From 094d67ee37d37caa2ebd755fa39ebcaa7b586b26 Mon Sep 17 00:00:00 2001
From: Basile Desloges <basile.desloges@gmail.com>
Date: Thu, 16 Nov 2017 16:52:04 +0100
Subject: [PATCH 1/3] mir-borrowck: Remove parens in the lvalue description of
a deref
---
src/librustc_mir/borrow_check.rs | 3 +--
.../borrowck/borrowck-closures-mut-and-imm.rs | 4 ++--
.../compile-fail/borrowck/borrowck-describe-lvalue.rs | 10 +++++-----
src/test/compile-fail/coerce-overloaded-autoderef.rs | 8 ++++----
.../compile-fail/mut-pattern-internal-mutability.rs | 2 +-
src/test/ui/nll/get_default.stderr | 2 +-
6 files changed, 14 insertions(+), 15 deletions(-)
diff --git a/src/librustc_mir/borrow_check.rs b/src/librustc_mir/borrow_check.rs
index cdac72b6dffb0..486f95f68ea78 100644
--- a/src/librustc_mir/borrow_check.rs
+++ b/src/librustc_mir/borrow_check.rs
@@ -1601,9 +1601,8 @@ impl<'cx, 'gcx, 'tcx> MirBorrowckCtxt<'cx, 'gcx, 'tcx> {
if autoderef {
self.append_lvalue_to_string(&proj.base, buf, Some(autoderef));
} else {
- buf.push_str(&"(*");
+ buf.push_str(&"*");
self.append_lvalue_to_string(&proj.base, buf, Some(autoderef));
- buf.push_str(&")");
}
},
ProjectionElem::Downcast(..) => {
diff --git a/src/test/compile-fail/borrowck/borrowck-closures-mut-and-imm.rs b/src/test/compile-fail/borrowck/borrowck-closures-mut-and-imm.rs
index 0b6b9bf7d484d..c40470a927cd7 100644
--- a/src/test/compile-fail/borrowck/borrowck-closures-mut-and-imm.rs
+++ b/src/test/compile-fail/borrowck/borrowck-closures-mut-and-imm.rs
@@ -70,7 +70,7 @@ fn f() {
let c1 = || get(&*x);
*x = 5; //[ast]~ ERROR cannot assign
//[mir]~^ ERROR cannot assign to `*x` because it is borrowed (Ast)
- //[mir]~| ERROR cannot assign to `(*x)` because it is borrowed (Mir)
+ //[mir]~| ERROR cannot assign to `*x` because it is borrowed (Mir)
}
fn g() {
@@ -82,7 +82,7 @@ fn g() {
let c1 = || get(&*x.f);
*x.f = 5; //[ast]~ ERROR cannot assign to `*x.f`
//[mir]~^ ERROR cannot assign to `*x.f` because it is borrowed (Ast)
- //[mir]~| ERROR cannot assign to `(*x.f)` because it is borrowed (Mir)
+ //[mir]~| ERROR cannot assign to `*x.f` because it is borrowed (Mir)
}
fn h() {
diff --git a/src/test/compile-fail/borrowck/borrowck-describe-lvalue.rs b/src/test/compile-fail/borrowck/borrowck-describe-lvalue.rs
index d1cf08ac75463..009819f0bb576 100644
--- a/src/test/compile-fail/borrowck/borrowck-describe-lvalue.rs
+++ b/src/test/compile-fail/borrowck/borrowck-describe-lvalue.rs
@@ -252,7 +252,7 @@ fn main() {
fn bump<'a>(mut block: &mut Block<'a>) {
let x = &mut block;
let p: &'a u8 = &*block.current;
- //[mir]~^ ERROR cannot borrow `(*block.current)` as immutable because it is also borrowed as mutable (Mir)
+ //[mir]~^ ERROR cannot borrow `*block.current` as immutable because it is also borrowed as mutable (Mir)
// No errors in AST because of issue rust#38899
}
}
@@ -266,7 +266,7 @@ fn main() {
unsafe fn bump2(mut block: *mut Block2) {
let x = &mut block;
let p : *const u8 = &*(*block).current;
- //[mir]~^ ERROR cannot borrow `(*block.current)` as immutable because it is also borrowed as mutable (Mir)
