[pcshrosbree]

--ignore-error and --ignore-error-file match regular expressions against error names, but ILVerify does not list those names anywhere. This PR adds a --list-errors option that prints them:

• every VerifierError name except None, with its message from Strings.resx;
• every ExceptionStringID name;
• a line saying that an error with neither kind of name matches None.

The issue proposed --help --verbose for this. I used a separate option instead, which the issue offered as the alternative. Plain --help now shows the option with its own description, and --verbose keeps its one meaning, verbose verification output.

Like --help, --list-errors works without input files. If input files are given, it prints the list and does not verify them. Plain --help gains one line:

  --list-errors                            List the error names that --ignore-error matches

The output looks like this:

Verification errors (--ignore-error matches these names):
  UnknownOpcode: Unknown opcode.
  MethodFallthrough: Fall through end of the method without returning.
  ...
  UnalignedAlignment: Alignment specified for 'unaligned.' must be 1, 2, or 4.

Type system errors (--ignore-error also matches these names):
  ClassLoadGeneral
  ClassLoadExplicitGeneric
  ...
  AmbiguousMatchUnsafeAccessor

An error with neither kind of name, such as an exception while verifying a method, matches None.

Five messages contain placeholders such as '{0}', which ILVerify fills in when it reports the error. The list shows them unfilled.

Testing

ILVerify has no command-line tests, so I checked a build of this branch against a build of main:

• --list-errors with no input files exits with 0. It prints 124 verification error names (all of VerifierError except None) and 25 type system names (all of ExceptionStringID). Both lists follow declaration order. Each verification error name is printed with its Strings.resx message.
• Plain --help differs from main only by the new line.
• --ignore-error accepts a name from each list. On the ReturnTests assembly from ILVerification.Tests, --ignore-error "^ReturnPtrToStack$" removed both ReturnPtrToStack errors and nothing else. On InvalidMetadataReferenceTests, --ignore-error "^ClassLoadGeneral$" removed the five ClassLoadGeneral errors.
• ILVerification.Tests passes: 513 of 513.

Fixes #136056

Note

This PR was prepared with AI assistance (Anthropic Claude and OpenAI Codex), under my direction. I reviewed it before posting.

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[jkotas]

Thanks

[jkotas]

/ba-g System.Runtime.Tests failure is known issue that just got fixed

[pcshrosbree]

Thank you for the review and merge!