diff --git a/src/lib.rs b/src/lib.rs
index 96b5624f..b026eb18 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -86,7 +86,7 @@ extern "C" fn eh_personality() {}
 
 #[cfg(not(test))]
 #[lang = "panic_fmt"]
-extern "C" fn panic_fmt(fmt: core::fmt::Arguments, file: &str, line: u32) -> ! {
+extern "C" fn panic_fmt(fmt: core::fmt::Arguments, file: &'static str, line: u32) -> ! {
     println!("\n\nPANIC in {} at line {}:", file, line);
     println!("    {}", fmt);
     loop {}