier expression evaluation
  10  */
  11 void dr494(void) {
  12   int i = 12;
  13   int j = _Alignof(int [++i]);
  14   int k = sizeof(int [++i]);
  15   /* Check that we store a straight value for i and j, but have to calculate a
  16    * value for storing into k. That's because sizeof() needs to execute code to
  17    * get the correct value from a VLA, but _Alignof is not allowed to execute
  18    * the VLA extent at runtime.
  19    */
  20 /* CHECK: %[[I:.+]] = alloca i32
  21    CHECK: %[[J:.+]] = alloca i32
  22    CHECK: %[[K:.+]] = alloca i32
  23    CHECK: store i32 12, ptr %[[I]]
  24    CHECK: store i32 4, ptr %[[J]]
  25    CHECK: %[[ZERO:.+]] = load i32, ptr %[[I]]
  26    CHECK: %[[INC:.+]] = add nsw i32 %[[ZERO]], 1
  27    CHECK: store i32 %[[INC]], ptr %[[I]]
  28  */
  29 }
  30