Show the values and computation that would overflow a const evaluation or propagation #73513

oli-obk · 2020-06-19T17:21:45Z

In contrast to the example in the issue it doesn't use individual spans for each operand. The effort required to implement that is quite high compared to the little (if at all) benefit it would bring to diagnostics.

cc @shepmaster

The way this is implemented it is also fairly easy to do the same for overflow panics at runtime, but that should be done in a separate PR since it may have runtime performance implications.

rust-highfive · 2020-06-19T17:21:48Z

r? @estebank

(rust_highfive has picked a reviewer for you, use r? to override)

estebank · 2020-06-19T18:06:33Z

r=me on the changes with green CI

I have one nitpick to change the output slightly, but I'm not blocking this PR on it:

error: this arithmetic operation will overflow
  --> $DIR/const-err2.rs:19:13
   |
LL |     let a = -std::i8::MIN;
   |             ^^^^^^^^^^^^^ attempt to negate `-128` would be greater than `i8::MAX`
   |
   = note: `#[deny(arithmetic_overflow)]` on by default

or some other wording that mentions the type.

rust-highfive · 2020-06-19T18:27:29Z

The job x86_64-gnu-llvm-8 of your PR failed (pretty log, raw log). Through arcane magic we have determined that the following fragments from the build log may contain information about the problem.

Click to expand the log.

##[section]Starting: Linux x86_64-gnu-llvm-8
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Agent name: 'Azure Pipelines 2'
Agent machine name: 'fv-az578'
Current agent version: '2.170.1'
##[group]Operating System
16.04.6
LTS
LTS
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Environment: ubuntu-16.04
Version: 20200614.1
Included Software: https://github.com/actions/virtual-environments/blob/ubuntu16/20200614.1/images/linux/Ubuntu1604-README.md
##[endgroup]
Agent running as: 'vsts'
Prepare build directory.
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Downloading task: Bash (3.163.3)
Checking job knob settings.
   Knob: AgentToolsDirectory = /opt/hostedtoolcache Source: ${AGENT_TOOLSDIRECTORY} 
   Knob: AgentPerflog = /home/vsts/perflog Source: ${VSTS_AGENT_PERFLOG} 
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---
========================== Starting Command Output ===========================
[command]/bin/bash --noprofile --norc /home/vsts/work/_temp/380b736d-29f3-4d24-8e3c-db27483ffc14.sh

##[section]Finishing: Disable git automatic line ending conversion
##[section]Starting: Checkout rust-lang/rust@refs/pull/73513/merge to s
Task         : Get sources
Description  : Get sources from a repository. Supports Git, TfsVC, and SVN repositories.
Version      : 1.0.0
Author       : Microsoft
---
##[command]git remote add origin https://github.com/rust-lang/rust
##[command]git config gc.auto 0
##[command]git config --get-all http.https://github.com/rust-lang/rust.extraheader
##[command]git config --get-all http.proxy
##[command]git -c http.extraheader="AUTHORIZATION: basic ***" fetch --force --tags --prune --progress --no-recurse-submodules --depth=2 origin +refs/heads/*:refs/remotes/origin/* +refs/pull/73513/merge:refs/remotes/pull/73513/merge
---
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Step 5/8 : ENV RUST_CONFIGURE_ARGS       --build=x86_64-unknown-linux-gnu       --llvm-root=/usr/lib/llvm-8       --enable-llvm-link-shared       --set rust.thin-lto-import-instr-limit=10
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Step 6/8 : ENV SCRIPT python2.7 ../x.py test --exclude src/tools/tidy &&            python2.7 ../x.py test src/test/mir-opt --pass=build                                   --target=armv5te-unknown-linux-gnueabi &&            python2.7 ../x.py test src/tools/tidy
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Step 7/8 : ENV NO_DEBUG_ASSERTIONS=1
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---
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failures:

---- [mir-opt] mir-opt/const_prop/bad_op_div_by_zero.rs stdout ----
46 +                                          // + span: $DIR/bad_op_div_by_zero.rs:5:14: 5:19
47 +                                          // + literal: Const { ty: bool, val: Value(Scalar(0x01)) }
48           assert(!move _4, "attempt to divide by zero") -> bb1; // scope 1 at $DIR/bad_op_div_by_zero.rs:5:14: 5:19
+                                            // ty::Const
+                                            // + ty: i32
+                                            // + val: Value(Scalar(0x00000001))
+                                            // mir::Constant
+                                            // + span: $DIR/bad_op_div_by_zero.rs:5:14: 5:15
+                                            // + literal: Const { ty: i32, val: Value(Scalar(0x00000001)) }
50   
51       bb1: {

