From 5f27a25cf4eab09e70cdf81f5e548f13fa7fc289 Mon Sep 17 00:00:00 2001 From: Patrick McCarter Date: Fri, 22 Feb 2019 15:49:07 -0500 Subject: [PATCH 1/4] Invalid byte alignment expected/provided in message #58617 --- src/librustc_mir/interpret/validity.rs | 6 ++++-- src/test/ui/consts/const-eval/ub-ref.rs | 1 + src/test/ui/consts/const-eval/ub-ref.stderr | 10 +++++----- 3 files changed, 10 insertions(+), 7 deletions(-) diff --git a/src/librustc_mir/interpret/validity.rs b/src/librustc_mir/interpret/validity.rs index 8b97d9ded7449..91a43d5c991bf 100644 --- a/src/librustc_mir/interpret/validity.rs +++ b/src/librustc_mir/interpret/validity.rs @@ -357,8 +357,10 @@ impl<'rt, 'a, 'mir, 'tcx, M: Machine<'a, 'mir, 'tcx>> match err.kind { EvalErrorKind::InvalidNullPointerUsage => return validation_failure!("NULL reference", self.path), - EvalErrorKind::AlignmentCheckFailed { .. } => - return validation_failure!("unaligned reference", self.path), + EvalErrorKind::AlignmentCheckFailed { required, has } => + return validation_failure!(format!("unaligned reference \ + (required {} alignment but found {})", + required.bytes(), has.bytes()), self.path), _ => return validation_failure!( "dangling (out-of-bounds) reference (might be NULL at \ diff --git a/src/test/ui/consts/const-eval/ub-ref.rs b/src/test/ui/consts/const-eval/ub-ref.rs index 3b19f3b07753e..26dd2520a151f 100644 --- a/src/test/ui/consts/const-eval/ub-ref.rs +++ b/src/test/ui/consts/const-eval/ub-ref.rs @@ -5,6 +5,7 @@ use std::mem; const UNALIGNED: &u16 = unsafe { mem::transmute(&[0u8; 4]) }; //~^ ERROR it is undefined behavior to use this value +//~^^ type validation failed: encountered unaligned reference (required 2 alignment but found 1) const NULL: &u16 = unsafe { mem::transmute(0usize) }; //~^ ERROR it is undefined behavior to use this value diff --git a/src/test/ui/consts/const-eval/ub-ref.stderr b/src/test/ui/consts/const-eval/ub-ref.stderr index f8b5b2f50ce04..254561c81e192 100644 --- a/src/test/ui/consts/const-eval/ub-ref.stderr +++ b/src/test/ui/consts/const-eval/ub-ref.stderr @@ -2,12 +2,12 @@ error[E0080]: it is undefined behavior to use this value --> $DIR/ub-ref.rs:6:1 | LL | const UNALIGNED: &u16 = unsafe { mem::transmute(&[0u8; 4]) }; - | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ type validation failed: encountered unaligned reference + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ type validation failed: encountered unaligned reference (required 2 alignment but found 1) | = note: The rules on what exactly is undefined behavior aren't clear, so this check might be overzealous. Please open an issue on the rust compiler repository if you believe it should not be considered undefined behavior error[E0080]: it is undefined behavior to use this value - --> $DIR/ub-ref.rs:9:1 + --> $DIR/ub-ref.rs:10:1 | LL | const NULL: &u16 = unsafe { mem::transmute(0usize) }; | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ type validation failed: encountered 0, but expected something greater or equal to 1 @@ -15,7 +15,7 @@ LL | const NULL: &u16 = unsafe { mem::transmute(0usize) }; = note: The rules on what exactly is undefined behavior aren't clear, so this check might be overzealous. Please open an issue on the rust compiler repository if you believe it should not be considered undefined behavior error[E0080]: it is undefined behavior to use this value - --> $DIR/ub-ref.rs:12:1 + --> $DIR/ub-ref.rs:13:1 | LL | const REF_AS_USIZE: usize = unsafe { mem::transmute(&0) }; | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ type validation failed: encountered a pointer, but expected initialized plain (non-pointer) bytes @@ -23,7 +23,7 @@ LL | const REF_AS_USIZE: usize = unsafe { mem::transmute(&0) }; = note: The rules on what exactly is undefined behavior aren't clear, so this check might be overzealous. Please open an issue