Auto merge of #129999 - matthiaskrgr:rollup-pzr9c8p, r=matthiaskrgr

Rollup of 11 pull requests

Successful merges:

 - #128919 (Add an internal lint that warns when accessing untracked data)
 - #129472 (fix ICE when `asm_const` and `const_refs_to_static` are combined)
 - #129653 (clarify that addr_of creates read-only pointers)
 - #129775 (bootstrap: Try to track down why `initial_libdir` sometimes fails)
 - #129939 (explain why Rvalue::Len still exists)
 - #129942 (copy rustc rustlib artifacts from ci-rustc)
 - #129943 (use the bootstrapped compiler for `test-float-parse` test)
 - #129944 (Add compat note for trait solver change)
 - #129947 (Add digit separators in `Duration` examples)
 - #129955 (Temporarily remove fmease from the review rotation)
 - #129957 (forward linker option to lint-docs)

r? `@ghost`
`@rustbot` modify labels: rollup

compiler/rustc_lint/messages.ftl

@@ -699,6 +699,9 @@ lint_ptr_null_checks_ref = references are not nullable, so checking them for nul
 lint_query_instability = using `{$query}` can result in unstable query results
     .note = if you believe this case to be fine, allow this lint and add a comment explaining your rationale
 
+lint_query_untracked = `{$method}` accesses information that is not tracked by the query system
+    .note = if you believe this case to be fine, allow this lint and add a comment explaining your rationale
+
 lint_range_endpoint_out_of_range = range endpoint is out of range for `{$ty}`
 
 lint_range_use_inclusive_range = use an inclusive range instead

compiler/rustc_lint/src/internal.rs

@@ -17,8 +17,8 @@ use tracing::debug;
 
 use crate::lints::{
     BadOptAccessDiag, DefaultHashTypesDiag, DiagOutOfImpl, LintPassByHand, NonExistentDocKeyword,
-    NonGlobImportTypeIrInherent, QueryInstability, SpanUseEqCtxtDiag, TyQualified, TykindDiag,
-    TykindKind, TypeIrInherentUsage, UntranslatableDiag,
+    NonGlobImportTypeIrInherent, QueryInstability, QueryUntracked, SpanUseEqCtxtDiag, TyQualified,
+    TykindDiag, TykindKind, TypeIrInherentUsage, UntranslatableDiag,
 };
 use crate::{EarlyContext, EarlyLintPass, LateContext, LateLintPass, LintContext};
 
@@ -88,7 +88,18 @@ declare_tool_lint! {
     report_in_external_macro: true
 }
 
-declare_lint_pass!(QueryStability => [POTENTIAL_QUERY_INSTABILITY]);
+declare_tool_lint! {
+    /// The `untracked_query_information` lint detects use of methods which leak information not
+    /// tracked by the query system, such as whether a `Steal<T>` value has already been stolen. In
+    /// order not to break incremental compilation, such methods must be used very carefully or not
+    /// at all.
+    pub rustc::UNTRACKED_QUERY_INFORMATION,
+    Allow,
+    "require explicit opt-in when accessing information not tracked by the query system",
+    report_in_external_macro: true
+}
+
+declare_lint_pass!(QueryStability => [POTENTIAL_QUERY_INSTABILITY, UNTRACKED_QUERY_INFORMATION]);
 
 impl LateLintPass<'_> for QueryStability {
     fn check_expr(&mut self, cx: &LateContext<'_>, expr: &Expr<'_>) {
@@ -102,6 +113,13 @@ impl LateLintPass<'_> for QueryStability {
                     QueryInstability { query: cx.tcx.item_name(def_id) },
                 );
             }
+            if cx.tcx.has_attr(def_id, sym::rustc_lint_untracked_query_information) {
+                cx.emit_span_lint(
+                    UNTRACKED_QUERY_INFORMATION,
+                    span,
+                    QueryUntracked { method: cx.tcx.item_name(def_id) },
+                );
+            }
         }
     }
 }

compiler/rustc_lint/src/lib.rs

@@ -610,6 +610,7 @@ fn register_internals(store: &mut LintStore) {
         vec![
             LintId::of(DEFAULT_HASH_TYPES),
             LintId::of(POTENTIAL_QUERY_INSTABILITY),
+            LintId::of(UNTRACKED_QUERY_INFORMATION),
             LintId::of(USAGE_OF_TY_TYKIND),
             LintId::of(PASS_BY_VALUE),
             LintId::of(LINT_PASS_IMPL_WITHOUT_MACRO),

compiler/rustc_lint/src/lints.rs

@@ -894,6 +894,13 @@ pub(crate) struct QueryInstability {
     pub query: Symbol,
 }
 
+#[derive(LintDiagnostic)]
+#[diag(lint_query_untracked)]
+#[note]
+pub(crate) struct QueryUntracked {
+    pub method: Symbol,
+}
+
 #[derive(LintDiagnostic)]
 #[diag(lint_span_use_eq_ctxt)]
 pub(crate) struct SpanUseEqCtxtDiag;