[Python-checkins] bpo-38118: Ignore Valgrind false alarm in PyUnicode_Decode() (GH-16651)

[Miss Islington (bot)]

https://github.com/python/cpython/commit/98043b4fcd80bdfa8cc2be1730fa2a4cf4950958
commit: 98043b4fcd80bdfa8cc2be1730fa2a4cf4950958
branch: 3.7
author: Miss Islington (bot) <31488909+miss-islington at users.noreply.github.com>
committer: GitHub <noreply at github.com>
date: 2019-10-08T06:56:08-07:00
summary:

bpo-38118: Ignore Valgrind false alarm in PyUnicode_Decode() (GH-16651)


Valgrind emits "Conditional jump or move depends on uninitialised
value(s)" false alarms on GCC builtin strcmp() function. The GCC code
is correct.

Valgrind bug: https://bugs.kde.org/show_bug.cgi?id=264936
(cherry picked from commit 03ab6b4fc6f59a4452756e7a3a46310ce30ec4b2)

Co-authored-by: Victor Stinner <vstinner at python.org>

files:
A Misc/NEWS.d/next/Tools-Demos/2019-10-08-15-07-52.bpo-38118.pIZD6H.rst
M Misc/valgrind-python.supp

diff --git a/Misc/NEWS.d/next/Tools-Demos/2019-10-08-15-07-52.bpo-38118.pIZD6H.rst b/Misc/NEWS.d/next/Tools-Demos/2019-10-08-15-07-52.bpo-38118.pIZD6H.rst
new file mode 100644
index 0000000000000..13adadb0b8f7a
--- /dev/null
+++ b/Misc/NEWS.d/next/Tools-Demos/2019-10-08-15-07-52.bpo-38118.pIZD6H.rst
@@ -0,0 +1,2 @@
+Update Valgrind suppression file to ignore a false alarm in
+:c:func:`PyUnicode_Decode` when using GCC builtin strcmp().
diff --git a/Misc/valgrind-python.supp b/Misc/valgrind-python.supp
index bc8f77f261a80..38a5ea3cd2b82 100644
--- a/Misc/valgrind-python.supp
+++ b/Misc/valgrind-python.supp
@@ -283,6 +283,17 @@
    fun:rl_initialize
 }
 
+# Valgrind emits "Conditional jump or move depends on uninitialised value(s)"
+# false alarms on GCC builtin strcmp() function. The GCC code is correct.
+#
+# Valgrind bug: https://bugs.kde.org/show_bug.cgi?id=264936
+{
+   bpo-38118: Valgrind emits false alarm on GCC builtin strcmp()
+   Memcheck:Cond
+   fun:PyUnicode_Decode
+}
+
+
 ###
 ### These occur from somewhere within the SSL, when running
 ###  test_socket_sll.  They are too general to leave on by default.