From 669f610f741f41bc8b2bef41d088589db4180355 Mon Sep 17 00:00:00 2001
From: Veera <sveera.2001@gmail.com>
Date: Sat, 21 Sep 2024 11:23:34 -0400
Subject: Prevent Deduplication of `LongRunningWarn`

---
 compiler/rustc_const_eval/src/const_eval/machine.rs | 9 ++++++++-
 compiler/rustc_const_eval/src/errors.rs             | 2 ++
 2 files changed, 10 insertions(+), 1 deletion(-)

(limited to 'compiler/rustc_const_eval/src')

diff --git a/compiler/rustc_const_eval/src/const_eval/machine.rs b/compiler/rustc_const_eval/src/const_eval/machine.rs
index 7405ca09342..2025a465a22 100644
--- a/compiler/rustc_const_eval/src/const_eval/machine.rs
+++ b/compiler/rustc_const_eval/src/const_eval/machine.rs
@@ -641,7 +641,14 @@ impl<'tcx> interpret::Machine<'tcx> for CompileTimeMachine<'tcx> {
                 // current number of evaluated terminators is a power of 2. The latter gives us a cheap
                 // way to implement exponential backoff.
                 let span = ecx.cur_span();
-                ecx.tcx.dcx().emit_warn(LongRunningWarn { span, item_span: ecx.tcx.span });
+                // We store a unique number in `force_duplicate` to evade `-Z deduplicate-diagnostics`.
+                // `new_steps` is guaranteed to be unique because `ecx.machine.num_evaluated_steps` is
+                // always increasing.
+                ecx.tcx.dcx().emit_warn(LongRunningWarn {
+                    span,
+                    item_span: ecx.tcx.span,
+                    force_duplicate: new_steps,
+                });
             }
         }
 
diff --git a/compiler/rustc_const_eval/src/errors.rs b/compiler/rustc_const_eval/src/errors.rs
index 0b366b43f95..bdd8c66bc24 100644
--- a/compiler/rustc_const_eval/src/errors.rs
+++ b/compiler/rustc_const_eval/src/errors.rs
@@ -243,6 +243,8 @@ pub struct LongRunningWarn {
     pub span: Span,
     #[help]
     pub item_span: Span,
+    // Used for evading `-Z deduplicate-diagnostics`.
+    pub force_duplicate: usize,
 }
 
 #[derive(Subdiagnostic)]
-- 
cgit 1.4.1-3-g733a5