From b6484282f85bf7f11451b2441599c241d302ad9d Mon Sep 17 00:00:00 2001
From: Raul Tambre <raul@tambre.ee>
Date: Sat, 4 May 2019 15:48:17 -0400
Subject: [PATCH] Fix incorrect use of 'is' operator for comparison in
 python/lib/gdb/command/prompt.py

The 'is' operator is not meant to be used for comparisons. It currently working
is an implementation detail of CPython.  CPython 3.8 has added a SyntaxWarning
for this.

diff --git a/gdb/python/lib/gdb/command/prompt.py b/gdb/python/lib/gdb/command/prompt.py
index 3d662a7..04b9e49 100644
--- a/gdb/python/lib/gdb/command/prompt.py
+++ b/gdb/python/lib/gdb/command/prompt.py
@@ -45,7 +45,7 @@ The currently defined substitutions are:
         self.hook_set = False
 
     def get_show_string (self, pvalue):
-        if self.value is not '':
+        if self.value:
            return "The extended prompt is: " + self.value
         else:
            return "The extended prompt is not set."
@@ -57,7 +57,7 @@ The currently defined substitutions are:
         return ""
 
     def before_prompt_hook(self, current):
-        if self.value is not '':
+        if self.value:
             return gdb.prompt.substitute_prompt(self.value)
         else:
             return None

From d9c4ba536c522b8dc2194d4100270a159be7894a Mon Sep 17 00:00:00 2001
From: Sergio Durigan Junior <sergiodj@redhat.com>
Date: Sun, 25 Aug 2019 12:10:35 -0400
Subject: [PATCH] Use raw strings on gdb.python/py-xmethods.exp (and fix Python
 3.8's "SyntaxWarning: invalid escape sequence")

The way unrecognized escape sequences are handled has changed in
Python 3.8: users now see a SyntaxWarning message, which will
eventually become a SyntaxError in future versions of Python:

  (gdb) source /blabla/gdb.python/py-xmethods/py-xmethods.py
  /blabla/gdb.python/py-xmethods/py-xmethods.py:204: SyntaxWarning: invalid escape seque
  nce \+
    'operator\+',
  /blabla/gdb.python/py-xmethods/py-xmethods.py:211: SyntaxWarning: invalid escape seque
  nce \+
    'operator\+\+',

One of our testcases, gdb.python/py-xmethods.exp, contains strings in
the form of "operator\+".  This is not recognized by Python, but is
still needed by the testsuite to work properly.  The solution is
simple: we just have to make sure these strings are marked as
raw (i.e, r"").  This is what this patch does.  I took the opportunity
to also convert other strings to raw, which, in two cases, allowed the
removal of an extra backslash.

I tested this using Python 3.7 and Python 3.8, and everything works
fine.

I think I could push this as obvious, but decided to send it to
gdb-patches just in case.

gdb/testsuite/ChangeLog:
2019-08-26  Sergio Durigan Junior  <sergiodj@redhat.com>

	* gdb.python/py-xmethods.exp: Use raw strings when passing
	arguments to SimpleXMethodMatcher.

diff --git a/gdb/testsuite/gdb.python/py-xmethods.py b/gdb/testsuite/gdb.python/py-xmethods.py
index 587842d7360..cea48b80d8c 100644
--- a/gdb/testsuite/gdb.python/py-xmethods.py
+++ b/gdb/testsuite/gdb.python/py-xmethods.py
@@ -199,34 +199,34 @@ def match(self, class_type, method_name):
 
 
 global_dm_list = [
-    SimpleXMethodMatcher('A_plus_A',
-                         '^dop::A$',
-                         'operator\+',
+    SimpleXMethodMatcher(r'A_plus_A',
+                         r'^dop::A$',
+                         r'operator\+',
                          A_plus_A,
                          # This is a replacement, hence match the arg type
                          # exactly!
                          type_A.const().reference()),
-    SimpleXMethodMatcher('plus_plus_A',
-                         '^dop::A$',
-                         'operator\+\+',
+    SimpleXMethodMatcher(r'plus_plus_A',
+                         r'^dop::A$',
+                         r'operator\+\+',
                          plus_plus_A),
-    SimpleXMethodMatcher('A_geta',
-                         '^dop::A$',
-                         '^geta$',
+    SimpleXMethodMatcher(r'A_geta',
+                         r'^dop::A$',
+                         r'^geta$',
                          A_geta),
-    SimpleXMethodMatcher('A_getarrayind',
-                         '^dop::A$',
-                         '^getarrayind$',
+    SimpleXMethodMatcher(r'A_getarrayind',
+                         r'^dop::A$',
+                         r'^getarrayind$',
                          A_getarrayind,
                          type_int),
-    SimpleXMethodMatcher('A_indexoper',
-                         '^dop::A$',
-                         'operator\\[\\]',
+    SimpleXMethodMatcher(r'A_indexoper',
+                         r'^dop::A$',
+                         r'operator\[\]',
                          A_indexoper,
                          type_int),
-    SimpleXMethodMatcher('B_indexoper',
-                         '^dop::B$',
-                         'operator\\[\\]',
+    SimpleXMethodMatcher(r'B_indexoper',
+                         r'^dop::B$',
+                         r'operator\[\]',
                          B_indexoper,
                          type_int)
 ]