FFI: bugfix: GC-correctness of assignments.

Recent work has introduced wrong-way assignments. When we
compile the slots after we have created the type object, the
slot types may be in a newer generation than the type object.
If we are reusing an old type object, it can be older than
the syntax, or the Lisp object being stored in it.

* ffi.c (make_ffi_type_struct, make_ffi_type_union): add some
setcheck calls to handle anti-generational assignments.

1 files changed, 11 insertions, 0 deletions

diff --git a/ffi.c b/ffi.c
index 450bc904..0b426703 100644
--- a/ffi.c
+++ b/ffi.c
@@ -2882,6 +2882,9 @@ static val make_ffi_type_struct(val syntax, val lisp_type,
 
   tft->incomplete = 1;
 
+  setcheck(obj, syntax);
+  setcheck(obj, lisp_type);
+
   sethash(ffi_struct_tag_hash, cadr(syntax), obj);
 
   for (i = 0; i < nmemb; i++) {
@@ -2897,6 +2900,9 @@ static val make_ffi_type_struct(val syntax, val lisp_type,
     memb[i].mname = slot;
     memb[i].mtft = mtft;
 
+    setcheck(obj, slot);
+    setcheck(obj, type);
+
     if (mtft->bitfield) {
       ucnum size = mtft->size;
       ucnum bits_type = 8 * size;
@@ -3045,6 +3051,8 @@ static val make_ffi_type_union(val syntax, val use_existing, val self)
 
   tft->incomplete = 1;
 
+  setcheck(obj, syntax);
+
   sethash(ffi_struct_tag_hash, cadr(syntax), obj);
 
   for (i = 0; i < nmemb; i++) {
@@ -3058,6 +3066,9 @@ static val make_ffi_type_union(val syntax, val use_existing, val self)
     memb[i].mtft = mtft;
     memb[i].offs = 0;
 
+    setcheck(obj, slot);
+    setcheck(obj, type);
+
     if (most_align < (ucnum) mtft->align)
       most_align = mtft->align;