Nice idea: how about a function which walks the tree structure and

back-fills some missing source code location info.  We apply this to
macro expansions.  If some error occurs in expanded code, this way it
is referenced to the line where the macro *call* occurs.
Not only is this better than nothing, it may be better than tracing
it to the macro definition. Ideally, we would have both places:
("the error is in the code expanded from this macro, at this site").

* eval.c (expand): Use rlcp_tree to back-fill source info in
macro expansion by taking it from the unexpanded form.

* parser.h (rlcp_tree): Declared.

* parser.y (rlcp_tree): New function.

1 files changed, 13 insertions, 0 deletions

diff --git a/parser.y b/parser.y
index 797d3711..a4a7aa61 100644
--- a/parser.y
+++ b/parser.y
@@ -1149,6 +1149,19 @@ val rlset(val form, val info)
   return form;
 }
 
+val rlcp_tree(val to, val from)
+{
+  if (atom(to)) {
+    return nil;
+  } else {
+    if (!source_loc(to))
+      rlcp(to, from);
+    for (; consp(to); to = cdr(to))
+      rlcp_tree(car(to), from);
+    return t;
+  }
+}
+
 static wchar_t char_from_name(const wchar_t *name)
 {
   static struct {