91 +                                          // mir::Constant
91 +                                          // mir::Constant
92 +                                          // + span: $DIR/bad_op_div_by_zero.rs:5:14: 5:19
93 +                                          // + literal: Const { ty: bool, val: Value(Scalar(0x00)) }
+                                            // ty::Const
+                                            // + ty: i32
+                                            // + val: Value(Scalar(0x00000001))
+                                            // mir::Constant
+                                            // + span: $DIR/bad_op_div_by_zero.rs:5:14: 5:15
+                                            // + literal: Const { ty: i32, val: Value(Scalar(0x00000001)) }
95   
96       bb2: {


thread '[mir-opt] mir-opt/const_prop/bad_op_div_by_zero.rs' panicked at 'Actual MIR output differs from expected MIR output /checkout/src/test/mir-opt/const_prop/bad_op_div_by_zero/rustc.main.ConstProp.diff', src/tools/compiletest/src/runtest.rs:3194:25


---- [mir-opt] mir-opt/const_prop/bad_op_mod_by_zero.rs stdout ----
46 +                                          // + span: $DIR/bad_op_mod_by_zero.rs:5:14: 5:19
47 +                                          // + literal: Const { ty: bool, val: Value(Scalar(0x01)) }
48           assert(!move _4, "attempt to calculate the remainder with a divisor of zero") -> bb1; // scope 1 at $DIR/bad_op_mod_by_zero.rs:5:14: 5:19
+                                            // ty::Const
+                                            // + ty: i32
+                                            // + val: Value(Scalar(0x00000001))
+                                            // mir::Constant
+                                            // + span: $DIR/bad_op_mod_by_zero.rs:5:14: 5:15
+                                            // + literal: Const { ty: i32, val: Value(Scalar(0x00000001)) }
50   
51       bb1: {

91 +                                          // mir::Constant
91 +                                          // mir::Constant
92 +                                          // + span: $DIR/bad_op_mod_by_zero.rs:5:14: 5:19
93 +                                          // + literal: Const { ty: bool, val: Value(Scalar(0x00)) }
+                                            // ty::Const
+                                            // + ty: i32
+                                            // + val: Value(Scalar(0x00000001))
+                                            // mir::Constant
+                                            // + span: $DIR/bad_op_mod_by_zero.rs:5:14: 5:15
+                                            // + literal: Const { ty: i32, val: Value(Scalar(0x00000001)) }
95   
96       bb2: {


thread '[mir-opt] mir-opt/const_prop/bad_op_mod_by_zero.rs' panicked at 'Actual MIR output differs from expected MIR output /checkout/src/test/mir-opt/const_prop/bad_op_mod_by_zero/rustc.main.ConstProp.diff', src/tools/compiletest/src/runtest.rs:3194:25
---- [mir-opt] mir-opt/const_prop/checked_add.rs stdout ----
---- [mir-opt] mir-opt/const_prop/checked_add.rs stdout ----
34 +                                          // + span: $DIR/checked_add.rs:5:18: 5:23
35 +                                          // + literal: Const { ty: bool, val: Value(Scalar(0x00)) }
36 +         assert(!const false, "attempt to add with overflow") -> bb1; // scope 0 at $DIR/checked_add.rs:5:18: 5:23
- +                                          // ty::Const
+                                            // ty::Const
38 +                                          // + ty: bool
39 +                                          // + val: Value(Scalar(0x00))


41 +                                          // + span: $DIR/checked_add.rs:5:18: 5:23
42 +                                          // + literal: Const { ty: bool, val: Value(Scalar(0x00)) }
+ +                                          // ty::Const
+                                            // + ty: u32
+                                            // + val: Value(Scalar(0x00000001))
+                                            // mir::Constant
+                                            // + span: $DIR/checked_add.rs:5:18: 5:19
+                                            // + literal: Const { ty: u32, val: Value(Scalar(0x00000001)) }
+                                            // ty::Const
+                                            // + ty: u32
+                                            // + val: Value(Scalar(0x00000001))
+                                            // mir::Constant
+                                            // + span: $DIR/checked_add.rs:5:22: 5:23
+                                            // + literal: Const { ty: u32, val: Value(Scalar(0x00000001)) }
44   
45       bb1: {


