1 // NOTE: Assertions have been autogenerated by utils/update_cc_test_checks.py UTC_ARGS: --version 3
2 // RUN: %clang_cc1 -triple=x86_64 -emit-llvm -o - -std=c23 %s | FileCheck %s
3
4 /* WG14 N2819: No
5 * Disambiguate the storage class of some compound literals
6 */
7
8 int *escaped;
9 // CHECK-LABEL: define dso_local i32 @f(
10 // CHECK-SAME: ptr noundef [[PTR:%.*]]) #[[ATTR0:[0-9]+]] {
11 // CHECK-NEXT: entry:
12 // CHECK-NEXT: [[PTR_ADDR:%.*]] = alloca ptr, align 8
13 // CHECK-NEXT: store ptr [[PTR]], ptr [[PTR_ADDR]], align 8
14 // CHECK-NEXT: [[TMP0:%.*]] = load ptr, ptr [[PTR_ADDR]], align 8
15 // CHECK-NEXT: store ptr [[TMP0]], ptr @escaped, align 8
16 // CHECK-NEXT: ret i32 1
17 //
f(int * ptr)18 int f(int *ptr) { escaped = ptr; return 1; }
19
20 // CHECK-LABEL: define dso_local i32 @g(
21 // CHECK-SAME: ptr noundef [[PARA:%.*]]) #[[ATTR0]] {
22 // CHECK-NEXT: entry:
23 // CHECK-NEXT: [[PARA_ADDR:%.*]] = alloca ptr, align 8
24 // CHECK-NEXT: store ptr [[PARA]], ptr [[PARA_ADDR]], align 8
25 // CHECK-NEXT: [[CALL:%.*]] = call i32 @f(ptr noundef @.compoundliteral)
26 // CHECK-NEXT: [[TMP0:%.*]] = zext i32 [[CALL]] to i64
27 // CHECK-NEXT: ret i32 0
28 //
29 // FIXME: notice the we are using the global .compoundliteral object, not
30 // allocating a new object on each call to g(). That's what was clarified by
31 // N2819.
g(char * para[f ((int[27]){ 0 })])32 int g(char *para [f(( int [27]) { 0 })]) {
33 return 0;
34 }
35
36 // CHECK-LABEL: define dso_local i32 @main(
37 // CHECK-SAME: ) #[[ATTR0]] {
38 // CHECK-NEXT: entry:
39 // CHECK-NEXT: [[RETVAL:%.*]] = alloca i32, align 4
40 // CHECK-NEXT: store i32 0, ptr [[RETVAL]], align 4
41 // CHECK-NEXT: [[CALL:%.*]] = call i32 @g(ptr noundef null)
42 // CHECK-NEXT: [[TMP0:%.*]] = load ptr, ptr @escaped, align 8
43 // CHECK-NEXT: store i32 12, ptr [[TMP0]], align 4
44 // CHECK-NEXT: [[TMP1:%.*]] = load ptr, ptr @escaped, align 8
45 // CHECK-NEXT: [[TMP2:%.*]] = load i32, ptr [[TMP1]], align 4
46 // CHECK-NEXT: ret i32 [[TMP2]]
47 //
main()48 int main() {
49 // Sets 'escaped' to the address of the array created by the compound literal.
50 g(nullptr);
51
52 // The lifetime of that object should have ended when g() returned, so this
53 // should be a use-after-free.
54 *escaped = 12;
55 return *escaped;
56 }
57
58