headers: check that _GL_INLINE_HEADER_BEGIN is defined

[gnulib.git] / lib / gl_xsublist.h

diff --git a/lib/gl_xsublist.h b/lib/gl_xsublist.h
index 725d3e1..53898ec 100644 (file)
--- a/lib/gl_xsublist.h
+++ b/lib/gl_xsublist.h
@@ -22,6 +22,9 @@
 #include "gl_sublist.h"
 #include "xalloc.h"
 
+#ifndef _GL_INLINE_HEADER_BEGIN
+ #error "Please include config.h first."
+#endif
 _GL_INLINE_HEADER_BEGIN
 #ifndef GL_XSUBLIST_INLINE
 # define GL_XSUBLIST_INLINE _GL_INLINE