thread '[mir-opt] mir-opt/const_prop/checked_add.rs' panicked at 'Actual MIR output differs from expected MIR output /checkout/src/test/mir-opt/const_prop/checked_add/rustc.main.ConstProp.diff', src/tools/compiletest/src/runtest.rs:3194:25
---- [mir-opt] mir-opt/const_prop/indirect.rs stdout ----
23                                            // mir::Constant
23                                            // mir::Constant
24 -                                          // + span: $DIR/indirect.rs:5:14: 5:18
25 -                                          // + literal: Const { ty: u32, val: Value(Scalar(0x00000002)) }
- -         _3 = CheckedAdd(move _2, const 1u8); // scope 0 at $DIR/indirect.rs:5:13: 5:29
+ -         _3 = CheckedAdd(_2, const 1u8);  // scope 0 at $DIR/indirect.rs:5:13: 5:29
27 +                                          // + span: $DIR/indirect.rs:5:13: 5:25
28 +                                          // + literal: Const { ty: u8, val: Value(Scalar(0x02)) }
29 +         _3 = (const 3u8, const false);   // scope 0 at $DIR/indirect.rs:5:13: 5:29

37 -         assert(!move (_3.1: bool), "attempt to add with overflow") -> bb1; // scope 0 at $DIR/indirect.rs:5:13: 5:29
38 +                                          // + span: $DIR/indirect.rs:5:13: 5:29
39 +                                          // + literal: Const { ty: u8, val: Value(Scalar(0x03)) }
- +                                          // ty::Const
+                                            // ty::Const
41 +                                          // + ty: bool
42 +                                          // + val: Value(Scalar(0x00))

50 +                                          // mir::Constant
50 +                                          // mir::Constant
51 +                                          // + span: $DIR/indirect.rs:5:13: 5:29
52 +                                          // + literal: Const { ty: bool, val: Value(Scalar(0x00)) }
+ +                                          // ty::Const
+                                            // + ty: u8
+                                            // + val: Value(Scalar(0x01))
+                                            // mir::Constant
+                                            // + span: $DIR/indirect.rs:5:28: 5:29
+                                            // + literal: Const { ty: u8, val: Value(Scalar(0x01)) }
54   
55       bb1: {


thread '[mir-opt] mir-opt/const_prop/indirect.rs' panicked at 'Actual MIR output differs from expected MIR output /checkout/src/test/mir-opt/const_prop/indirect/rustc.main.ConstProp.diff', src/tools/compiletest/src/runtest.rs:3194:25
---- [mir-opt] mir-opt/const_prop/optimizes_into_variable.rs stdout ----
---- [mir-opt] mir-opt/const_prop/optimizes_into_variable.rs stdout ----
47 +                                          // + span: $DIR/optimizes_into_variable.rs:12:13: 12:18
48 +                                          // + literal: Const { ty: bool, val: Value(Scalar(0x00)) }
49 +         assert(!const false, "attempt to add with overflow") -> bb1; // scope 0 at $DIR/optimizes_into_variable.rs:12:13: 12:18
- +                                          // ty::Const
+                                            // ty::Const
51 +                                          // + ty: bool
52 +                                          // + val: Value(Scalar(0x00))


54 +                                          // + span: $DIR/optimizes_into_variable.rs:12:13: 12:18
55 +                                          // + literal: Const { ty: bool, val: Value(Scalar(0x00)) }
+ +                                          // ty::Const
+                                            // + ty: i32
+                                            // + val: Value(Scalar(0x00000002))
+                                            // mir::Constant
+                                            // + span: $DIR/optimizes_into_variable.rs:12:13: 12:14
+                                            // + literal: Const { ty: i32, val: Value(Scalar(0x00000002)) }
+                                            // ty::Const
+                                            // + ty: i32
+                                            // + val: Value(Scalar(0x00000002))
+                                            // mir::Constant
+                                            // + span: $DIR/optimizes_into_variable.rs:12:17: 12:18
+                                            // + literal: Const { ty: i32, val: Value(Scalar(0x00000002)) }
57   
58       bb1: {


thread '[mir-opt] mir-opt/const_prop/optimizes_into_variable.rs' panicked at 'Actual MIR output differs from expected MIR output /checkout/src/test/mir-opt/const_prop/optimizes_into_variable/64bit/rustc.main.ConstProp.diff', src/tools/compiletest/src/runtest.rs:3194:25
---- [mir-opt] mir-opt/const_prop/return_place.rs stdout ----
---- [mir-opt] mir-opt/const_prop/return_place.rs stdout ----
29 +                                          // + span: $DIR/return_place.rs:6:5: 6:10
30 +                                          // + literal: Const { ty: bool, val: Value(Scalar(0x00)) }
31 +         assert(!const false, "attempt to add with overflow") -> bb1; // scope 0 at $DIR/return_place.rs:6:5: 6:10
- +                                          // ty::Const
+                                            // ty::Const
33 +                                          // + ty: bool
34 +                                          // + val: Value(Scalar(0x00))


