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// compile-flags: -C no-prepopulate-passes
// Check that we use undef (and not zero) for uninitialized bytes in constants.
#![crate_type = "lib"]
use std::mem::MaybeUninit;
pub struct PartiallyUninit {
x: u32,
y: MaybeUninit<[u8; 10]>
}
// CHECK: [[FULLY_UNINIT:@[0-9]+]] = private unnamed_addr constant <{ [10 x i8] }> undef
// CHECK: [[PARTIALLY_UNINIT:@[0-9]+]] = private unnamed_addr constant <{ [16 x i8] }> <{ [16 x i8] c"\EF\BE\AD\DE\00\00\00\00\00\00\00\00\00\00\00\00" }>, align 4
// CHECK: [[FULLY_UNINIT_HUGE:@[0-9]+]] = private unnamed_addr constant <{ [16384 x i8] }> undef
// CHECK-LABEL: @fully_uninit
#[no_mangle]
pub const fn fully_uninit() -> MaybeUninit<[u8; 10]> {
const M: MaybeUninit<[u8; 10]> = MaybeUninit::uninit();
// CHECK: call void @llvm.memcpy.p0i8.p0i8.i{{(32|64)}}(i8* align 1 %1, i8* align 1 getelementptr inbounds (<{ [10 x i8] }>, <{ [10 x i8] }>* [[FULLY_UNINIT]], i32 0, i32 0, i32 0), i{{(32|64)}} 10, i1 false)
M
}
// CHECK-LABEL: @partially_uninit
#[no_mangle]
pub const fn partially_uninit() -> PartiallyUninit {
const X: PartiallyUninit = PartiallyUninit { x: 0xdeadbeef, y: MaybeUninit::uninit() };
// CHECK: call void @llvm.memcpy.p0i8.p0i8.i{{(32|64)}}(i8* align 4 %1, i8* align 4 getelementptr inbounds (<{ [16 x i8] }>, <{ [16 x i8] }>* [[PARTIALLY_UNINIT]], i32 0, i32 0, i32 0), i{{(32|64)}} 16, i1 false)
X
}
// CHECK-LABEL: @fully_uninit_huge
#[no_mangle]
pub const fn fully_uninit_huge() -> MaybeUninit<[u32; 4096]> {
const F: MaybeUninit<[u32; 4096]> = MaybeUninit::uninit();
// CHECK: call void @llvm.memcpy.p0i8.p0i8.i{{(32|64)}}(i8* align 4 %1, i8* align 4 getelementptr inbounds (<{ [16384 x i8] }>, <{ [16384 x i8] }>* [[FULLY_UNINIT_HUGE]], i32 0, i32 0, i32 0), i{{(32|64)}} 16384, i1 false)
F
}
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