bpo-34602: Avoid failures setting macOS stack resource limit (GH-14546)

Under some conditions the earlier fix for bpo-18075, "Infinite recursion
tests triggering a segfault on Mac OS X", now causes failures on macOS
when attempting to change stack limit with resource.setrlimit
resource.RLIMIT_STACK, like regrtest does when running the test suite.
The reverted change had specified a non-default stack size when linking
the python executable on macOS.  As of macOS 10.14.4, the previous
code causes a hard failure when running tests, although similar
failures had been seen under some conditions under some earlier
systems.  Reverting the change to the interpreter stack size at link
time helped for release builds but caused some tests to fail when
built --with-pydebug.  Try the opposite approach: continue to build
the interpreter with an increased stack size on macOS and remove
the failing setrlimit call in regrtest initialization.  This will
definitely avoid the resource.RLIMIT_STACK error and should have
no, or fewer, side effects.
(cherry picked from commit 5bbbc733e6cc0804f19b071944af8d4719e26ae6)

Co-authored-by: Ned Deily <nad@python.org>

diff --git a/Lib/test/libregrtest/setup.py b/Lib/test/libregrtest/setup.py
index 9a6585af9d0dd62690be2557380a6c4b5098ef49..4362e92fbda90a858bfd37ff1a2d07b94e5e75fb 100644 (file)
--- a/Lib/test/libregrtest/setup.py
+++ b/Lib/test/libregrtest/setup.py
@@ -58,22 +58,6 @@ def setup_tests(ns):
         if getattr(module, '__file__', None):
             module.__file__ = os.path.abspath(module.__file__)
 
-    # MacOSX (a.k.a. Darwin) has a default stack size that is too small
-    # for deeply recursive regular expressions.  We see this as crashes in
-    # the Python test suite when running test_re.py and test_sre.py.  The
-    # fix is to set the stack limit to 2048.
-    # This approach may also be useful for other Unixy platforms that
-    # suffer from small default stack limits.
-    if sys.platform == 'darwin':
-        try:
-            import resource
-        except ImportError:
-            pass
-        else:
-            soft, hard = resource.getrlimit(resource.RLIMIT_STACK)
-            newsoft = min(hard, max(soft, 1024*2048))
-            resource.setrlimit(resource.RLIMIT_STACK, (newsoft, hard))
-
     if ns.huntrleaks:
         unittest.BaseTestSuite._cleanup = False
 

diff --git a/Misc/NEWS.d/next/macOS/2019-07-02-01-06-47.bpo-34602.10d4wl.rst b/Misc/NEWS.d/next/macOS/2019-07-02-01-06-47.bpo-34602.10d4wl.rst
new file mode 100644 (file)
index 0000000..c50ac63
--- /dev/null
+++ b/Misc/NEWS.d/next/macOS/2019-07-02-01-06-47.bpo-34602.10d4wl.rst
@@ -0,0 +1,4 @@
+Avoid test suite failures on macOS by no longer calling resource.setrlimit
+to increase the process stack size limit at runtime.  The runtime change is
+no longer needed since the interpreter is being built with a larger default
+stack size.

diff --git a/configure b/configure
index bc6894ec6fced45f6a76a70dd0b6ada30ebf0f2d..2db11e6e86676fe4f2c770907298652bc9038082 100755 (executable)
--- a/configure
+++ b/configure
@@ -9541,6 +9541,12 @@ then
        # -u libsys_s pulls in all symbols in libsys
        Darwin/*)
                LINKFORSHARED="$extra_undefs -framework CoreFoundation"
+
+               # Issue #18075: the default maximum stack size (8MBytes) is too
+               # small for the default recursion limit. Increase the stack size
+               # to ensure that tests don't crash
+               LINKFORSHARED="-Wl,-stack_size,1000000 $LINKFORSHARED"
+
                if test "$enable_framework"
                then
                        LINKFORSHARED="$LINKFORSHARED "'$(PYTHONFRAMEWORKDIR)/Versions/$(VERSION)/$(PYTHONFRAMEWORK)'

diff --git a/configure.ac b/configure.ac
index 97745aa11240162f6d7ff7f3b808c0e8ce8f9605..e5fb7e7b0b136e119fa87fb73de0df41d4049d8d 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -2708,6 +2708,12 @@ then
        # -u libsys_s pulls in all symbols in libsys
        Darwin/*)
                LINKFORSHARED="$extra_undefs -framework CoreFoundation"
+
+               # Issue #18075: the default maximum stack size (8MBytes) is too
+               # small for the default recursion limit. Increase the stack size
+               # to ensure that tests don't crash
+               LINKFORSHARED="-Wl,-stack_size,1000000 $LINKFORSHARED"
+
                if test "$enable_framework"
                then
                        LINKFORSHARED="$LINKFORSHARED "'$(PYTHONFRAMEWORKDIR)/Versions/$(VERSION)/$(PYTHONFRAMEWORK)'