--- a/src/Pure/System/isabelle_system.scala Sun Dec 11 14:16:09 2022 +0100
+++ b/src/Pure/System/isabelle_system.scala Sun Dec 11 18:50:21 2022 +0100
@@ -217,7 +217,9 @@
def copy_file_base(base_dir: Path, src: Path, target_dir: Path): Unit = {
val src1 = src.expand
val src1_dir = src1.dir
- if (!src1.starts_basic) error("Illegal path specification " + src1 + " beyond base directory")
+ if (!src1.starts_basic) {
+ error("Illegal path specification " + src1 + " beyond base directory " + base_dir.absolute)
+ }
copy_file(base_dir + src1, Isabelle_System.make_directory(target_dir + src1_dir))
}