Auto merge of #144490 - tgross35:rollup-ps0utme, r=tgross35

Rollup of 9 pull requests

Successful merges:

 - rust-lang/rust#140871 (Don't lint against named labels in `naked_asm!`)
 - rust-lang/rust#141663 (rustdoc: add ways of collapsing all impl blocks)
 - rust-lang/rust#143272 (Upgrade the `fortanix-sgx-abi` dependency)
 - rust-lang/rust#143585 (`loop_match`: suggest extracting to a `const` item)
 - rust-lang/rust#143698 (Fix unused_parens false positive)
 - rust-lang/rust#143859 (Guarantee 8 bytes of alignment in Thread::into_raw)
 - rust-lang/rust#144160 (tests: debuginfo: Work around or disable broken tests on powerpc)
 - rust-lang/rust#144412 (Small cleanup: Use LocalKey<Cell> methods more)
 - rust-lang/rust#144431 (Disable has_reliable_f128_math on musl targets)

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

2 files changed, 58 insertions, 3 deletions

diff --git a/compiler/rustc_mir_build/src/builder/scope.rs b/compiler/rustc_mir_build/src/builder/scope.rs
index 12a56d7c5ea..1240b34cf9d 100644
--- a/compiler/rustc_mir_build/src/builder/scope.rs
+++ b/compiler/rustc_mir_build/src/builder/scope.rs
@@ -100,7 +100,9 @@ use tracing::{debug, instrument};
 
 use super::matches::BuiltMatchTree;
 use crate::builder::{BlockAnd, BlockAndExtension, BlockFrame, Builder, CFG};
-use crate::errors::{ConstContinueBadConst, ConstContinueUnknownJumpTarget};
+use crate::errors::{
+    ConstContinueBadConst, ConstContinueNotMonomorphicConst, ConstContinueUnknownJumpTarget,
+};
 
 #[derive(Debug)]
 pub(crate) struct Scopes<'tcx> {
@@ -867,7 +869,8 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
             span_bug!(span, "break value must be a scope")
         };
 
-        let constant = match &self.thir[value].kind {
+        let expr = &self.thir[value];
+        let constant = match &expr.kind {
             ExprKind::Adt(box AdtExpr { variant_index, fields, base, .. }) => {
                 assert!(matches!(base, AdtExprBase::None));
                 assert!(fields.is_empty());
@@ -887,7 +890,27 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
                     ),
                 }
             }
-            _ => self.as_constant(&self.thir[value]),
+
+            ExprKind::Literal { .. }
+            | ExprKind::NonHirLiteral { .. }
+            | ExprKind::ZstLiteral { .. }
+            | ExprKind::NamedConst { .. } => self.as_constant(&self.thir[value]),
+
+            other => {
+                use crate::errors::ConstContinueNotMonomorphicConstReason as Reason;
+
+                let span = expr.span;
+                let reason = match other {
+                    ExprKind::ConstParam { .. } => Reason::ConstantParameter { span },
+                    ExprKind::ConstBlock { .. } => Reason::ConstBlock { span },
+                    _ => Reason::Other { span },
+                };
+
+                self.tcx
+                    .dcx()
+                    .emit_err(ConstContinueNotMonomorphicConst { span: expr.span, reason });
+                return block.unit();
+            }
         };
 
         let break_index = self
diff --git a/compiler/rustc_mir_build/src/errors.rs b/compiler/rustc_mir_build/src/errors.rs
index 16b49bf384c..f1fbd5c4a49 100644
--- a/compiler/rustc_mir_build/src/errors.rs
+++ b/compiler/rustc_mir_build/src/errors.rs
@@ -1214,6 +1214,38 @@ pub(crate) struct LoopMatchArmWithGuard {
 }
 
 #[derive(Diagnostic)]
+#[diag(mir_build_const_continue_not_const)]
+#[help]
+pub(crate) struct ConstContinueNotMonomorphicConst {
+    #[primary_span]
+    pub span: Span,
+
+    #[subdiagnostic]
+    pub reason: ConstContinueNotMonomorphicConstReason,
+}
+
+#[derive(Subdiagnostic)]
+pub(crate) enum ConstContinueNotMonomorphicConstReason {
+    #[label(mir_build_const_continue_not_const_constant_parameter)]
+    ConstantParameter {
+        #[primary_span]
+        span: Span,
+    },
+
+    #[label(mir_build_const_continue_not_const_const_block)]
+    ConstBlock {
+        #[primary_span]
+        span: Span,
+    },
+
+    #[label(mir_build_const_continue_not_const_const_other)]
+    Other {
+        #[primary_span]
+        span: Span,
+    },
+}
+
+#[derive(Diagnostic)]
 #[diag(mir_build_const_continue_bad_const)]
 pub(crate) struct ConstContinueBadConst {
     #[primary_span]