36 +                                          // + span: $DIR/return_place.rs:6:5: 6:10
37 +                                          // + literal: Const { ty: bool, val: Value(Scalar(0x00)) }
+ +                                          // ty::Const
+                                            // + ty: u32
+                                            // + val: Value(Scalar(0x00000002))
+                                            // mir::Constant
+                                            // + span: $DIR/return_place.rs:6:5: 6:6
+                                            // + literal: Const { ty: u32, val: Value(Scalar(0x00000002)) }
+                                            // ty::Const
+                                            // + ty: u32
+                                            // + val: Value(Scalar(0x00000002))
+                                            // mir::Constant
+                                            // + span: $DIR/return_place.rs:6:9: 6:10
+                                            // + literal: Const { ty: u32, val: Value(Scalar(0x00000002)) }
39   
40       bb1: {


thread '[mir-opt] mir-opt/const_prop/return_place.rs' panicked at 'Actual MIR output differs from expected MIR output /checkout/src/test/mir-opt/const_prop/return_place/rustc.add.ConstProp.diff', src/tools/compiletest/src/runtest.rs:3194:25
---- [mir-opt] mir-opt/issue-41697.rs stdout ----
---- [mir-opt] mir-opt/issue-41697.rs stdout ----
19                                          // + span: $DIR/issue-41697.rs:18:21: 18:22
20                                          // + literal: Const { ty: usize, val: Value(Scalar(0x0000000000000001)) }
21         assert(!move (_1.1: bool), "attempt to add with overflow") -> [success: bb2, unwind: bb1]; // scope 0 at $DIR/issue-41697.rs:18:19: 18:22
+                                          // ty::Const
+                                          // + ty: usize
+                                          // + val: Value(Scalar(0x0000000000000001))
+                                          // mir::Constant
+                                          // + span: $DIR/issue-41697.rs:18:19: 18:20
+                                          // + literal: Const { ty: usize, val: Value(Scalar(0x0000000000000001)) }
+                                          // ty::Const
+                                          // + ty: usize
+                                          // + val: Value(Scalar(0x0000000000000001))
+                                          // mir::Constant
+                                          // + span: $DIR/issue-41697.rs:18:21: 18:22
+                                          // + literal: Const { ty: usize, val: Value(Scalar(0x0000000000000001)) }
23 
23 
24     bb1 (cleanup): {

thread '[mir-opt] mir-opt/issue-41697.rs' panicked at 'Actual MIR output differs from expected MIR output /checkout/src/test/mir-opt/issue-41697/64bit/rustc.{{impl}}-{{constant}}.SimplifyCfg-qualify-consts.after.mir', src/tools/compiletest/src/runtest.rs:3194:25

failures:
    [mir-opt] mir-opt/const_prop/bad_op_div_by_zero.rs
    [mir-opt] mir-opt/const_prop/bad_op_mod_by_zero.rs
---

thread 'main' panicked at 'Some tests failed', src/tools/compiletest/src/main.rs:348:22


command did not execute successfully: "/checkout/obj/build/x86_64-unknown-linux-gnu/stage0-tools-bin/compiletest" "--compile-lib-path" "/checkout/obj/build/x86_64-unknown-linux-gnu/stage2/lib" "--run-lib-path" "/checkout/obj/build/x86_64-unknown-linux-gnu/stage2/lib/rustlib/x86_64-unknown-linux-gnu/lib" "--rustc-path" "/checkout/obj/build/x86_64-unknown-linux-gnu/stage2/bin/rustc" "--src-base" "/checkout/src/test/mir-opt" "--build-base" "/checkout/obj/build/x86_64-unknown-linux-gnu/test/mir-opt" "--stage-id" "stage2-x86_64-unknown-linux-gnu" "--mode" "mir-opt" "--target" "x86_64-unknown-linux-gnu" "--host" "x86_64-unknown-linux-gnu" "--llvm-filecheck" "/usr/lib/llvm-8/bin/FileCheck" "--nodejs" "/usr/bin/node" "--host-rustcflags" "-Crpath -O -Cdebuginfo=0 -Zunstable-options  -Lnative=/checkout/obj/build/x86_64-unknown-linux-gnu/native/rust-test-helpers" "--target-rustcflags" "-Crpath -O -Cdebuginfo=0 -Zunstable-options  -Lnative=/checkout/obj/build/x86_64-unknown-linux-gnu/native/rust-test-helpers" "--docck-python" "/usr/bin/python2.7" "--lldb-python" "/usr/bin/python2.7" "--gdb" "/usr/bin/gdb" "--quiet" "--llvm-version" "8.0.0" "--system-llvm" "--cc" "" "--cxx" "" "--cflags" "" "--llvm-components" "" "--adb-path" "adb" "--adb-test-dir" "/data/tmp/work" "--android-cross-path" "" "--color" "always"


