From 9de38bba372b1415c078d84246297a91b2055024 Mon Sep 17 00:00:00 2001
From: Lumir Balhar <lbalhar@redhat.com>
Date: Thu, 15 Oct 2020 07:44:08 +0200
Subject: [PATCH 01/24] Mark distutils.sysconfig as deprecated

---
 Lib/distutils/sysconfig.py | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/Lib/distutils/sysconfig.py b/Lib/distutils/sysconfig.py
index 37feae5df72c93..da99f42a1d8bb3 100644
--- a/Lib/distutils/sysconfig.py
+++ b/Lib/distutils/sysconfig.py
@@ -13,9 +13,16 @@
 import os
 import re
 import sys
+import warnings
 
 from .errors import DistutilsPlatformError
 
+warnings.warn(
+    'the distutils.sysconfig module is deprecated, use sysconfig instead',
+    DeprecationWarning,
+    stacklevel=2
+)
+
 # These are needed in a couple of spots, so just compute them once.
 PREFIX = os.path.normpath(sys.prefix)
 EXEC_PREFIX = os.path.normpath(sys.exec_prefix)

From 2f73368cbd28dceb01f6bb0e0f5fd898d93fddb9 Mon Sep 17 00:00:00 2001
From: Lumir Balhar <lbalhar@redhat.com>
Date: Thu, 15 Oct 2020 08:03:33 +0200
Subject: [PATCH 02/24] Import global paths from sysconfig module

---
 Lib/distutils/sysconfig.py | 11 +++++------
 1 file changed, 5 insertions(+), 6 deletions(-)

diff --git a/Lib/distutils/sysconfig.py b/Lib/distutils/sysconfig.py
index da99f42a1d8bb3..e2858a849b846e 100644
--- a/Lib/distutils/sysconfig.py
+++ b/Lib/distutils/sysconfig.py
@@ -17,18 +17,17 @@
 
 from .errors import DistutilsPlatformError
 
+from sysconfig import _PREFIX as PREFIX
+from sysconfig import _BASE_PREFIX as BASE_PREFIX
+from sysconfig import _EXEC_PREFIX as EXEC_PREFIX
+from sysconfig import _BASE_EXEC_PREFIX as BASE_EXEC_PREFIX
+
 warnings.warn(
     'the distutils.sysconfig module is deprecated, use sysconfig instead',
     DeprecationWarning,
     stacklevel=2
 )
 
-# These are needed in a couple of spots, so just compute them once.
-PREFIX = os.path.normpath(sys.prefix)
-EXEC_PREFIX = os.path.normpath(sys.exec_prefix)
-BASE_PREFIX = os.path.normpath(sys.base_prefix)
-BASE_EXEC_PREFIX = os.path.normpath(sys.base_exec_prefix)
-
 # Path to the base directory of the project. On Windows the binary may
 # live in project/PCbuild/win32 or project/PCbuild/amd64.
 # set for cross builds

From 43d810eef6837fbf1957cc519ca99127ddc5418c Mon Sep 17 00:00:00 2001
From: Lumir Balhar <lbalhar@redhat.com>
Date: Thu, 15 Oct 2020 09:35:11 +0200
Subject: [PATCH 03/24] Move some similar functions from distutils.sysconfig ->
 sysconfig

---
 Lib/distutils/sysconfig.py | 260 +++----------------------------------
 Lib/sysconfig.py           |  85 +++++++++++-
 2 files changed, 99 insertions(+), 246 deletions(-)

diff --git a/Lib/distutils/sysconfig.py b/Lib/distutils/sysconfig.py
index e2858a849b846e..60112ba5f62363 100644
--- a/Lib/distutils/sysconfig.py
+++ b/Lib/distutils/sysconfig.py
@@ -21,6 +21,17 @@
 from sysconfig import _BASE_PREFIX as BASE_PREFIX
 from sysconfig import _EXEC_PREFIX as EXEC_PREFIX
 from sysconfig import _BASE_EXEC_PREFIX as BASE_EXEC_PREFIX
+from sysconfig import parse_config_h as sysconfig_parse_config_h
+from sysconfig import _parse_makefile as sysconfig_parse_makefile
+
+from sysconfig import _is_python_source_dir
+from sysconfig import _sys_home
+
+from sysconfig import expand_makefile_vars
+from sysconfig import get_config_var
+from sysconfig import get_python_version
+from sysconfig import get_python_lib
+
 
 warnings.warn(
     'the distutils.sysconfig module is deprecated, use sysconfig instead',
@@ -28,6 +39,16 @@
     stacklevel=2
 )
 
+
+# Following functions are the same as in sysconfig but with different API
+def parse_config_h(fp, g=None):
+    return sysconfig_parse_config_h(fp, vars=g)
+
+
+def parse_makefile(fn, g=None):
+    return sysconfig_parse_makefile(fn, vars=g)
+
+
 # Path to the base directory of the project. On Windows the binary may
 # live in project/PCbuild/win32 or project/PCbuild/amd64.
 # set for cross builds
@@ -42,17 +63,6 @@
         project_base = os.getcwd()
 
 
-# python_build: (Boolean) if true, we're either building Python or
-# building an extension with an un-installed Python, so we use
-# different (hard-wired) directories.
-def _is_python_source_dir(d):
-    for fn in ("Setup", "Setup.local"):
-        if os.path.isfile(os.path.join(d, "Modules", fn)):
-            return True
-    return False
-
-_sys_home = getattr(sys, '_home', None)
-
 if os.name == 'nt':
     def _fix_pcbuild(d):
         if d and os.path.normcase(d).startswith(
@@ -82,13 +92,6 @@ def _python_build():
     # this attribute, which is fine.
     pass
 
