Auto merge of #126569 - jieyouxu:rollup-1uvkb2y, r=jieyouxu

Rollup of 8 pull requests

Successful merges:

 - #125258 (Resolve elided lifetimes in assoc const to static if no other lifetimes are in scope)
 - #126250 (docs(change): Don't mention a Cargo 2024 edition change for 1.79)
 - #126288 (doc: Added commas where needed)
 - #126346 (export std::os::fd module on HermitOS)
 - #126468 (div_euclid, rem_euclid: clarify/extend documentation)
 - #126531 (Add codegen test for `Request::provide_*`)
 - #126535 (coverage: Arrange span extraction/refinement as a series of passes)
 - #126538 (coverage: Several small improvements to graph code)

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

1 files changed, 50 insertions, 0 deletions

diff --git a/tests/codegen/error-provide.rs b/tests/codegen/error-provide.rs
new file mode 100644
index 00000000000..68dd383e5cc
--- /dev/null
+++ b/tests/codegen/error-provide.rs
@@ -0,0 +1,50 @@
+// Codegen test for #126242
+
+//@ compile-flags: -O
+#![crate_type = "lib"]
+#![feature(error_generic_member_access)]
+use std::error::Request;
+use std::fmt;
+
+#[derive(Debug)]
+struct MyBacktrace1 {}
+
+#[derive(Debug)]
+struct MyBacktrace2 {}
+
+#[derive(Debug)]
+struct MyBacktrace3 {}
+
+#[derive(Debug)]
+struct MyError {
+    backtrace1: MyBacktrace1,
+    backtrace2: MyBacktrace2,
+    backtrace3: MyBacktrace3,
+    other: MyBacktrace3,
+}
+
+impl fmt::Display for MyError {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        write!(f, "Example Error")
+    }
+}
+
+impl std::error::Error for MyError {
+    // CHECK-LABEL: @provide
+    #[no_mangle]
+    fn provide<'a>(&'a self, request: &mut Request<'a>) {
+        // LLVM should be able to optimize multiple .provide_* calls into a switch table
+        // and eliminate redundant ones, rather than compare one-by-one.
+
+        // CHECK-NEXT: start:
+        // CHECK-NEXT: %[[SCRUTINEE:[^ ]+]] = load i64, ptr
+        // CHECK-NEXT: switch i64 %[[SCRUTINEE]], label %{{.*}} [
+        // CHECK-COUNT-3: i64 {{.*}}, label %{{.*}}
+        // CHECK-NEXT: ]
+        request
+            .provide_ref::<MyBacktrace1>(&self.backtrace1)
+            .provide_ref::<MyBacktrace3>(&self.other)
+            .provide_ref::<MyBacktrace2>(&self.backtrace2)
+            .provide_ref::<MyBacktrace3>(&self.backtrace3);
+    }
+}