failed to run: /checkout/obj/build/bootstrap/debug/bootstrap test --exclude src/tools/tidy
Build completed unsuccessfully in 1:01:00
Build completed unsuccessfully in 1:01:00
== clock drift check ==
  local time: Fri Jun 19 18:27:11 UTC 2020
  network time: Fri, 19 Jun 2020 18:27:11 GMT
== end clock drift check ==

##[error]Bash exited with code '1'.
##[section]Finishing: Run build
##[section]Starting: Checkout rust-lang/rust@refs/pull/73513/merge to s
Task         : Get sources
Description  : Get sources from a repository. Supports Git, TfsVC, and SVN repositories.
Version      : 1.0.0
Author       : Microsoft
Author       : Microsoft
Help         : [More Information](https://go.microsoft.com/fwlink/?LinkId=798199)
==============================================================================
Cleaning any cached credential from repository: rust-lang/rust (GitHub)
##[section]Finishing: Checkout rust-lang/rust@refs/pull/73513/merge to s
Cleaning up task key
Start cleaning up orphan processes.
Terminate orphan process: pid (3577) (python)
##[section]Finishing: Finalize Job

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oli-obk · 2020-06-20T10:12:31Z

or some other wording that mentions the type.

Unfortunately we don't have the type available at that time. I could probably get ConstInt to emit a type so you'd have -128_i8 instead of just -128

oli-obk · 2020-06-20T10:13:39Z

cc @RalfJung this touches a little bit of miri-engine error handling

oli-obk · 2020-06-20T10:30:47Z

@bors try @rust-timer queue

rust-timer · 2020-06-20T10:30:48Z

Awaiting bors try build completion

bors · 2020-06-20T10:30:59Z

⌛ Trying commit a1b92b4456b18789a1d8decfd9136a752c811a1a with merge 54b2e11bab628c62703dc119d93e1807bba5e4c7...

src/test/mir-opt/const_prop/bad_op_div_by_zero/rustc.main.ConstProp.diff

RalfJung · 2020-06-20T11:11:48Z

src/test/ui/associated-const/issue-69020-assoc-const-arith-overflow.noopt.stderr


 error: this arithmetic operation will overflow
  --> $DIR/issue-69020-assoc-const-arith-overflow.rs:34:22
   |
 LL |     const ADD: i32 = (i32::MAX+1) + T::ADD;
-   |                      ^^^^^^^^^^^^ attempt to add with overflow
+   |                      ^^^^^^^^^^^^ attempt to compute `2147483647 + 1` which would overflow


So computations are enclosed in ` but constants are not? Are we doing that consistently?

src/librustc_middle/mir/interpret/int.rs

RalfJung · 2020-06-20T12:42:31Z

src/librustc_middle/ty/int.rs

+                        (2, _) => write!(fmt, "_u16")?,
+                        (4, _) => write!(fmt, "_u32")?,
+                        (8, _) => write!(fmt, "_u64")?,
+                        (16, _) => write!(fmt, "_u128")?,


Why the _? Is there precedent for that?

I was under the impression that that's the proper way to do this. I think clippy also suggests everything with an underscore

No strong opinion, I just don't think I have seen this before.

Are we emitting any other diagnostics in rustc like this? I haven't seen any either, but I could be out of touch.

