Add diagnostic for stack allocations of 1 GB or more

[iSwapna]

Add diagnostic for stack allocations of 1 GB or more

Zulip conversation [here](Issue 83060 - Regression with large stack arrays (2-4GB))

Do I generate an ICE or issue a warning?

cc #83060

[rustbot]

r? @wesleywiser

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[iSwapna]

I have addressed all the comments, but not sure how to add the stdout file for 32 bit :
Testing stage2 compiletest suite=ui mode=ui (x86_64-unknown-linux-gnu -> i686-unknown-linux-gnu)
fails in CI:

failures:

  ---- [ui] tests/ui/codegen/issue-83060-large-stack-size.rs stdout ----
  diff of stderr:

  - warning: Dangerous stack allocation of size: 1 GiB exceeds most architecture limits
  -
  - warning: 1 warning emitted
  -
  -

[iSwapna]

@rustbot review

[iSwapna]

I have addressed all the comments, but not sure how to add the stdout file for 32 bit : Testing stage2 compiletest suite=ui mode=ui (x86_64-unknown-linux-gnu -> i686-unknown-linux-gnu) fails in CI:

failures:

  ---- [ui] tests/ui/codegen/issue-83060-large-stack-size.rs stdout ----
  diff of stderr:

  - warning: Dangerous stack allocation of size: 1 GiB exceeds most architecture limits
  -
  - warning: 1 warning emitted
  -
  -

[Dylan-DPC]

@iSwapna any updates on this? thanks

[iSwapna]

@iSwapna any updates on this? thanks

Sorry, I am taking a class @Stanford CS103, taking every bit of my time outside of work. That's towards wanting a good grounding on CS/compilers as well, to do a better job here!

There was a CI failure (fluent related) which I have not got an answer on how to address, the Zulip discussion is here: Issue 83060 - Regression with large stack arrays (2-4GB)

If I could get an answer on how to address the CI issue, I can take care of this in a couple of weeks (after impending midterm)

[Dylan-DPC]

Sure, Thanks for the update. Just wanted to know if you are still working on it and have any updates. You should get a reply on zulip else you can bump it i guess

[iSwapna]

Sure, Thanks for the update. Just wanted to know if you are still working on it and have any updates. You should get a reply on zulip else you can bump it i guess

will do! Thank you for checking!

[rust-log-analyzer]

The job x86_64-gnu-llvm-18 failed! Check out the build log: (web) (plain)

Click to see the possible cause of the failure (guessed by this bot)

#17 exporting to docker image format
#17 sending tarball 27.9s done
#17 DONE 33.2s
##[endgroup]
Setting extra environment values for docker:  --env ENABLE_GCC_CODEGEN=1 --env GCC_EXEC_PREFIX=/usr/lib/gcc/
[CI_JOB_NAME=x86_64-gnu-llvm-18]
debug: `DISABLE_CI_RUSTC_IF_INCOMPATIBLE` configured.
---
sccache: Starting the server...
##[group]Configure the build
configure: processing command line
configure: 
configure: build.configure-args := ['--build=x86_64-unknown-linux-gnu', '--llvm-root=/usr/lib/llvm-18', '--enable-llvm-link-shared', '--set', 'rust.randomize-layout=true', '--set', 'rust.thin-lto-import-instr-limit=10', '--enable-verbose-configure', '--enable-sccache', '--disable-manage-submodules', '--enable-locked-deps', '--enable-cargo-native-static', '--set', 'rust.codegen-units-std=1', '--set', 'dist.compression-profile=balanced', '--dist-compression-formats=xz', '--set', 'rust.lld=false', '--disable-dist-src', '--release-channel=nightly', '--enable-debug-assertions', '--enable-overflow-checks', '--enable-llvm-assertions', '--set', 'rust.verify-llvm-ir', '--set', 'rust.codegen-backends=llvm,cranelift,gcc', '--set', 'llvm.static-libstdcpp', '--enable-new-symbol-mangling']
configure: target.x86_64-unknown-linux-gnu.llvm-config := /usr/lib/llvm-18/bin/llvm-config
configure: llvm.link-shared     := True
configure: rust.randomize-layout := True
configure: rust.thin-lto-import-instr-limit := 10
---
  Downloaded boml v0.3.1
   Compiling boml v0.3.1
   Compiling y v0.1.0 (/checkout/compiler/rustc_codegen_gcc/build_system)
    Finished `release` profile [optimized] target(s) in 3.80s
     Running `/checkout/obj/build/x86_64-unknown-linux-gnu/stage1-codegen/x86_64-unknown-linux-gnu/release/y test --use-system-gcc --use-backend gcc --out-dir /checkout/obj/build/x86_64-unknown-linux-gnu/stage1-tools/cg_gcc --release --mini-tests --std-tests`
Using system GCC
[BUILD] example
[AOT] mini_core_hello_world
/checkout/obj/build/x86_64-unknown-linux-gnu/stage1-tools/cg_gcc/mini_core_hello_world
abc
---
---- compiler/rustc_lint_defs/src/builtin.rs - builtin::DANGEROUS_STACK_ALLOCATION (line 720) stdout ----
warning: allocation of size: 1 GiB  exceeds most system architecture limits
 --> compiler/rustc_lint_defs/src/builtin.rs:723:9
  |
4 |     let mut x: [u8; CAP>>1] = [0; CAP>>1];
  |
  = note: `#[warn(dangerous_stack_allocation)]` on by default

warning: 1 warning emitted
warning: 1 warning emitted

Test executable failed (signal: 6 (SIGABRT) (core dumped)).
stderr:

thread '<unknown>' has overflowed its stack
fatal runtime error: stack overflow
---
    compiler/rustc_lint_defs/src/builtin.rs - builtin::DANGEROUS_STACK_ALLOCATION (line 720)

test result: FAILED. 118 passed; 1 failed; 25 ignored; 0 measured; 0 filtered out; finished in 4.55s

error: doctest failed, to rerun pass `-p rustc_lint_defs --doc`
  local time: Sun Dec 15 02:08:36 UTC 2024
  network time: Sun, 15 Dec 2024 02:08:36 GMT
##[error]Process completed with exit code 1.
Post job cleanup.

[iSwapna]

Not sure if we should turn the warning and test with build-fail ( since CI core dumps) or the warning needs to be an error. The failure is in doc-tests. I believe it's the latter, but want to be sure. @estebank