on the rust compiler repository if you believe it should not be considered undefined behavior error[E0080]: it is undefined behavior to use this value - --> $DIR/ub-ref.rs:15:1 + --> $DIR/ub-ref.rs:16:1 | LL | const REF_AS_USIZE_SLICE: &[usize] = &[unsafe { mem::transmute(&0) }]; | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ type validation failed: encountered a pointer at ., but expected plain (non-pointer) bytes @@ -31,7 +31,7 @@ LL | const REF_AS_USIZE_SLICE: &[usize] = &[unsafe { mem::transmute(&0) }]; = note: The rules on what exactly is undefined behavior aren't clear, so this check might be overzealous. Please open an issue on the rust compiler repository if you believe it should not be considered undefined behavior error[E0080]: it is undefined behavior to use this value - --> $DIR/ub-ref.rs:18:1 + --> $DIR/ub-ref.rs:19:1 | LL | const USIZE_AS_REF: &'static u8 = unsafe { mem::transmute(1337usize) }; | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ type validation failed: encountered integer pointer in non-ZST reference From 8ee1c0708a79f7c7234282f419122eeaba6419c7 Mon Sep 17 00:00:00 2001 From: Patrick McCarter Date: Fri, 22 Feb 2019 16:36:39 -0500 Subject: [PATCH 2/4] Change byte align message wording #58617 --- src/librustc_mir/interpret/validity.rs | 2 +- src/test/ui/consts/const-eval/ub-ref.rs | 2 +- src/test/ui/consts/const-eval/ub-ref.stderr | 2 +- 3 files changed, 3 insertions(+), 3 deletions(-) diff --git a/src/librustc_mir/interpret/validity.rs b/src/librustc_mir/interpret/validity.rs index 91a43d5c991bf..6b932b17524c9 100644 --- a/src/librustc_mir/interpret/validity.rs +++ b/src/librustc_mir/interpret/validity.rs @@ -359,7 +359,7 @@ impl<'rt, 'a, 'mir, 'tcx, M: Machine<'a, 'mir, 'tcx>> return validation_failure!("NULL reference", self.path), EvalErrorKind::AlignmentCheckFailed { required, has } => return validation_failure!(format!("unaligned reference \ - (required {} alignment but found {})", + (required {} byte alignment but found {})", required.bytes(), has.bytes()), self.path), _ => return validation_failure!( diff --git a/src/test/ui/consts/const-eval/ub-ref.rs b/src/test/ui/consts/const-eval/ub-ref.rs index 26dd2520a151f..c1e2b095ad1ba 100644 --- a/src/test/ui/consts/const-eval/ub-ref.rs +++ b/src/test/ui/consts/const-eval/ub-ref.rs @@ -5,7 +5,7 @@ use std::mem; const UNALIGNED: &u16 = unsafe { mem::transmute(&[0u8; 4]) }; //~^ ERROR it is undefined behavior to use this value -//~^^ type validation failed: encountered unaligned reference (required 2 alignment but found 1) +//~^^ type validation failed: encountered unaligned reference (required 2 byte alignment but found 1) const NULL: &u16 = unsafe { mem::transmute(0usize) }; //~^ ERROR it is undefined behavior to use this value diff --git a/src/test/ui/consts/const-eval/ub-ref.stderr b/src/test/ui/consts/const-eval/ub-ref.stderr index 254561c81e192..371467a5d1e95 100644 --- a/src/test/ui/consts/const-eval/ub-ref.stderr +++ b/src/test/ui/consts/const-eval/ub-ref.stderr @@ -2,7 +2,7 @@ error[E0080]: it is undefined behavior to use this value --> $DIR/ub-ref.rs:6:1 | LL | const UNALIGNED: &u16 = unsafe { mem::transmute(&[0u8; 4]) }; - | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ type validation failed: encountered unaligned reference (required 2 alignment but found 1) + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ type validation failed: encountered unaligned reference (required 2 byte alignment but found 1) | = note: The rules on what exactly is undefined behavior aren't clear, so this check might be overzealous. Please open an issue on the rust compiler repository if you believe it should not be considered undefined behavior From 5952c610a7e2d39adf956bd543b1c07d6791b7f9 Mon Sep 17 00:00:00 2001 From: Patrick McCarter Date: Fri, 22 Feb 2019 17:07:13 -0500 Subject: [PATCH 3/4] tidy