+ //[mir]~^ ERROR cannot borrow `*block.current` as immutable because it is also borrowed as mutable (Mir)
// No errors in AST because of issue rust#38899
}
}
@@ -279,7 +279,7 @@ fn main() {
//[ast]~^ ERROR cannot use `v[..].y` because it was mutably borrowed
//[mir]~^^ ERROR cannot use `v[..].y` because it was mutably borrowed (Ast)
//[mir]~| ERROR cannot use `v[..].y` because it was mutably borrowed (Mir)
- //[mir]~| ERROR cannot use `(*v)` because it was mutably borrowed (Mir)
+ //[mir]~| ERROR cannot use `*v` because it was mutably borrowed (Mir)
}
// Field of constant index
{
@@ -300,7 +300,7 @@ fn main() {
let y = &mut x;
&mut x; //[ast]~ ERROR cannot borrow `**x` as mutable more than once at a time
//[mir]~^ ERROR cannot borrow `**x` as mutable more than once at a time (Ast)
- //[mir]~| ERROR cannot borrow `(*x)` as mutable more than once at a time (Mir)
+ //[mir]~| ERROR cannot borrow `*x` as mutable more than once at a time (Mir)
*y = 1;
};
}
@@ -312,7 +312,7 @@ fn main() {
let y = &mut x;
&mut x; //[ast]~ ERROR cannot borrow `**x` as mutable more than once at a time
//[mir]~^ ERROR cannot borrow `**x` as mutable more than once at a time (Ast)
- //[mir]~| ERROR cannot borrow `(*x)` as mutable more than once at a time (Mir)
+ //[mir]~| ERROR cannot borrow `*x` as mutable more than once at a time (Mir)
*y = 1;
}
};
diff --git a/src/test/compile-fail/coerce-overloaded-autoderef.rs b/src/test/compile-fail/coerce-overloaded-autoderef.rs
index 43b771ce5dbed..1060c3f468ce9 100644
--- a/src/test/compile-fail/coerce-overloaded-autoderef.rs
+++ b/src/test/compile-fail/coerce-overloaded-autoderef.rs
@@ -22,7 +22,7 @@ fn double_mut_borrow<T>(x: &mut Box<T>) {
let z = borrow_mut(x);
//[ast]~^ ERROR cannot borrow `*x` as mutable more than once at a time
//[mir]~^^ ERROR cannot borrow `*x` as mutable more than once at a time (Ast)
- //[mir]~| ERROR cannot borrow `(*x)` as mutable more than once at a time (Mir)
+ //[mir]~| ERROR cannot borrow `*x` as mutable more than once at a time (Mir)
}
fn double_imm_borrow(x: &mut Box<i32>) {
@@ -31,21 +31,21 @@ fn double_imm_borrow(x: &mut Box<i32>) {
**x += 1;
//[ast]~^ ERROR cannot assign to `**x` because it is borrowed
//[mir]~^^ ERROR cannot assign to `**x` because it is borrowed (Ast)
- //[mir]~| ERROR cannot assign to `(*(*x))` because it is borrowed (Mir)
+ //[mir]~| ERROR cannot assign to `**x` because it is borrowed (Mir)
}
fn double_mut_borrow2<T>(x: &mut Box<T>) {
borrow_mut2(x, x);
//[ast]~^ ERROR cannot borrow `*x` as mutable more than once at a time
//[mir]~^^ ERROR cannot borrow `*x` as mutable more than once at a time (Ast)
- //[mir]~| ERROR cannot borrow `(*x)` as mutable more than once at a time (Mir)
+ //[mir]~| ERROR cannot borrow `*x` as mutable more than once at a time (Mir)
}
fn double_borrow2<T>(x: &mut Box<T>) {
borrow2(x, x);
//[ast]~^ ERROR cannot borrow `*x` as immutable because it is also borrowed as mutable
//[mir]~^^ ERROR cannot borrow `*x` as immutable because it is also borrowed as mutable (Ast)
