From 852684d306cee955ed751f1e8d8eec6adaecff3b Mon Sep 17 00:00:00 2001
From: Joshua Nelson <jyn514@gmail.com>
Date: Mon, 8 Feb 2021 22:51:21 -0500
Subject: [PATCH] Use format string in bootstrap panic instead of a string
 directly

This fixes the following warning when compiling with nightly:

```
warning: panic message is not a string literal
    --> src/bootstrap/builder.rs:1515:24
     |
1515 |                 panic!(out);
     |                        ^^^
     |
     = note: `#[warn(non_fmt_panic)]` on by default
     = note: this is no longer accepted in Rust 2021
help: add a "{}" format string to Display the message
     |
1515 |                 panic!("{}", out);
     |                        ^^^^^
help: or use std::panic::panic_any instead
     |
1515 |                 std::panic::panic_any(out);
     |                 ^^^^^^^^^^^^^^^^^^^^^^
```

(cherry picked from commit 31c93397bde772764cda3058e16f9cef61895090)
---
 src/bootstrap/builder.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/bootstrap/builder.rs b/src/bootstrap/builder.rs
index f1a160250dbe..0f5fcb4af400 100644
--- a/src/bootstrap/builder.rs
+++ b/src/bootstrap/builder.rs
@@ -1490,7 +1490,7 @@ pub fn ensure<S: Step>(&'a self, step: S) -> S::Output {
                 for el in stack.iter().rev() {
                     out += &format!("\t{:?}\n", el);
                 }
-                panic!(out);
+                panic!("{}", out);
             }
             if let Some(out) = self.cache.get(&step) {
                 self.verbose(&format!("{}c {:?}", "  ".repeat(stack.len()), step));
-- 
2.31.1