line length override #58617 --- src/test/ui/consts/const-eval/ub-ref.rs | 1 + 1 file changed, 1 insertion(+) diff --git a/src/test/ui/consts/const-eval/ub-ref.rs b/src/test/ui/consts/const-eval/ub-ref.rs index c1e2b095ad1ba..0d8f30159b316 100644 --- a/src/test/ui/consts/const-eval/ub-ref.rs +++ b/src/test/ui/consts/const-eval/ub-ref.rs @@ -1,3 +1,4 @@ +// ignore-tidy-linelength #![feature(const_transmute)] #![allow(const_err)] // make sure we cannot allow away the errors tested here From d0c110f2c6a82f3c1cd6ebd004d211a43978b7d1 Mon Sep 17 00:00:00 2001 From: Patrick McCarter Date: Fri, 22 Feb 2019 19:23:03 -0500 Subject: [PATCH 4/4] #58658 bless after line split for tidy --- src/test/ui/consts/const-eval/ub-ref.stderr | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/src/test/ui/consts/const-eval/ub-ref.stderr b/src/test/ui/consts/const-eval/ub-ref.stderr index 371467a5d1e95..33535c235e3a3 100644 --- a/src/test/ui/consts/const-eval/ub-ref.stderr +++ b/src/test/ui/consts/const-eval/ub-ref.stderr @@ -1,5 +1,5 @@ error[E0080]: it is undefined behavior to use this value - --> $DIR/ub-ref.rs:6:1 + --> $DIR/ub-ref.rs:7:1 | LL | const UNALIGNED: &u16 = unsafe { mem::transmute(&[0u8; 4]) }; | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ type validation failed: encountered unaligned reference (required 2 byte alignment but found 1) @@ -7,7 +7,7 @@ LL | const UNALIGNED: &u16 = unsafe { mem::transmute(&[0u8; 4]) }; = note: The rules on what exactly is undefined behavior aren't clear, so this check might be overzealous. Please open an issue on the rust compiler repository if you believe it should not be considered undefined behavior error[E0080]: it is undefined behavior to use this value - --> $DIR/ub-ref.rs:10:1 + --> $DIR/ub-ref.rs:11:1 | LL | const NULL: &u16 = unsafe { mem::transmute(0usize) }; | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ type validation failed: encountered 0, but expected something greater or equal to 1 @@ -15,7 +15,7 @@ LL | const NULL: &u16 = unsafe { mem::transmute(0usize) }; = note: The rules on what exactly is undefined behavior aren't clear, so this check might be overzealous. Please open an issue on the rust compiler repository if you believe it should not be considered undefined behavior error[E0080]: it is undefined behavior to use this value - --> $DIR/ub-ref.rs:13:1 + --> $DIR/ub-ref.rs:14:1 | LL | const REF_AS_USIZE: usize = unsafe { mem::transmute(&0) }; | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ type validation failed: encountered a pointer, but expected initialized plain (non-pointer) bytes @@ -23,7 +23,7 @@ LL | const REF_AS_USIZE: usize = unsafe { mem::transmute(&0) }; = note: The rules on what exactly is undefined behavior aren't clear, so this check might be overzealous. Please open an issue on the rust compiler repository if you believe it should not be considered undefined behavior error[E0080]: it is undefined behavior to use this value - --> $DIR/ub-ref.rs:16:1 + --> $DIR/ub-ref.rs:17:1 | LL | const REF_AS_USIZE_SLICE: &[usize] = &[unsafe { mem::transmute(&0) }]; | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ type validation failed: encountered a pointer at ., but expected plain (non-pointer) bytes @@ -31,7 +31,7 @@ LL | const REF_AS_USIZE_SLICE: &[usize] = &[unsafe { mem::transmute(&0) }]; = note: The rules on what exactly is undefined behavior aren't clear, so this check might be overzealous. Please open an issue on the rust compiler repository if you believe it should not be considered undefined behavior error[E0080]: it is undefined behavior to use this value - --> $DIR/ub-ref.rs:19:1 + --> $DIR/ub-ref.rs:20:1 | LL | const USIZE_AS_REF: &'static u8 = unsafe { mem::transmute(1337usize) }; | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ type validation failed: encountered integer pointer in non-ZST reference