- //[mir]~| ERROR cannot borrow `(*x)` as immutable because it is also borrowed as mutable (Mir)
+ //[mir]~| ERROR cannot borrow `*x` as immutable because it is also borrowed as mutable (Mir)
}
pub fn main() {}
diff --git a/src/test/compile-fail/mut-pattern-internal-mutability.rs b/src/test/compile-fail/mut-pattern-internal-mutability.rs
index 1c7bc9d73037c..a1b7a314f216d 100644
--- a/src/test/compile-fail/mut-pattern-internal-mutability.rs
+++ b/src/test/compile-fail/mut-pattern-internal-mutability.rs
@@ -27,5 +27,5 @@ fn main() {
let &mut ref x = foo;
*foo += 1; //[ast]~ ERROR cannot assign to `*foo` because it is borrowed
//[mir]~^ ERROR cannot assign to `*foo` because it is borrowed (Ast)
- //[mir]~| ERROR cannot assign to `(*foo)` because it is borrowed (Mir)
+ //[mir]~| ERROR cannot assign to `*foo` because it is borrowed (Mir)
}
diff --git a/src/test/ui/nll/get_default.stderr b/src/test/ui/nll/get_default.stderr
index 9586f42672034..8e1e9faef2f00 100644
--- a/src/test/ui/nll/get_default.stderr
+++ b/src/test/ui/nll/get_default.stderr
@@ -34,7 +34,7 @@ error[E0502]: cannot borrow `*map` as mutable because it is also borrowed as imm
51 | }
| - immutable borrow ends here
-error[E0502]: cannot borrow `(*map)` as mutable because it is also borrowed as immutable (Mir)
+error[E0502]: cannot borrow `*map` as mutable because it is also borrowed as immutable (Mir)
--> $DIR/get_default.rs:43:17
|
41 | match map.get() {
From e5d291afbfd253cdca60bcf83f2afb2b5719c6ba Mon Sep 17 00:00:00 2001
From: Basile Desloges <basile.desloges@gmail.com>
Date: Thu, 16 Nov 2017 17:06:48 +0100
Subject: [PATCH 2/3] mir-borrowck: Use bool for autoderef in
append_lvalue_to_string()
---
src/librustc_mir/borrow_check.rs | 18 ++++++++----------
1 file changed, 8 insertions(+), 10 deletions(-)
diff --git a/src/librustc_mir/borrow_check.rs b/src/librustc_mir/borrow_check.rs
index 486f95f68ea78..b1fa9ba48485f 100644
--- a/src/librustc_mir/borrow_check.rs
+++ b/src/librustc_mir/borrow_check.rs
@@ -1577,7 +1577,7 @@ impl<'cx, 'gcx, 'tcx> MirBorrowckCtxt<'cx, 'gcx, 'tcx> {
// End-user visible description of `lvalue`
fn describe_lvalue(&self, lvalue: &Lvalue<'tcx>) -> String {
let mut buf = String::new();
- self.append_lvalue_to_string(lvalue, &mut buf, None);
+ self.append_lvalue_to_string(lvalue, &mut buf, false);
buf
}
@@ -1585,7 +1585,7 @@ impl<'cx, 'gcx, 'tcx> MirBorrowckCtxt<'cx, 'gcx, 'tcx> {
fn append_lvalue_to_string(&self,
lvalue: &Lvalue<'tcx>,
buf: &mut String,
- autoderef: Option<bool>) {
+ mut autoderef: bool) {
match *lvalue {
Lvalue::Local(local) => {
self.append_local_to_string(local, buf, "_");
@@ -1594,19 +1594,17 @@ impl<'cx, 'gcx, 'tcx> MirBorrowckCtxt<'cx, 'gcx, 'tcx> {
buf.push_str(&format!("{}", &self.tcx.item_name(static_.def_id)));
}
Lvalue::Projection(ref proj) => {
- let mut autoderef = autoderef.unwrap_or(false);
-
match proj.elem {
ProjectionElem::Deref => {
if autoderef {
- self.append_lvalue_to_string(&proj.base, buf, Some(autoderef));
