From 9b7c74ca32d1bec7128d550a9ab1b2ddc7046287 Mon Sep 17 00:00:00 2001 From: Marcel Plch Date: Fri, 15 Jun 2018 17:56:24 +0200 Subject: [PATCH] bpo-32962: Fix test_gdb failure in debug build with -mcet -fcf-protection -O0 (#6754) When Python is built with the intel control-flow protection flags, -mcet -fcf-protection, gdb is not able to read the stack without actually jumping inside the function. This means an extra 'next' command is required to make the $pc (program counter) enter the function and make the stack of the function exposed to gdb. --- Lib/test/test_gdb.py | 11 +++++++++-- .../Tests/2018-05-10-16-59-15.bpo-32962.S-rcIN.rst | 1 + 2 files changed, 10 insertions(+), 2 deletions(-) create mode 100644 Misc/NEWS.d/next/Tests/2018-05-10-16-59-15.bpo-32962.S-rcIN.rst diff --git a/Lib/test/test_gdb.py b/Lib/test/test_gdb.py index 9e0eaea8c8f..d341a17f1fe 100644 --- a/Lib/test/test_gdb.py +++ b/Lib/test/test_gdb.py @@ -162,7 +162,11 @@ class DebuggerTests(unittest.TestCase): commands += ['set print entry-values no'] if cmds_after_breakpoint: - commands += cmds_after_breakpoint + # bpo-32962: When Python is compiled with -mcet -fcf-protection, + # arguments are unusable before running the first instruction + # of the function entry point. The 'next' command makes the + # required first step. + commands += ['next'] + cmds_after_breakpoint else: commands += ['backtrace'] @@ -847,9 +851,12 @@ id(42) id("first break point") l = MyList() ''') + # bpo-32962: same case as in get_stack_trace(): + # we need an additional 'next' command in order to read + # arguments of the innermost function of the call stack. # Verify with "py-bt": gdb_output = self.get_stack_trace(cmd, - cmds_after_breakpoint=['break wrapper_call', 'continue', 'py-bt']) + cmds_after_breakpoint=['break wrapper_call', 'continue', 'next', 'py-bt']) self.assertRegex(gdb_output, r"