From 7f6dce43829b915cbaa5d49625506fd060e2c6d6 Mon Sep 17 00:00:00 2001
From: EFanZh <efanzh@gmail.com>
Date: Tue, 23 Dec 2025 12:41:42 +0800
Subject: [PATCH] Constify `fmt::from_fn`

---
 library/core/src/fmt/builders.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/library/core/src/fmt/builders.rs b/library/core/src/fmt/builders.rs
index 197cddd3fa9de..1a7db8719b404 100644
--- a/library/core/src/fmt/builders.rs
+++ b/library/core/src/fmt/builders.rs
@@ -1228,7 +1228,7 @@ impl<'a, 'b: 'a> DebugMap<'a, 'b> {
 /// ```
 #[stable(feature = "fmt_from_fn", since = "1.93.0")]
 #[must_use = "returns a type implementing Debug and Display, which do not have any effects unless they are used"]
-pub fn from_fn<F: Fn(&mut fmt::Formatter<'_>) -> fmt::Result>(f: F) -> FromFn<F> {
+pub const fn from_fn<F: Fn(&mut fmt::Formatter<'_>) -> fmt::Result>(f: F) -> FromFn<F> {
     FromFn(f)
 }