From ce3a4984089b8e0ce5422ca32d75ad057b008074 Mon Sep 17 00:00:00 2001 From: Steve Dower Date: Tue, 3 Mar 2020 00:04:11 +0000 Subject: [PATCH] bpo-38597: Never statically link extension initialization code on Windows (GH-18724) --- Lib/distutils/_msvccompiler.py | 60 +++---------------- Lib/distutils/tests/test_msvccompiler.py | 51 ---------------- .../2020-03-01-15-04-54.bpo-38597.MnHdYl.rst | 4 ++ PCbuild/pythoncore.vcxproj | 2 + 4 files changed, 13 insertions(+), 104 deletions(-) create mode 100644 Misc/NEWS.d/next/Windows/2020-03-01-15-04-54.bpo-38597.MnHdYl.rst diff --git a/Lib/distutils/_msvccompiler.py b/Lib/distutils/_msvccompiler.py index e8e4b717b97..03a5986d984 100644 --- a/Lib/distutils/_msvccompiler.py +++ b/Lib/distutils/_msvccompiler.py @@ -97,28 +97,11 @@ PLAT_SPEC_TO_RUNTIME = { } def _find_vcvarsall(plat_spec): + # bpo-38597: Removed vcruntime return value _, best_dir = _find_vc2017() - vcruntime = None - - if plat_spec in PLAT_SPEC_TO_RUNTIME: - vcruntime_plat = PLAT_SPEC_TO_RUNTIME[plat_spec] - else: - vcruntime_plat = 'x64' if 'amd64' in plat_spec else 'x86' - - if best_dir: - vcredist = os.path.join(best_dir, "..", "..", "redist", "MSVC", "**", - vcruntime_plat, "Microsoft.VC14*.CRT", "vcruntime140.dll") - try: - import glob - vcruntime = glob.glob(vcredist, recursive=True)[-1] - except (ImportError, OSError, LookupError): - vcruntime = None if not best_dir: best_version, best_dir = _find_vc2015() - if best_version: - vcruntime = os.path.join(best_dir, 'redist', vcruntime_plat, - "Microsoft.VC140.CRT", "vcruntime140.dll") if not best_dir: log.debug("No suitable Visual C++ version found") @@ -129,11 +112,7 @@ def _find_vcvarsall(plat_spec): log.debug("%s cannot be found", vcvarsall) return None, None - if not vcruntime or not os.path.isfile(vcruntime): - log.debug("%s cannot be found", vcruntime) - vcruntime = None - - return vcvarsall, vcruntime + return vcvarsall, None def _get_vc_env(plat_spec): if os.getenv("DISTUTILS_USE_SDK"): @@ -142,7 +121,7 @@ def _get_vc_env(plat_spec): for key, value in os.environ.items() } - vcvarsall, vcruntime = _find_vcvarsall(plat_spec) + vcvarsall, _ = _find_vcvarsall(plat_spec) if not vcvarsall: raise DistutilsPlatformError("Unable to find vcvarsall.bat") @@ -163,8 +142,6 @@ def _get_vc_env(plat_spec): if key and value } - if vcruntime: - env['py_vcruntime_redist'] = vcruntime return env def _find_exe(exe, paths=None): @@ -194,12 +171,6 @@ PLAT_TO_VCVARS = { 'win-arm64' : 'x86_arm64' } -# A set containing the DLLs that are guaranteed to be available for -# all micro versions of this Python version. Known extension -# dependencies that are not in this set will be copied to the output -# path. -_BUNDLED_DLLS = frozenset(['vcruntime140.dll']) - class MSVCCompiler(CCompiler) : """Concrete class that implements an interface to Microsoft Visual C++, as defined by the CCompiler abstract class.""" @@ -263,7 +234,6 @@ class MSVCCompiler(CCompiler) : self.rc = _find_exe("rc.exe", paths) # resource compiler self.mc = _find_exe("mc.exe", paths) # message compiler self.mt = _find_exe("mt.exe", paths) # message compiler - self._vcruntime_redist = vc_env.get('py_vcruntime_redist', '') for dir in vc_env.get('include', '').split(os.pathsep): if dir: @@ -274,13 +244,12 @@ class MSVCCompiler(CCompiler) : self.add_library_dir(dir.rstrip(os.sep)) self.preprocess_options = None - # If vcruntime_redist is available, link against it dynamically. Otherwise, - # use /MT[d] to build statically, then switch from libucrt[d].lib to ucrt[d].lib - # later to dynamically link to ucrtbase but not vcruntime. + # bpo-38597: Always compile with dynamic linking + # Future releases of Python 3.x will include all past + # versions of vcruntime*.dll for compatibility. self.compile_options = [ - '/nologo', '/Ox', '/W3', '/GL', '/DNDEBUG' + '/nologo', '/Ox', '/W3', '/GL', '/DNDEBUG', '/MD' ] - self.compile_options.append('/MD' if self._vcruntime_redist else '/MT') self.compile_options_debug = [ '/nologo', '/Od', '/MDd', '/Zi', '/W3', '/D_DEBUG' @@ -289,8 +258,6 @@ class MSVCCompiler(CCompiler) : ldflags = [ '/nologo', '/INCREMENTAL:NO', '/LTCG' ] - if not self._vcruntime_redist: - ldflags.extend(('/nodefaultlib:libucrt.lib', 'ucrt.lib')) ldflags_debug = [ '/nologo', '/INCREMENTAL:NO', '/LTCG', '/DEBUG:FULL' @@ -532,24 +499,11 @@ class MSVCCompiler(CCompiler) : try: log.debug('Executing "%s" %s', self.linker, ' '.join(ld_args)) self.spawn([self.linker] + ld_args) - self._copy_vcruntime(output_dir) except DistutilsExecError as msg: raise LinkError(msg) else: log.debug("skipping %s (up-to-date)", output_filename) - def _copy_vcruntime(self, output_dir): - vcruntime = self._vcruntime_redist - if not vcruntime or not os.path.isfile(vcruntime): - return - - if os.path.basename(vcruntime).lower() in _BUNDLED_DLLS: - return - - log.debug('Copying "%s"', vcruntime) - vcruntime = shutil.copy(vcruntime, output_dir) - os.chmod(vcruntime, stat.S_IWRITE) - def spawn(self, cmd): old_path = os.getenv('path') try: diff --git a/Lib/distutils/tests/test_msvccompiler.py b/Lib/distutils/tests/test_msvccompiler.py index 70a9c93a4e8..b518d6a78b3 100644 --- a/Lib/distutils/tests/test_msvccompiler.py +++ b/Lib/distutils/tests/test_msvccompiler.py @@ -32,57 +32,6 @@ class msvccompilerTestCase(support.TempdirManager, finally: _msvccompiler._find_vcvarsall = old_find_vcvarsall - def test_compiler_options(self): - import distutils._msvccompiler as _msvccompiler - # suppress path to vcruntime from _find_vcvarsall to - # check that /MT is added to compile options - old_find_vcvarsall = _msvccompiler._find_vcvarsall - def _find_vcvarsall(plat_spec): - return old_find_vcvarsall(plat_spec)[0], None - _msvccompiler._find_vcvarsall = _find_vcvarsall - try: - compiler = _msvccompiler.MSVCCompiler() - compiler.initialize() - - self.assertIn('/MT', compiler.compile_options) - self.assertNotIn('/MD', compiler.compile_options) - finally: - _msvccompiler._find_vcvarsall = old_find_vcvarsall - - def test_vcruntime_copy(self): - import distutils._msvccompiler as _msvccompiler - # force path to a known file - it doesn't matter - # what we copy as long as its name is not in - # _msvccompiler._BUNDLED_DLLS - old_find_vcvarsall = _msvccompiler._find_vcvarsall - def _find_vcvarsall(plat_spec): - return old_find_vcvarsall(plat_spec)[0], __file__ - _msvccompiler._find_vcvarsall = _find_vcvarsall - try: - tempdir = self.mkdtemp() - compiler = _msvccompiler.MSVCCompiler() - compiler.initialize() - compiler._copy_vcruntime(tempdir) - - self.assertTrue(os.path.isfile(os.path.join( - tempdir, os.path.basename(__file__)))) - finally: - _msvccompiler._find_vcvarsall = old_find_vcvarsall - - def test_vcruntime_skip_copy(self): - import distutils._msvccompiler as _msvccompiler - - tempdir = self.mkdtemp() - compiler = _msvccompiler.MSVCCompiler() - compiler.initialize() - dll = compiler._vcruntime_redist - self.assertTrue(os.path.isfile(dll), dll or "") - - compiler._copy_vcruntime(tempdir) - - self.assertFalse(os.path.isfile(os.path.join( - tempdir, os.path.basename(dll))), dll or "") - def test_get_vc_env_unicode(self): import distutils._msvccompiler as _msvccompiler diff --git a/Misc/NEWS.d/next/Windows/2020-03-01-15-04-54.bpo-38597.MnHdYl.rst b/Misc/NEWS.d/next/Windows/2020-03-01-15-04-54.bpo-38597.MnHdYl.rst new file mode 100644 index 00000000000..7f3a2e756c5 --- /dev/null +++ b/Misc/NEWS.d/next/Windows/2020-03-01-15-04-54.bpo-38597.MnHdYl.rst @@ -0,0 +1,4 @@ +:mod:`distutils` will no longer statically link :file:`vcruntime140.dll` +when a redistributable version is unavailable. All future releases of +CPython will include a copy of this DLL to ensure distributed extensions can +continue to load. diff --git a/PCbuild/pythoncore.vcxproj b/PCbuild/pythoncore.vcxproj index 0acf7f4a8de..ac73a912630 100644 --- a/PCbuild/pythoncore.vcxproj +++ b/PCbuild/pythoncore.vcxproj @@ -536,6 +536,8 @@ + +