--- a/src/structs.h
+++ b/src/structs.h
@@ -1735,40 +1735,40 @@ typedef struct
  */
 struct funccall_S
 {
-    ufunc_T	*func;		// function being called
-    int		linenr;		// next line to be executed
-    int		returned;	// ":return" used
+    ufunc_T	*fc_func;	// function being called
+    int		fc_linenr;	// next line to be executed
+    int		fc_returned;	// ":return" used
     struct			// fixed variables for arguments
     {
 	dictitem_T	var;		// variable (without room for name)
 	char_u	room[VAR_SHORT_LEN];	// room for the name
-    } fixvar[FIXVAR_CNT];
-    dict_T	l_vars;		// l: local function variables
-    dictitem_T	l_vars_var;	// variable for l: scope
-    dict_T	l_avars;	// a: argument variables
-    dictitem_T	l_avars_var;	// variable for a: scope
-    list_T	l_varlist;	// list for a:000
-    listitem_T	l_listitems[MAX_FUNC_ARGS];	// listitems for a:000
-    typval_T	*rettv;		// return value
-    linenr_T	breakpoint;	// next line with breakpoint or zero
-    int		dbg_tick;	// debug_tick when breakpoint was set
-    int		level;		// top nesting level of executed function
+    } fc_fixvar[FIXVAR_CNT];
+    dict_T	fc_l_vars;	// l: local function variables
+    dictitem_T	fc_l_vars_var;	// variable for l: scope
+    dict_T	fc_l_avars;	// a: argument variables
+    dictitem_T	fc_l_avars_var;	// variable for a: scope
+    list_T	fc_l_varlist;	// list for a:000
+    listitem_T	fc_l_listitems[MAX_FUNC_ARGS];	// listitems for a:000
+    typval_T	*fc_rettv;	// return value
+    linenr_T	fc_breakpoint;	// next line with breakpoint or zero
+    int		fc_dbg_tick;	// debug_tick when breakpoint was set
+    int		fc_level;	// top nesting level of executed function
 
     garray_T	fc_defer;	// functions to be called on return
     ectx_T	*fc_ectx;	// execution context for :def function, NULL
 				// otherwise
 
 #ifdef FEAT_PROFILE
-    proftime_T	prof_child;	// time spent in a child
+    proftime_T	fc_prof_child;	// time spent in a child
 #endif
-    funccall_T	*caller;	// calling function or NULL; or next funccal in
+    funccall_T	*fc_caller;	// calling function or NULL; or next funccal in
 				// list pointed to by previous_funccal.
 
     // for closure
     int		fc_refcount;	// number of user functions that reference this
 				// funccal
     int		fc_copyID;	// for garbage collection
-    garray_T	fc_funcs;	// list of ufunc_T* which keep a reference to
+    garray_T	fc_ufuncs;	// list of ufunc_T* which keep a reference to
 				// "func"
 };