refactor octave_function call method This change is a step toward keeping stack frames for closures (handles to nested functions) separate from the functions themselves. * call-stack.h, call-stack.cc (call_stack::curr_fcn_unwind_protect_frame: No longer const. Update all uses. (call_stack::push): Dliminate unwind protect frame argument. Change all uses. * stack-frame.h, stack-frame.cc (script_stack_frame, user_fcn_stack_frame): Create uniwnd_protect_frame only if needed. * ov-builtin.h, ov-builtin.cc (octave_builtin::execute): New function that executes function without pushing stack frame. (octave_builtin::call): Delete. * ov-class.h, ov-class.cc (octave_inline_fcn::execute): New function. (octave_inline_fcn::call): Call execute. * ov-classdef.h, ov-classdef.cc (octave_classdef_meta::execute): New function. (octave_classdef_meta::call): Call execute. (octave_classdef_superclass_ref::execute): New function. (octave_classdef_superclass_ref::call): Call execute. * ov-fcn-handle.cc (octave_fcn_handle::call): When calling a function that has closure_frames, push stack frame here instead of inside octave_user_function object. * ov-fcn.h (octave_function::execute): New pure virtual function. * ov-fcn.h, ov-fcn.cc (octave_function::call): Define only one variant, without closure frames as an argument. Default version simply pushes stack frame and calls execute. * ov-mex-fcn.h, ov-mex-fcn.cc (octave_mex_function::execute): Rename from call. Don't push stack frame here. * ov-usr-fcn.h, ov-usr-fcn.cc (octave_user_script::call, octave_user_function::call): Push stack frame and call execute. (octave_user_script::execute, octave_user_function::execute): New function. * pt-eval.h, pt-eval.cc (tree_evaluator::push_stack_frame): Eliminate unwind protect frame argument. Change all uses. (tree_evaluator::execute_user_script): Update. (tree_evaluator::execute_user_function): Update. Don't push stack frame here.

--- a/libinterp/octave-value/ov-builtin.cc	Mon Mar 23 15:44:30 2020 -0400
+++ b/libinterp/octave-value/ov-builtin.cc	Mon Mar 30 10:43:47 2020 -0400
@@ -43,20 +43,14 @@
                                      "built-in function");
 
 octave_value_list
-octave_builtin::call (octave::tree_evaluator& tw, int nargout,
-                      const octave_value_list& args)
+octave_builtin::execute (octave::tree_evaluator& tw, int nargout,
+                         const octave_value_list& args)
 {
   octave_value_list retval;
 
   if (args.has_magic_colon ())
     error ("invalid use of colon in function argument list");
 
-  octave::unwind_protect frame;
-
-  tw.push_stack_frame (this);
-
-  frame.add_method (tw, &octave::tree_evaluator::pop_stack_frame);
-
   octave::profiler& profiler = tw.get_profiler ();
 
   octave::profiler::enter<octave_builtin> block (profiler, *this);