bpo-29673: fix gdb scripts pystack and pystackv (pythonGH-6126)

(cherry picked from commit 3a9ccee)

Co-authored-by: Marcel Plch <gmarcel.plch@gmail.com>

Author: Marcel Plch

Misc/ACKS

@@ -1221,6 +1221,7 @@ Zero Piraeus
 Antoine Pitrou
 Jean-François Piéronne
 Oleg Plakhotnyuk
+Marcel Plch
 Remi Pointel
 Jon Poler
 Ariel Poliak

Misc/NEWS.d/next/Tools-Demos/2018-03-16-17-25-05.bpo-29673.m8QtaW.rst

@@ -0,0 +1 @@
+Fix pystackv and pystack gdbinit macros.

Misc/gdbinit

@@ -36,8 +36,8 @@ define pylocals
     set $_i = 0
     while $_i < f->f_code->co_nlocals
 	if f->f_localsplus + $_i != 0
-	    set $_names = co->co_varnames
-	    set $_name = _PyUnicode_AsString(PyTuple_GetItem($_names, $_i))
+	    set $_names = f->f_code->co_varnames
+	    set $_name = PyUnicode_AsUTF8(PyTuple_GetItem($_names, $_i))
 	    printf "%s:\n", $_name
             pyo f->f_localsplus[$_i]
 	end
@@ -76,8 +76,8 @@ define pyframev
 end
 
 define pyframe
-    set $__fn = _PyUnicode_AsString(co->co_filename)
-    set $__n = _PyUnicode_AsString(co->co_name)
+    set $__fn = PyUnicode_AsUTF8(f->f_code->co_filename)
+    set $__n = PyUnicode_AsUTF8(f->f_code->co_name)
     printf "%s (", $__fn
     lineno
     printf "): %s\n", $__n
@@ -102,7 +102,7 @@ end
 #end
 
 define printframe
-    if $pc > PyEval_EvalFrameEx && $pc < PyEval_EvalCodeEx
+    if $pc > PyEval_EvalFrameEx && $pc < _PyEval_EvalFrameDefault
 	pyframe
     else
         frame
@@ -129,7 +129,7 @@ end
 # print the entire Python call stack
 define pystack
     while $pc < Py_Main || $pc > Py_GetArgcArgv
-        if $pc > PyEval_EvalFrameEx && $pc < PyEval_EvalCodeEx
+        if $pc > PyEval_EvalFrameEx && $pc < _PyEval_EvalFrameDefault
 	    pyframe
         end
         up-silently 1
@@ -140,7 +140,7 @@ end
 # print the entire Python call stack - verbose mode
 define pystackv
     while $pc < Py_Main || $pc > Py_GetArgcArgv
-        if $pc > PyEval_EvalFrameEx && $pc < PyEval_EvalCodeEx
+        if $pc > PyEval_EvalFrameEx && $pc < _PyEval_EvalFrameDefault
 	    pyframev
         end
         up-silently 1

Python/ceval.c

@@ -3888,7 +3888,7 @@ too_many_positional(PyCodeObject *co, Py_ssize_t given, Py_ssize_t defcount,
 }
 
 /* This is gonna seem *real weird*, but if you put some other code between
-   PyEval_EvalFrame() and PyEval_EvalCodeEx() you will need to adjust
+   PyEval_EvalFrame() and _PyEval_EvalFrameDefault() you will need to adjust
    the test in the if statements in Misc/gdbinit (pystack and pystackv). */
 
 static PyObject *