I haven't checked

RalfJung · 2020-06-20T12:45:45Z

src/librustc_middle/ty/int.rs

@@ -0,0 +1,111 @@
+use crate::mir::interpret::truncate;
+use rustc_target::abi::Size;


Now this file is even more removed from ConstValue, which it seems closely related to.^^

Maybe call this ty/const.rs, with the plan to move ConstValue here as part of #72396?

const isn't possible, but consts.

oli-obk · 2020-06-20T14:53:02Z

Heh, the PR already bitrotted. I rebased and sqashed the commits

bors · 2020-06-21T09:46:21Z

☔ The latest upstream changes (presumably #71911) made this pull request unmergeable. Please resolve the merge conflicts.

oli-obk · 2020-06-21T13:22:40Z

@estebank there were significant changes to the test output, can you have another look to see if you're still ok with this?

estebank · 2020-06-21T17:57:21Z

Only nitpicks would ve that we always say overflow even when it underflows and that we could potentially recommend changing types, but these things are very minor and shouldn't block this pr. I worry slightly that overflow is jargon that we never introduce, which is why I suggested the wordier labels before, but at the same time it is very common wording for people coming from other langs. None of these things needs to be addressed now.

RalfJung · 2020-06-21T18:13:13Z

(FWIW I feel like "underflow" is much stranger jargon than "overflow". I'd call it "overflow" even when it's wrapping around negatively. But maybe I'm the odd one out there.)

oli-obk · 2020-06-25T15:02:31Z

@bors r=estebank

bors · 2020-06-25T15:02:32Z

📌 Commit 78b549f6607be49c6b6a49c3a2465a9756bf56f7 has been approved by estebank

bors · 2020-06-25T16:28:53Z

⌛ Testing commit 78b549f6607be49c6b6a49c3a2465a9756bf56f7 with merge f7a7b6b77c6f06c2d97eed7b96e34156a753505b...

bors · 2020-06-25T17:36:55Z

💔 Test failed - checks-azure

…n or propagation

oli-obk · 2020-06-26T08:09:24Z

@bors r=estebank

bors · 2020-06-26T08:09:25Z

📌 Commit 819cde5 has been approved by estebank

bors · 2020-06-26T14:08:52Z

⌛ Testing commit 819cde5 with merge 7750c3d...

bors · 2020-06-26T18:23:06Z

☀️ Test successful - checks-azure
Approved by: estebank
Pushing 7750c3d to master...

rust-highfive · 2020-06-26T18:24:28Z

📣 Toolstate changed by #73513!

Tested on commit 7750c3d.
Direct link to PR: #73513

💔 miri on windows: test-pass → test-fail (cc @oli-obk @eddyb @RalfJung).
💔 miri on linux: test-pass → test-fail (cc @oli-obk @eddyb @RalfJung).

@oli-obk

Tested on commit rust-lang/rust@7750c3d. Direct link to PR: <rust-lang/rust#73513> 💔 miri on windows: test-pass → test-fail (cc @oli-obk @eddyb @RalfJung). 💔 miri on linux: test-pass → test-fail (cc @oli-obk @eddyb @RalfJung).

rust-highfive assigned estebank Jun 19, 2020

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Perform validation in const_eval_raw, return valtree from const_eval and decouple MIR-embedded consts from the rest #72396

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oli-obk force-pushed the const_binop_overflow branch from 3b47280 to 9ed651f Compare June 25, 2020 13:48

bors added S-waiting-on-bors Status: Waiting on bors to run and complete tests. Bors will change the label on completion. and removed S-waiting-on-author Status: This is awaiting some action (such as code changes or more information) from the author. labels Jun 25, 2020

oli-obk mentioned this pull request Jun 25, 2020

split up rustc_middle/mir/mod.rs #73723

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bors added S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. and removed S-waiting-on-bors Status: Waiting on bors to run and complete tests. Bors will change the label on completion. labels Jun 25, 2020

Show the values and computation that would overflow a const evaluatio…

819cde5

…n or propagation

oli-obk force-pushed the const_binop_overflow branch from 78b549f to 819cde5 Compare June 26, 2020 08:09

bors added S-waiting-on-bors Status: Waiting on bors to run and complete tests. Bors will change the label on completion. and removed S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. labels Jun 26, 2020

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miri no longer builds after rust-lang/rust#73513 #73773

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This was referenced Jun 26, 2020

Implement a generic Destination Propagation optimization on MIR #72632

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add spans to injected coverage counters, extract with CoverageData query #73684

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oli-obk deleted the const_binop_overflow branch June 26, 2020 18:42

JohnTitor mentioned this pull request Jul 3, 2020

1.46.0-nightly panics on a particular proc macro invocation #73993

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cuviper added this to the 1.46 milestone May 2, 2024

		@@ -0,0 +1,111 @@
		use crate::mir::interpret::truncate;
		use rustc_target::abi::Size;

Show the values and computation that would overflow a const evaluation or propagation #73513

Show the values and computation that would overflow a const evaluation or propagation #73513

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