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Diffstat (limited to '')
-rw-r--r-- | compiler/rustc_const_eval/src/might_permit_raw_init.rs | 40 |
1 files changed, 40 insertions, 0 deletions
diff --git a/compiler/rustc_const_eval/src/might_permit_raw_init.rs b/compiler/rustc_const_eval/src/might_permit_raw_init.rs new file mode 100644 index 000000000..f971c2238 --- /dev/null +++ b/compiler/rustc_const_eval/src/might_permit_raw_init.rs @@ -0,0 +1,40 @@ +use crate::const_eval::CompileTimeInterpreter; +use crate::interpret::{InterpCx, MemoryKind, OpTy}; +use rustc_middle::ty::layout::LayoutCx; +use rustc_middle::ty::{layout::TyAndLayout, ParamEnv, TyCtxt}; +use rustc_session::Limit; +use rustc_target::abi::InitKind; + +pub fn might_permit_raw_init<'tcx>( + tcx: TyCtxt<'tcx>, + ty: TyAndLayout<'tcx>, + kind: InitKind, +) -> bool { + let strict = tcx.sess.opts.unstable_opts.strict_init_checks; + + if strict { + let machine = CompileTimeInterpreter::new(Limit::new(0), false); + + let mut cx = InterpCx::new(tcx, rustc_span::DUMMY_SP, ParamEnv::reveal_all(), machine); + + let allocated = cx + .allocate(ty, MemoryKind::Machine(crate::const_eval::MemoryKind::Heap)) + .expect("OOM: failed to allocate for uninit check"); + + if kind == InitKind::Zero { + cx.write_bytes_ptr( + allocated.ptr, + std::iter::repeat(0_u8).take(ty.layout.size().bytes_usize()), + ) + .expect("failed to write bytes for zero valid check"); + } + + let ot: OpTy<'_, _> = allocated.into(); + + // Assume that if it failed, it's a validation failure. + cx.validate_operand(&ot).is_ok() + } else { + let layout_cx = LayoutCx { tcx, param_env: ParamEnv::reveal_all() }; + ty.might_permit_raw_init(&layout_cx, kind) + } +} |