[llvm-lit] Enable lit internal shell by default

[connieyzhu]

This is a meta-issue that addresses the problem referenced in [RFC] Enabling the Lit Internal Shell by Default.

Brief problem summary: Many RUN line commands used in LLVM tests are written in a way that only works on POSIX-compliant shells, leading to issues on platforms like Windows or non-POSIX systems. To overcome these discrepancies, lit has an internal shell implementation designed to ensure uniform execution of these commands, regardless of the platform. Although the internal shell supports most common commands, it still lacks several capabilities that are necessary for it to become the default shell when running LLVM tests.

This meta-issue tracks the following issues: Subprojects:

• [ ] Enable internal shell for llvm test suite

Missing Capabilities Blocking Enablement:

• 102374

  102383

  102395

  106627

• [ ] Enable internal shell for clang test suite

Missing Capabilities Blocking Enablement:

• 106601

  102384

  102389

  106249

• [ ] Enable internal shell for lld test suite

Missing Capabilities Blocking Enablement:

• 106594

  102382

• [ ] Enable internal shell for lldb test suite

Missing Capabilities Blocking Enablement:

• 102377

  102696

• [ ] Enable internal shell for BOLT test suite

Missing Capabilities Blocking Enablement:

• 102388

  102401

  102693

  102399

• [ ] Enable internal shell for compiler-rt test suite

Missing Capabilities Blocking Enablement:

• 106598

  102398

  102397

  102695

  102386

  102399

  102389

  102380

  102385

  102384

  102401

  102382

  106142

  106111

• [ ] Enable internal shell for clang-tools-extra test suite

  Missing Capabilities Blocking Enablement:

  • 106302

• [x] Enable internal shell for polly test suite

  • 106459

• [x] Enable internal shell for mlir test suite (already the default)

  • 106459

• [ ] Enable internal shell for flang test suite
• [ ] Enable internal shell for libc test suite
• [x] Enable internal shell for libcxx test suite (already the default)
• [x] Enable internal shell for libunwind test suite (already the default)
• [x] Enable internal shell for libcxxabi test suite (already the default)

This is a comprehensive list of all the features to be implemented. Feature List:

• 102374

  102383

  102395

  106594

  106598

  106601

  102384

  102389

  102695

  102382

  102377

  102696

  102398

  102397

  102388

  102401

  102693

  102399

  102386

  102380

  102385

  106142

  106249

  106302

  106459

  106627

This issue will help track the progress of enabling the lit internal shell across all LLVM subprojects.

[connieyzhu]

@ldionne Hi there, it seems like libcxx in LLVM uses lit's internal shell as the default shell for running lit tests. Can you confirm if this is accurate?

[ldionne]

@ldionne Hi there, it seems like libcxx in LLVM uses lit's internal shell as the default shell for running lit tests. Can you confirm if this is accurate?

Yes, that's right. We made the transition some time ago (maybe 1-3 years) and haven't looked back.