From eb449c133903c6b274580f8e365a3f287670d667 Mon Sep 17 00:00:00 2001
From: bjorn3 <17426603+bjorn3@users.noreply.github.com>
Date: Tue, 4 Jun 2024 16:02:36 +0200
Subject: [PATCH] Move error on -Cinstrument-coverage earlier and elaborate
 that it is LLVM specific

cc rust-lang/rustc_codegen_cranelift#1494
---
 src/lib.rs | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/src/lib.rs b/src/lib.rs
index 39bbad16b0c..9eece684b1a 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -172,7 +172,7 @@ impl CodegenBackend for CraneliftCodegenBackend {
     }
 
     fn init(&self, sess: &Session) {
-        use rustc_session::config::Lto;
+        use rustc_session::config::{InstrumentCoverage, Lto};
         match sess.lto() {
             Lto::No | Lto::ThinLocal => {}
             Lto::Thin | Lto::Fat => {
@@ -180,6 +180,11 @@ impl CodegenBackend for CraneliftCodegenBackend {
             }
         }
 
+        if sess.opts.cg.instrument_coverage() != InstrumentCoverage::No {
+            sess.dcx()
+                .fatal("`-Cinstrument-coverage` is LLVM specific and not supported by Cranelift");
+        }
+
         let mut config = self.config.borrow_mut();
         if config.is_none() {
             let new_config = BackendConfig::from_opts(&sess.opts.cg.llvm_args)