1 files changed, 1 insertions, 0 deletions

diff --git a/src/lisp.h b/src/lisp.h
index 86d9c85b547..60ed8c1d3ec 100644
--- a/src/lisp.h
+++ b/src/lisp.h
@@ -1186,6 +1186,7 @@ extern Lisp_Object Fpurecopy (), make_pure_string ();
 extern Lisp_Object pure_cons (), make_pure_vector ();
 extern Lisp_Object Fgarbage_collect ();
 extern Lisp_Object Fmake_byte_code ();
+extern int gc_in_progress;
 
 /* Defined in print.c */
 extern Lisp_Object Vprin1_to_string_buffer;