+ self.append_lvalue_to_string(&proj.base, buf, autoderef);
} else {
buf.push_str(&"*");
- self.append_lvalue_to_string(&proj.base, buf, Some(autoderef));
+ self.append_lvalue_to_string(&proj.base, buf, autoderef);
}
},
ProjectionElem::Downcast(..) => {
- self.append_lvalue_to_string(&proj.base, buf, Some(autoderef));
+ self.append_lvalue_to_string(&proj.base, buf, autoderef);
},
ProjectionElem::Field(field, _ty) => {
autoderef = true;
@@ -1617,14 +1615,14 @@ impl<'cx, 'gcx, 'tcx> MirBorrowckCtxt<'cx, 'gcx, 'tcx> {
if is_projection_from_ty_closure {
buf.push_str(&format!("{}", field_name));
} else {
- self.append_lvalue_to_string(&proj.base, buf, Some(autoderef));
+ self.append_lvalue_to_string(&proj.base, buf, autoderef);
buf.push_str(&format!(".{}", field_name));
}
},
ProjectionElem::Index(index) => {
autoderef = true;
- self.append_lvalue_to_string(&proj.base, buf, Some(autoderef));
+ self.append_lvalue_to_string(&proj.base, buf, autoderef);
buf.push_str("[");
self.append_local_to_string(index, buf, "..");
buf.push_str("]");
@@ -1634,7 +1632,7 @@ impl<'cx, 'gcx, 'tcx> MirBorrowckCtxt<'cx, 'gcx, 'tcx> {
// Since it isn't possible to borrow an element on a particular index and
// then use another while the borrow is held, don't output indices details
// to avoid confusing the end-user
- self.append_lvalue_to_string(&proj.base, buf, Some(autoderef));
+ self.append_lvalue_to_string(&proj.base, buf, autoderef);
buf.push_str(&"[..]");
},
};
From 2285e35919f5d17188401479863fdf3ac79cf5a8 Mon Sep 17 00:00:00 2001
From: Basile Desloges <basile.desloges@gmail.com>
Date: Thu, 16 Nov 2017 17:07:33 +0100
Subject: [PATCH 3/3] mir-borrowck: Use Field instead of usize for field index
in user description functions
---
src/librustc_mir/borrow_check.rs | 37 ++++++++++++++++----------------
1 file changed, 18 insertions(+), 19 deletions(-)
diff --git a/src/librustc_mir/borrow_check.rs b/src/librustc_mir/borrow_check.rs
index b1fa9ba48485f..08ccf2ebf22f6 100644
--- a/src/librustc_mir/borrow_check.rs
+++ b/src/librustc_mir/borrow_check.rs
@@ -15,7 +15,7 @@ use rustc::hir::def_id::{DefId};
use rustc::infer::{InferCtxt};
use rustc::ty::{self, TyCtxt, ParamEnv};
use rustc::ty::maps::Providers;
-use rustc::mir::{AssertMessage, BasicBlock, BorrowKind, Location, Lvalue, Local};
+use rustc::mir::{AssertMessage, BasicBlock, BorrowKind, Field, Location, Lvalue, Local};
use rustc::mir::{Mir, Mutability, Operand, Projection, ProjectionElem, Rvalue};
use rustc::mir::{Statement, StatementKind, Terminator, TerminatorKind};
use transform::nll;
@@ -1611,7 +1611,7 @@ impl<'cx, 'gcx, 'tcx> MirBorrowckCtxt<'cx, 'gcx, 'tcx> {
let is_projection_from_ty_closure = proj.base.ty(self.mir, self.tcx)
.to_ty(self.tcx).is_closure();
- let field_name = self.describe_field(&proj.base, field.index());
+ let field_name = self.describe_field(&proj.base, field);
if is_projection_from_ty_closure {
buf.push_str(&format!("{}", field_name));
} else {
@@ -1650,58 +1650,57 @@ impl<'cx, 'gcx, 'tcx> MirBorrowckCtxt<'cx, 'gcx, 'tcx> {
}
}
