1 files changed, 10 insertions, 1 deletions
diff --git a/compiler/rustc_span/src/source_map.rs b/compiler/rustc_span/src/source_map.rs
index e74a5c2d8fe..55e106b661b 100644
--- a/compiler/rustc_span/src/source_map.rs
+++ b/compiler/rustc_span/src/source_map.rs
@@ -115,6 +115,12 @@ impl FileLoader for RealFileLoader {
     }
 
     fn read_file(&self, path: &Path) -> io::Result<String> {
+        if path.metadata().is_ok_and(|metadata| metadata.len() > SourceFile::MAX_FILE_SIZE.into()) {
+            return Err(io::Error::other(format!(
+                "text files larger than {} bytes are unsupported",
+                SourceFile::MAX_FILE_SIZE
+            )));
+        }
         fs::read_to_string(path)
     }
 
@@ -297,7 +303,10 @@ impl SourceMap {
     /// unmodified.
     pub fn new_source_file(&self, filename: FileName, src: String) -> Lrc<SourceFile> {
         self.try_new_source_file(filename, src).unwrap_or_else(|OffsetOverflowError| {
-            eprintln!("fatal error: rustc does not support files larger than 4GB");
+            eprintln!(
+                "fatal error: rustc does not support text files larger than {} bytes",
+                SourceFile::MAX_FILE_SIZE
+            );
             crate::fatal_error::FatalError.raise()
         })
     }