From 35c9e5f1229d8b634ebd98c49e35c74e237e17f7 Mon Sep 17 00:00:00 2001 From: Yuki Okushi Date: Sun, 1 Sep 2019 22:05:50 +0900 Subject: [PATCH] Fix const_err with `-(-0.0)` --- src/librustc_mir/transform/const_prop.rs | 14 +------------- src/test/ui/consts/const-err2.rs | 1 - src/test/ui/consts/const-err2.stderr | 20 +++++++------------- src/test/ui/consts/issue-64059.rs | 5 +++++ 4 files changed, 13 insertions(+), 27 deletions(-) create mode 100644 src/test/ui/consts/issue-64059.rs diff --git a/src/librustc_mir/transform/const_prop.rs b/src/librustc_mir/transform/const_prop.rs index f261fdc268b..00118c05c94 100644 --- a/src/librustc_mir/transform/const_prop.rs +++ b/src/librustc_mir/transform/const_prop.rs @@ -6,7 +6,7 @@ use std::cell::Cell; use rustc::hir::def::DefKind; use rustc::mir::{ AggregateKind, Constant, Location, Place, PlaceBase, Body, Operand, Rvalue, - Local, NullOp, UnOp, StatementKind, Statement, LocalKind, Static, StaticKind, + Local, NullOp, StatementKind, Statement, LocalKind, Static, StaticKind, TerminatorKind, Terminator, ClearCrossCrate, SourceInfo, BinOp, ProjectionElem, SourceScope, SourceScopeLocalData, LocalDecl, }; @@ -407,18 +407,6 @@ impl<'mir, 'tcx> ConstPropagator<'mir, 'tcx> { let arg = self.eval_operand(arg, source_info)?; let val = self.use_ecx(source_info, |this| { let prim = this.ecx.read_immediate(arg)?; - match op { - UnOp::Neg => { - // Need to do overflow check here: For actual CTFE, MIR - // generation emits code that does this before calling the op. - if prim.to_bits()? == (1 << (prim.layout.size.bits() - 1)) { - throw_panic!(OverflowNeg) - } - } - UnOp::Not => { - // Cannot overflow - } - } // Now run the actual operation. this.ecx.unary_op(op, prim) })?; diff --git a/src/test/ui/consts/const-err2.rs b/src/test/ui/consts/const-err2.rs index a5f685a159b..5aab1972a9b 100644 --- a/src/test/ui/consts/const-err2.rs +++ b/src/test/ui/consts/const-err2.rs @@ -13,7 +13,6 @@ fn black_box(_: T) { fn main() { let a = -std::i8::MIN; - //~^ ERROR const_err let b = 200u8 + 200u8 + 200u8; //~^ ERROR const_err let c = 200u8 * 4; diff --git a/src/test/ui/consts/const-err2.stderr b/src/test/ui/consts/const-err2.stderr index 659c3afc618..63d037764a1 100644 --- a/src/test/ui/consts/const-err2.stderr +++ b/src/test/ui/consts/const-err2.stderr @@ -1,8 +1,8 @@ error: this expression will panic at runtime - --> $DIR/const-err2.rs:15:13 + --> $DIR/const-err2.rs:16:13 | -LL | let a = -std::i8::MIN; - | ^^^^^^^^^^^^^ attempt to negate with overflow +LL | let b = 200u8 + 200u8 + 200u8; + | ^^^^^^^^^^^^^ attempt to add with overflow | note: lint level defined here --> $DIR/const-err2.rs:8:9 @@ -11,28 +11,22 @@ LL | #![deny(const_err)] | ^^^^^^^^^ error: this expression will panic at runtime - --> $DIR/const-err2.rs:17:13 - | -LL | let b = 200u8 + 200u8 + 200u8; - | ^^^^^^^^^^^^^ attempt to add with overflow - -error: this expression will panic at runtime - --> $DIR/const-err2.rs:19:13 + --> $DIR/const-err2.rs:18:13 | LL | let c = 200u8 * 4; | ^^^^^^^^^ attempt to multiply with overflow error: this expression will panic at runtime - --> $DIR/const-err2.rs:21:13 + --> $DIR/const-err2.rs:20:13 | LL | let d = 42u8 - (42u8 + 1); | ^^^^^^^^^^^^^^^^^ attempt to subtract with overflow error: index out of bounds: the len is 1 but the index is 1 - --> $DIR/const-err2.rs:23:14 + --> $DIR/const-err2.rs:22:14 | LL | let _e = [5u8][1]; | ^^^^^^^^ -error: aborting due to 5 previous errors +error: aborting due to 4 previous errors diff --git a/src/test/ui/consts/issue-64059.rs b/src/test/ui/consts/issue-64059.rs new file mode 100644 index 00000000000..c4c895fef66 --- /dev/null +++ b/src/test/ui/consts/issue-64059.rs @@ -0,0 +1,5 @@ +// run-pass + +fn main() { + let _ = -(-0.0); +}