- // FIXME Instead of passing usize, Field should be passed
- // End-user visible description of the `field_index`nth field of `base`
- fn describe_field(&self, base: &Lvalue, field_index: usize) -> String {
+ // End-user visible description of the `field`nth field of `base`
+ fn describe_field(&self, base: &Lvalue, field: Field) -> String {
match *base {
Lvalue::Local(local) => {
let local = &self.mir.local_decls[local];
- self.describe_field_from_ty(&local.ty, field_index)
+ self.describe_field_from_ty(&local.ty, field)
},
Lvalue::Static(ref static_) => {
- self.describe_field_from_ty(&static_.ty, field_index)
+ self.describe_field_from_ty(&static_.ty, field)
},
Lvalue::Projection(ref proj) => {
match proj.elem {
ProjectionElem::Deref =>
- self.describe_field(&proj.base, field_index),
+ self.describe_field(&proj.base, field),
ProjectionElem::Downcast(def, variant_index) =>
- format!("{}", def.variants[variant_index].fields[field_index].name),
+ format!("{}", def.variants[variant_index].fields[field.index()].name),
ProjectionElem::Field(_, field_type) =>
- self.describe_field_from_ty(&field_type, field_index),
+ self.describe_field_from_ty(&field_type, field),
ProjectionElem::Index(..)
| ProjectionElem::ConstantIndex { .. }
| ProjectionElem::Subslice { .. } =>
- format!("{}", self.describe_field(&proj.base, field_index)),
+ format!("{}", self.describe_field(&proj.base, field)),
}
}
}
}
// End-user visible description of the `field_index`nth field of `ty`
- fn describe_field_from_ty(&self, ty: &ty::Ty, field_index: usize) -> String {
+ fn describe_field_from_ty(&self, ty: &ty::Ty, field: Field) -> String {
if ty.is_box() {
// If the type is a box, the field is described from the boxed type
- self.describe_field_from_ty(&ty.boxed_ty(), field_index)
+ self.describe_field_from_ty(&ty.boxed_ty(), field)
}
else {
match ty.sty {
ty::TyAdt(def, _) => {
if def.is_enum() {
- format!("{}", field_index)
+ format!("{}", field.index())
}
else {
- format!("{}", def.struct_variant().fields[field_index].name)
+ format!("{}", def.struct_variant().fields[field.index()].name)
}
},
ty::TyTuple(_, _) => {
- format!("{}", field_index)
+ format!("{}", field.index())
},
ty::TyRef(_, tnm) | ty::TyRawPtr(tnm) => {
- self.describe_field_from_ty(&tnm.ty, field_index)
+ self.describe_field_from_ty(&tnm.ty, field)
},
ty::TyArray(ty, _) | ty::TySlice(ty) => {
- self.describe_field_from_ty(&ty, field_index)
+ self.describe_field_from_ty(&ty, field)
},
ty::TyClosure(closure_def_id, _) => {
// Convert the def-id into a node-id. node-ids are only valid for
@@ -1709,7 +1708,7 @@ impl<'cx, 'gcx, 'tcx> MirBorrowckCtxt<'cx, 'gcx, 'tcx> {
// the closure comes from another crate. But in that case we wouldn't
// be borrowck'ing it, so we can just unwrap:
let node_id = self.tcx.hir.as_local_node_id(closure_def_id).unwrap();
- let freevar = self.tcx.with_freevars(node_id, |fv| fv[field_index]);
+ let freevar = self.tcx.with_freevars(node_id, |fv| fv[field.index()]);
self.tcx.hir.name(freevar.var_id()).to_string()
}