Rollup merge of #117256 - dtolnay:currentversion, r=compiler-errors

Parse rustc version at compile time

This PR eliminates a couple awkward codepaths where it was not clear how the compiler should proceed if its own version number is incomprehensible.

https://github.com/rust-lang/rust/blob/dab715641e96a61a534587fda9de1128b75b34dc/src/tools/clippy/clippy_utils/src/qualify_min_const_fn.rs#L385

https://github.com/rust-lang/rust/blob/dab715641e96a61a534587fda9de1128b75b34dc/compiler/rustc_attr/src/builtin.rs#L630

We can guarantee that every compiled rustc comes with a working version number, so the ICE codepaths above shouldn't need to be written.

2 files changed, 11 insertions, 17 deletions

diff --git a/src/librustdoc/html/render/mod.rs b/src/librustdoc/html/render/mod.rs
index d9086433608..0b6079b2933 100644
--- a/src/librustdoc/html/render/mod.rs
+++ b/src/librustdoc/html/render/mod.rs
@@ -48,13 +48,14 @@ use std::str;
 use std::string::ToString;
 
 use askama::Template;
-use rustc_attr::{ConstStability, Deprecation, Since, StabilityLevel, CURRENT_RUSTC_VERSION};
+use rustc_attr::{ConstStability, Deprecation, Since, StabilityLevel};
 use rustc_data_structures::captures::Captures;
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 use rustc_hir::def_id::{DefId, DefIdSet};
 use rustc_hir::Mutability;
 use rustc_middle::middle::stability;
 use rustc_middle::ty::{self, TyCtxt};
+use rustc_session::RustcVersion;
 use rustc_span::{
     symbol::{sym, Symbol},
     BytePos, FileName, RealFileName,
@@ -979,7 +980,7 @@ fn render_stability_since_raw_with_extra(
 fn since_to_string(since: &Since) -> Option<String> {
     match since {
         Since::Version(since) => Some(since.to_string()),
-        Since::Current => Some(CURRENT_RUSTC_VERSION.to_owned()),
+        Since::Current => Some(RustcVersion::CURRENT.to_string()),
         Since::Err => None,
     }
 }
diff --git a/src/tools/clippy/clippy_utils/src/qualify_min_const_fn.rs b/src/tools/clippy/clippy_utils/src/qualify_min_const_fn.rs
index 1e465ac91b7..31f7b87de63 100644
--- a/src/tools/clippy/clippy_utils/src/qualify_min_const_fn.rs
+++ b/src/tools/clippy/clippy_utils/src/qualify_min_const_fn.rs
@@ -5,7 +5,7 @@
 
 use crate::msrvs::Msrv;
 use hir::LangItem;
-use rustc_attr::{Since, CURRENT_RUSTC_VERSION};
+use rustc_attr::Since;
 use rustc_const_eval::transform::check_consts::ConstCx;
 use rustc_hir as hir;
 use rustc_hir::def_id::DefId;
@@ -372,23 +372,16 @@ fn is_const_fn(tcx: TyCtxt<'_>, def_id: DefId, msrv: &Msrv) -> bool {
                 // as a part of an unimplemented MSRV check https://github.com/rust-lang/rust/issues/65262.
 
                 let const_stab_rust_version = match since {
-                    Since::Version(version) => RustcVersion::new(
-                        u32::from(version.major),
-                        u32::from(version.minor),
-                        u32::from(version.patch),
-                    ),
-                    Since::Current => {
-                        // HACK(nilstrieb): CURRENT_RUSTC_VERSION can return versions like 1.66.0-dev.
-                        // `rustc-semver` doesn't accept the `-dev` version number so we have to strip it off.
-                        let short_version = CURRENT_RUSTC_VERSION.split('-').next().unwrap();
-                        RustcVersion::parse(short_version).unwrap_or_else(|err| {
-                            panic!("`rustc_attr::StabilityLevel::Stable::since` is ill-formatted: `{CURRENT_RUSTC_VERSION}`, {err:?}")
-                        })
-                    },
+                    Since::Version(version) => version,
+                    Since::Current => rustc_session::RustcVersion::CURRENT,
                     Since::Err => return false,
                 };
 
-                msrv.meets(const_stab_rust_version)
+                msrv.meets(RustcVersion::new(
+                    u32::from(const_stab_rust_version.major),
+                    u32::from(const_stab_rust_version.minor),
+                    u32::from(const_stab_rust_version.patch),
+                ))
             } else {
                 // Unstable const fn with the feature enabled.
                 msrv.current().is_none()