uplift some -Zverbose calls and rename to -Zverbose-internals

[jyn514]

Proposal

right now, --verbose has exactly one effect, which is to print more information for --version: https://github.com/rust-lang/rust/blob/558ac1cfb7c214d06ca471885a57caa6c8301bae/compiler/rustc_driver_impl/src/lib.rs#L884

this seems kind of silly. there are lots of other places where the compiler adds more info based on -Z verbose. some of these are quite useful to show in diagnostics, for example showing full types in a type error rather than eliding similar types with _. it would be nice to display those when --verbose is passed.

furthermore, it's confusing to have both --verbose and -Z verbose. i suggest renaming the internal flag (perhaps -Z verbose-internals makes it clear that it's not meant to be useful for anyone but compiler devs?).

; rg '\.verbose\(' compiler -l
compiler/rustc_driver_impl/src/pretty.rs
compiler/rustc_middle/src/mir/pretty.rs
compiler/rustc_middle/src/ty/generics.rs
compiler/rustc_middle/src/ty/print/pretty.rs
compiler/rustc_hir_typeck/src/expr.rs
compiler/rustc_infer/src/traits/structural_impls.rs
compiler/rustc_query_impl/src/plumbing.rs
compiler/rustc_infer/src/infer/error_reporting/mod.rs

Mentors or Reviewers

@compiler-errors

Process

The main points of the Major Change Process are as follows:

• File an issue describing the proposal.
• A compiler team member or contributor who is knowledgeable in the area can second by writing @rustbot second.
  • Finding a "second" suffices for internal changes. If however, you are proposing a new public-facing feature, such as a -C flag, then full team check-off is required.
  • Compiler team members can initiate a check-off via @rfcbot fcp merge on either the MCP or the PR.
• Once an MCP is seconded, the Final Comment Period begins. If no objections are raised after 10 days, the MCP is considered approved.

You can read more about Major Change Proposals on forge.

Comments

This issue is not meant to be used for technical discussion. There is a Zulip stream for that. Use this issue to leave procedural comments, such as volunteering to review, indicating that you second the proposal (or third, etc), or raising a concern that you would like to be addressed.

[rustbot]

This issue is not meant to be used for technical discussion. There is a Zulip stream for that. Use this issue to leave procedural comments, such as volunteering to review, indicating that you second the proposal (or third, etc), or raising a concern that you would like to be addressed.

Concerns or objections to the proposal should be discussed on Zulip and formally registered here by adding a comment with the following syntax:

@rustbot concern reason-for-concern 
<description of the concern> 

Concerns can be lifted with:

@rustbot resolve reason-for-concern 

See documentation at https://forge.rust-lang.org

cc @rust-lang/compiler @rust-lang/compiler-contributors

[estebank]

Follow @compiler-errors' guidance from the zulip thread.

@rustbot second

[apiraino]

@rustbot label -final-comment-period +major-change-accepted