From a3febe3cba14b89885f42ca2f0224096a52885f6 Mon Sep 17 00:00:00 2001 From: Antoine Pitrou Date: Mon, 23 Apr 2018 13:19:42 +0200 Subject: [PATCH] bpo-33329: Fix multiprocessing regression on newer glibcs Starting with glibc 2.27.9000-xxx, sigaddset() can return EINVAL for some reserved signal numbers between 1 and NSIG. The `range(1, NSIG)` idiom is commonly used to select all signals for blocking with `pthread_sigmask`. So we ignore the sigaddset() return value until we expose sigfillset() to provide a better idiom. --- .../next/Library/2018-04-23-13-21-39.bpo-33329.lQ-Eod.rst | 1 + Modules/signalmodule.c | 14 ++++++++------ 2 files changed, 9 insertions(+), 6 deletions(-) create mode 100644 Misc/NEWS.d/next/Library/2018-04-23-13-21-39.bpo-33329.lQ-Eod.rst diff --git a/Misc/NEWS.d/next/Library/2018-04-23-13-21-39.bpo-33329.lQ-Eod.rst b/Misc/NEWS.d/next/Library/2018-04-23-13-21-39.bpo-33329.lQ-Eod.rst new file mode 100644 index 000000000000..d1a4e56d04b9 --- /dev/null +++ b/Misc/NEWS.d/next/Library/2018-04-23-13-21-39.bpo-33329.lQ-Eod.rst @@ -0,0 +1 @@ +Fix multiprocessing regression on newer glibcs diff --git a/Modules/signalmodule.c b/Modules/signalmodule.c index 791616014384..35fd87e2d1e7 100644 --- a/Modules/signalmodule.c +++ b/Modules/signalmodule.c @@ -819,7 +819,6 @@ iterable_to_sigset(PyObject *iterable, sigset_t *mask) int result = -1; PyObject *iterator, *item; long signum; - int err; sigemptyset(mask); @@ -841,11 +840,14 @@ iterable_to_sigset(PyObject *iterable, sigset_t *mask) Py_DECREF(item); if (signum == -1 && PyErr_Occurred()) goto error; - if (0 < signum && signum < NSIG) - err = sigaddset(mask, (int)signum); - else - err = 1; - if (err) { + if (0 < signum && signum < NSIG) { + /* bpo-33329: ignore sigaddset() return value as it can fail + * for some reserved signals, but we want the `range(1, NSIG)` + * idiom to allow selecting all valid signals. + */ + (void) sigaddset(mask, (int)signum); + } + else { PyErr_Format(PyExc_ValueError, "signal number %ld out of range", signum); goto error;