From facd44c2ec235bb562ee1ca09ba4f305f8822b86 Mon Sep 17 00:00:00 2001
From: Neven Sajko <s@purelymail.com>
Date: Sat, 22 Mar 2025 13:07:39 +0100
Subject: [PATCH] `Base`: `macro b_str`: restrict argument to `String`

Should make the sysimage less vulnerable to invalidation.

As far as I understand this change can't break any code, because:
* the macro definition requires `AbstractString`
* the way Julia macros work, the argument is either a literal or an `Expr`
* `String` is the only `AbstractString` with literals
---
 base/strings/io.jl | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/base/strings/io.jl b/base/strings/io.jl
index d072786923304..f321376dbee50 100644
--- a/base/strings/io.jl
+++ b/base/strings/io.jl
@@ -585,7 +585,7 @@ julia> v[2]
 0x32
 ```
 """
-macro b_str(s)
+macro b_str(s::String)
     v = codeunits(unescape_string(s))
     QuoteNode(v)
 end