Rollup merge of rust-lang#130305 - tspiteri:clippy-msrv-for-const_float_bits_conv, r=flip1995

Clippy: consider msrv for const context for const_float_bits_conv

When `const_float_bits_conv` was stabilized for 1.83.0, clippy lints started to be triggered in const context ignoring MSRV. This PR makes the lints trigger in const context only when the MSRV meets 1.83.0.

Fixes rust-lang/rust-clippy#13383.

Author: matthiaskrgr

src/tools/clippy/clippy_config/src/msrvs.rs

@@ -17,7 +17,8 @@ macro_rules! msrv_aliases {
 
 // names may refer to stabilized feature flags or library items
 msrv_aliases! {
-    1,81,0  { LINT_REASONS_STABILIZATION }
+    1,83,0 { CONST_FLOAT_BITS_CONV }
+    1,81,0 { LINT_REASONS_STABILIZATION }
     1,80,0 { BOX_INTO_ITER}
     1,77,0 { C_STR_LITERALS }
     1,76,0 { PTR_FROM_REF, OPTION_RESULT_INSPECT }

src/tools/clippy/clippy_lints/src/transmute/mod.rs

@@ -619,10 +619,10 @@ impl<'tcx> LateLintPass<'tcx> for Transmute {
                 | transmute_ref_to_ref::check(cx, e, from_ty, to_ty, arg, const_context)
                 | transmute_ptr_to_ptr::check(cx, e, from_ty, to_ty, arg, &self.msrv)
                 | transmute_int_to_bool::check(cx, e, from_ty, to_ty, arg)
-                | transmute_int_to_float::check(cx, e, from_ty, to_ty, arg)
+                | transmute_int_to_float::check(cx, e, from_ty, to_ty, arg, const_context, &self.msrv)
                 | transmute_int_to_non_zero::check(cx, e, from_ty, to_ty, arg)
-                | transmute_float_to_int::check(cx, e, from_ty, to_ty, arg)
-                | transmute_num_to_bytes::check(cx, e, from_ty, to_ty, arg)
+                | transmute_float_to_int::check(cx, e, from_ty, to_ty, arg, const_context, &self.msrv)
+                | transmute_num_to_bytes::check(cx, e, from_ty, to_ty, arg, const_context, &self.msrv)
                 | (unsound_collection_transmute::check(cx, e, from_ty, to_ty)
                     || transmute_undefined_repr::check(cx, e, from_ty, to_ty))
                 | (eager_transmute::check(cx, e, arg, from_ty, to_ty));

src/tools/clippy/clippy_lints/src/transmute/transmute_float_to_int.rs

@@ -1,4 +1,5 @@
 use super::TRANSMUTE_FLOAT_TO_INT;
+use clippy_config::msrvs::{self, Msrv};
 use clippy_utils::diagnostics::span_lint_and_then;
 use clippy_utils::sugg;
 use rustc_ast as ast;
@@ -15,9 +16,13 @@ pub(super) fn check<'tcx>(
     from_ty: Ty<'tcx>,
     to_ty: Ty<'tcx>,
     mut arg: &'tcx Expr<'_>,
+    const_context: bool,
+    msrv: &Msrv,
 ) -> bool {
     match (&from_ty.kind(), &to_ty.kind()) {
-        (ty::Float(float_ty), ty::Int(_) | ty::Uint(_)) => {
+        (ty::Float(float_ty), ty::Int(_) | ty::Uint(_))
+            if !const_context || msrv.meets(msrvs::CONST_FLOAT_BITS_CONV) =>
+        {
             span_lint_and_then(
                 cx,
                 TRANSMUTE_FLOAT_TO_INT,

src/tools/clippy/clippy_lints/src/transmute/transmute_int_to_float.rs

@@ -1,4 +1,5 @@
 use super::TRANSMUTE_INT_TO_FLOAT;
+use clippy_config::msrvs::{self, Msrv};
 use clippy_utils::diagnostics::span_lint_and_then;
 use clippy_utils::sugg;
 use rustc_errors::Applicability;
@@ -14,9 +15,11 @@ pub(super) fn check<'tcx>(
     from_ty: Ty<'tcx>,
     to_ty: Ty<'tcx>,
     arg: &'tcx Expr<'_>,
+    const_context: bool,
+    msrv: &Msrv,
 ) -> bool {
     match (&from_ty.kind(), &to_ty.kind()) {
-        (ty::Int(_) | ty::Uint(_), ty::Float(_)) => {
+        (ty::Int(_) | ty::Uint(_), ty::Float(_)) if !const_context || msrv.meets(msrvs::CONST_FLOAT_BITS_CONV) => {
             span_lint_and_then(
                 cx,
                 TRANSMUTE_INT_TO_FLOAT,

src/tools/clippy/clippy_lints/src/transmute/transmute_num_to_bytes.rs

@@ -1,4 +1,5 @@
 use super::TRANSMUTE_NUM_TO_BYTES;
+use clippy_config::msrvs::{self, Msrv};
 use clippy_utils::diagnostics::span_lint_and_then;
 use clippy_utils::sugg;
 use rustc_errors::Applicability;
@@ -14,12 +15,17 @@ pub(super) fn check<'tcx>(
     from_ty: Ty<'tcx>,
     to_ty: Ty<'tcx>,
     arg: &'tcx Expr<'_>,
+    const_context: bool,
+    msrv: &Msrv,
 ) -> bool {
     match (&from_ty.kind(), &to_ty.kind()) {
         (ty::Int(_) | ty::Uint(_) | ty::Float(_), ty::Array(arr_ty, _)) => {
             if !matches!(arr_ty.kind(), ty::Uint(UintTy::U8)) {
                 return false;
             }
+            if matches!(from_ty.kind(), ty::Float(_)) && const_context && !msrv.meets(msrvs::CONST_FLOAT_BITS_CONV) {
+                return false;
+            }
 
             span_lint_and_then(
                 cx,