diff options
5 files changed, 16 insertions, 20 deletions
diff --git a/compiler/rustc_const_eval/src/const_eval/error.rs b/compiler/rustc_const_eval/src/const_eval/error.rs index eb81f43c3fe..bba4b1815b4 100644 --- a/compiler/rustc_const_eval/src/const_eval/error.rs +++ b/compiler/rustc_const_eval/src/const_eval/error.rs @@ -15,7 +15,6 @@ use crate::interpret::{ /// The CTFE machine has some custom error kinds. #[derive(Clone, Debug)] pub enum ConstEvalErrKind { - NeedsRfc(String), ConstAccessesStatic, ModifiedGlobal, AssertFailure(AssertKind<ConstInt>), @@ -42,9 +41,6 @@ impl fmt::Display for ConstEvalErrKind { fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { use self::ConstEvalErrKind::*; match *self { - NeedsRfc(ref msg) => { - write!(f, "\"{}\" needs an rfc before being allowed inside constants", msg) - } ConstAccessesStatic => write!(f, "constant accesses static"), ModifiedGlobal => { write!(f, "modifying a static's initial value from another static's initializer") diff --git a/compiler/rustc_const_eval/src/const_eval/machine.rs b/compiler/rustc_const_eval/src/const_eval/machine.rs index 6c1e61fccca..9ea9fbe0e0e 100644 --- a/compiler/rustc_const_eval/src/const_eval/machine.rs +++ b/compiler/rustc_const_eval/src/const_eval/machine.rs @@ -269,9 +269,10 @@ impl<'mir, 'tcx> interpret::Machine<'mir, 'tcx> for CompileTimeInterpreter<'mir, ); throw_inval!(AlreadyReported(guar)); } else { + // `find_mir_or_eval_fn` checks that this is a const fn before even calling us, + // so this should be unreachable. let path = ecx.tcx.def_path_str(def.did); - Err(ConstEvalErrKind::NeedsRfc(format!("calling extern function `{}`", path)) - .into()) + bug!("trying to call extern function `{path}` at compile-time"); } } _ => Ok(ecx.tcx.instance_mir(instance)), @@ -339,11 +340,7 @@ impl<'mir, 'tcx> interpret::Machine<'mir, 'tcx> for CompileTimeInterpreter<'mir, // CTFE-specific intrinsics. let Some(ret) = target else { - return Err(ConstEvalErrKind::NeedsRfc(format!( - "calling intrinsic `{}`", - intrinsic_name - )) - .into()); + throw_unsup_format!("intrinsic `{intrinsic_name}` is not supported at compile-time"); }; match intrinsic_name { sym::ptr_guaranteed_eq | sym::ptr_guaranteed_ne => { @@ -400,11 +397,9 @@ impl<'mir, 'tcx> interpret::Machine<'mir, 'tcx> for CompileTimeInterpreter<'mir, } } _ => { - return Err(ConstEvalErrKind::NeedsRfc(format!( - "calling intrinsic `{}`", - intrinsic_name - )) - .into()); + throw_unsup_format!( + "intrinsic `{intrinsic_name}` is not supported at compile-time" + ); } } @@ -447,7 +442,7 @@ impl<'mir, 'tcx> interpret::Machine<'mir, 'tcx> for CompileTimeInterpreter<'mir, _left: &ImmTy<'tcx>, _right: &ImmTy<'tcx>, ) -> InterpResult<'tcx, (Scalar, bool, Ty<'tcx>)> { - Err(ConstEvalErrKind::NeedsRfc("pointer arithmetic or comparison".to_string()).into()) + throw_unsup_format!("pointer arithmetic or comparison is not supported at compile-time"); } fn before_terminator(ecx: &mut InterpCx<'mir, 'tcx, Self>) -> InterpResult<'tcx> { @@ -469,7 +464,8 @@ impl<'mir, 'tcx> interpret::Machine<'mir, 'tcx> for CompileTimeInterpreter<'mir, _ecx: &mut InterpCx<'mir, 'tcx, Self>, _ptr: Pointer<AllocId>, ) -> InterpResult<'tcx> { - Err(ConstEvalErrKind::NeedsRfc("exposing pointers".to_string()).into()) + // This is only reachable with -Zunleash-the-miri-inside-of-you. + throw_unsup_format!("exposing pointers is not possible at compile-time") } #[inline(always)] diff --git a/compiler/rustc_const_eval/src/interpret/machine.rs b/compiler/rustc_const_eval/src/interpret/machine.rs index 6bed8a7a007..8df6737b839 100644 --- a/compiler/rustc_const_eval/src/interpret/machine.rs +++ b/compiler/rustc_const_eval/src/interpret/machine.rs @@ -490,6 +490,7 @@ pub macro compile_time_machine(<$mir: lifetime, $tcx: lifetime>) { ) -> InterpResult<$tcx, Pointer<Option<AllocId>>> { // Allow these casts, but make the pointer not dereferenceable. // (I.e., they behave like transmutation.) + // This is correct because no pointers can ever be exposed in compile-time evaluation. Ok(Pointer::from_addr(addr)) } diff --git a/src/test/ui/consts/miri_unleashed/ptr_arith.rs b/src/test/ui/consts/miri_unleashed/ptr_arith.rs index 13e6af36e02..6a19b294585 100644 --- a/src/test/ui/consts/miri_unleashed/ptr_arith.rs +++ b/src/test/ui/consts/miri_unleashed/ptr_arith.rs @@ -8,7 +8,7 @@ static PTR_INT_CAST: () = { let x = &0 as *const _ as usize; //~^ ERROR could not evaluate static initializer - //~| "exposing pointers" needs an rfc before being allowed inside constants + //~| exposing pointers let _v = x == x; }; @@ -19,4 +19,7 @@ static PTR_INT_TRANSMUTE: () = unsafe { //~| unable to turn pointer into raw bytes }; +// I'd love to test pointer comparison, but that is not possible since +// their `PartialEq` impl is non-`const`. + fn main() {} diff --git a/src/test/ui/consts/miri_unleashed/ptr_arith.stderr b/src/test/ui/consts/miri_unleashed/ptr_arith.stderr index 00cff23fb3f..f5c5ee2b8eb 100644 --- a/src/test/ui/consts/miri_unleashed/ptr_arith.stderr +++ b/src/test/ui/consts/miri_unleashed/ptr_arith.stderr @@ -2,7 +2,7 @@ error[E0080]: could not evaluate static initializer --> $DIR/ptr_arith.rs:9:13 | LL | let x = &0 as *const _ as usize; - | ^^^^^^^^^^^^^^^^^^^^^^^ "exposing pointers" needs an rfc before being allowed inside constants + | ^^^^^^^^^^^^^^^^^^^^^^^ exposing pointers is not possible at compile-time error[E0080]: could not evaluate static initializer --> $DIR/ptr_arith.rs:17:14 |