diff options
| -rw-r--r-- | src/librustc_mir/borrow_check.rs | 14 | ||||
| -rw-r--r-- | src/test/ui/lifetime-errors/liveness-assign-imm-local-notes.rs | 54 | ||||
| -rw-r--r-- | src/test/ui/lifetime-errors/liveness-assign-imm-local-notes.stderr | 64 |
3 files changed, 126 insertions, 6 deletions
diff --git a/src/librustc_mir/borrow_check.rs b/src/librustc_mir/borrow_check.rs index 57735807edb..76968a871c9 100644 --- a/src/librustc_mir/borrow_check.rs +++ b/src/librustc_mir/borrow_check.rs @@ -1586,13 +1586,15 @@ impl<'cx, 'gcx, 'tcx> MirBorrowckCtxt<'cx, 'gcx, 'tcx> { _context: Context, (lvalue, span): (&Lvalue<'tcx>, Span), assigned_span: Span) { - self.tcx.cannot_reassign_immutable(span, + let mut err = self.tcx.cannot_reassign_immutable(span, &self.describe_lvalue(lvalue), - Origin::Mir) - .span_label(span, "cannot assign twice to immutable variable") - .span_label(assigned_span, format!("first assignment to `{}`", - self.describe_lvalue(lvalue))) - .emit(); + Origin::Mir); + err.span_label(span, "cannot assign twice to immutable variable"); + if span != assigned_span { + err.span_label(assigned_span, format!("first assignment to `{}`", + self.describe_lvalue(lvalue))); + } + err.emit(); } fn report_assignment_to_static(&mut self, diff --git a/src/test/ui/lifetime-errors/liveness-assign-imm-local-notes.rs b/src/test/ui/lifetime-errors/liveness-assign-imm-local-notes.rs new file mode 100644 index 00000000000..d4ef87cdd76 --- /dev/null +++ b/src/test/ui/lifetime-errors/liveness-assign-imm-local-notes.rs @@ -0,0 +1,54 @@ +// Copyright 2012 The Rust Project Developers. See the COPYRIGHT +// file at the top-level directory of this distribution and at +// http://rust-lang.org/COPYRIGHT. +// +// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or +// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license +// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. + +// FIXME: Change to UI Test +// Check notes are placed on an assignment that can actually preceed the current assigmnent +// Don't emmit a first assignment for assignment in a loop. + +// compile-flags: -Zborrowck=compare + +fn test() { + let x; + if true { + x = 1; + } else { + x = 2; + x = 3; //~ ERROR (Ast) [E0384] + //~^ ERROR (Mir) [E0384] + } +} + +fn test_in_loop() { + loop { + let x; + if true { + x = 1; + } else { + x = 2; + x = 3; //~ ERROR (Ast) [E0384] + //~^ ERROR (Mir) [E0384] + } + } +} + +fn test_using_loop() { + let x; + loop { + if true { + x = 1; //~ ERROR (Ast) [E0384] + //~^ ERROR (Mir) [E0384] + } else { + x = 2; //~ ERROR (Ast) [E0384] + //~^ ERROR (Mir) [E0384] + } + } +} + +fn main() {} diff --git a/src/test/ui/lifetime-errors/liveness-assign-imm-local-notes.stderr b/src/test/ui/lifetime-errors/liveness-assign-imm-local-notes.stderr new file mode 100644 index 00000000000..b8f738e445e --- /dev/null +++ b/src/test/ui/lifetime-errors/liveness-assign-imm-local-notes.stderr @@ -0,0 +1,64 @@ +error[E0384]: cannot assign twice to immutable variable `x` (Ast) + --> $DIR/liveness-assign-imm-local-notes.rs:23:9 + | +22 | x = 2; + | ----- first assignment to `x` +23 | x = 3; //~ ERROR (Ast) [E0384] + | ^^^^^ cannot assign twice to immutable variable + +error[E0384]: cannot assign twice to immutable variable `x` (Ast) + --> $DIR/liveness-assign-imm-local-notes.rs:35:13 + | +34 | x = 2; + | ----- first assignment to `x` +35 | x = 3; //~ ERROR (Ast) [E0384] + | ^^^^^ cannot assign twice to immutable variable + +error[E0384]: cannot assign twice to immutable variable `x` (Ast) + --> $DIR/liveness-assign-imm-local-notes.rs:45:13 + | +45 | x = 1; //~ ERROR (Ast) [E0384] + | ^^^^^ cannot assign twice to immutable variable + +error[E0384]: cannot assign twice to immutable variable `x` (Ast) + --> $DIR/liveness-assign-imm-local-notes.rs:48:13 + | +45 | x = 1; //~ ERROR (Ast) [E0384] + | ----- first assignment to `x` +... +48 | x = 2; //~ ERROR (Ast) [E0384] + | ^^^^^ cannot assign twice to immutable variable + +error[E0384]: cannot assign twice to immutable variable `x` (Mir) + --> $DIR/liveness-assign-imm-local-notes.rs:23:9 + | +22 | x = 2; + | ----- first assignment to `x` +23 | x = 3; //~ ERROR (Ast) [E0384] + | ^^^^^ cannot assign twice to immutable variable + +error[E0384]: cannot assign twice to immutable variable `x` (Mir) + --> $DIR/liveness-assign-imm-local-notes.rs:35:13 + | +34 | x = 2; + | ----- first assignment to `x` +35 | x = 3; //~ ERROR (Ast) [E0384] + | ^^^^^ cannot assign twice to immutable variable + +error[E0384]: cannot assign twice to immutable variable `x` (Mir) + --> $DIR/liveness-assign-imm-local-notes.rs:45:13 + | +45 | x = 1; //~ ERROR (Ast) [E0384] + | ^^^^^ cannot assign twice to immutable variable + +error[E0384]: cannot assign twice to immutable variable `x` (Mir) + --> $DIR/liveness-assign-imm-local-notes.rs:48:13 + | +45 | x = 1; //~ ERROR (Ast) [E0384] + | ----- first assignment to `x` +... +48 | x = 2; //~ ERROR (Ast) [E0384] + | ^^^^^ cannot assign twice to immutable variable + +error: aborting due to 8 previous errors + |