-def get_python_version():
-    """Return a string containing the major and minor Python version,
-    leaving off the patchlevel.  Sample return values could be '1.5'
-    or '2.2'.
-    """
-    return '%d.%d' % sys.version_info[:2]
-
 
 def get_python_inc(plat_specific=0, prefix=None):
     """Return the directory containing installed Python header files.
@@ -130,52 +133,6 @@ def get_python_inc(plat_specific=0, prefix=None):
             "on platform '%s'" % os.name)
 
 
-def get_python_lib(plat_specific=0, standard_lib=0, prefix=None):
-    """Return the directory containing the Python library (standard or
-    site additions).
-
-    If 'plat_specific' is true, return the directory containing
-    platform-specific modules, i.e. any module from a non-pure-Python
-    module distribution; otherwise, return the platform-shared library
-    directory.  If 'standard_lib' is true, return the directory
-    containing standard Python library modules; otherwise, return the
-    directory for site-specific modules.
-
-    If 'prefix' is supplied, use it instead of sys.base_prefix or
-    sys.base_exec_prefix -- i.e., ignore 'plat_specific'.
-    """
-    if prefix is None:
-        if standard_lib:
-            prefix = plat_specific and BASE_EXEC_PREFIX or BASE_PREFIX
-        else:
-            prefix = plat_specific and EXEC_PREFIX or PREFIX
-
-    if os.name == "posix":
-        if plat_specific or standard_lib:
-            # Platform-specific modules (any module from a non-pure-Python
-            # module distribution) or standard Python library modules.
-            libdir = sys.platlibdir
-        else:
-            # Pure Python
-            libdir = "lib"
-        libpython = os.path.join(prefix, libdir,
-                                 "python" + get_python_version())
-        if standard_lib:
-            return libpython
-        else:
-            return os.path.join(libpython, "site-packages")
-    elif os.name == "nt":
-        if standard_lib:
-            return os.path.join(prefix, "Lib")
-        else:
-            return os.path.join(prefix, "Lib", "site-packages")
-    else:
-        raise DistutilsPlatformError(
-            "I don't know where Python installs its library "
-            "on platform '%s'" % os.name)
-
-
-
 def customize_compiler(compiler):
     """Do any platform-specific customization of a CCompiler instance.
 
@@ -273,172 +230,6 @@ def get_makefile_filename():
     return os.path.join(lib_dir, config_file, 'Makefile')
 
 
-def parse_config_h(fp, g=None):
-    """Parse a config.h-style file.
-
-    A dictionary containing name/value pairs is returned.  If an
-    optional dictionary is passed in as the second argument, it is
-    used instead of a new dictionary.
-    """
-    if g is None:
-        g = {}
-    define_rx = re.compile("#define ([A-Z][A-Za-z0-9_]+) (.*)\n")
-    undef_rx = re.compile("/[*] #undef ([A-Z][A-Za-z0-9_]+) [*]/\n")
-    #
-    while True:
-        line = fp.readline()
-        if not line:
-            break
-        m = define_rx.match(line)
-        if m:
-            n, v = m.group(1, 2)
-            try: v = int(v)
-            except ValueError: pass
-            g[n] = v
-        else:
-            m = undef_rx.match(line)
-            if m:
-                g[m.group(1)] = 0
-    return g
-
-
-# Regexes needed for parsing Makefile (and similar syntaxes,
-# like old-style Setup files).
-_variable_rx = re.compile(r"([a-zA-Z][a-zA-Z0-9_]+)\s*=\s*(.*)")
-_findvar1_rx = re.compile(r"\$\(([A-Za-z][A-Za-z0-9_]*)\)")
-_findvar2_rx = re.compile(r"\${([A-Za-z][A-Za-z0-9_]*)}")
-
-def parse_makefile(fn, g=None):
-    """Parse a Makefile-style file.
-
-    A dictionary containing name/value pairs is returned.  If an
-    optional dictionary is passed in as the second argument, it is
-    used instead of a new dictionary.
-    """
-    from distutils.text_file import TextFile
-    fp = TextFile(fn, strip_comments=1, skip_blanks=1, join_lines=1, errors="surrogateescape")
-
-    if g is None:
-        g = {}
-    done = {}
-    notdone = {}
-
-    while True:
-        line = fp.readline()
-        if line is None: # eof
-            break
-        m = _variable_rx.match(line)
-        if m:
-            n, v = m.group(1, 2)
-            v = v.strip()
-            # `$$' is a literal `$' in make
-            tmpv = v.replace('$$', '')
-
-            if "$" in tmpv:
-                notdone[n] = v
-            else:
-                try:
-                    v = int(v)
-                except ValueError:
-                    # insert literal `$'
-                    done[n] = v.replace('$$', '$')
-                else:
-                    done[n] = v
-
-    # Variables with a 'PY_' prefix in the makefile. These need to
-    # be made available without that prefix through sysconfig.
-    # Special care is needed to ensure that variable expansion works, even
-    # if the expansion uses the name without a prefix.
-    renamed_variables = ('CFLAGS', 'LDFLAGS', 'CPPFLAGS')
-
-    # do variable interpolation here
-    while notdone:
-        for name in list(notdone):
-            value = notdone[name]
-            m = _findvar1_rx.search(value) or _findvar2_rx.search(value)
-            if m:
-                n = m.group(1)
-                found = True
-                if n in done:
-                    item = str(done[n])
-                elif n in notdone:
-                    # get it on a subsequent round
-                    found = False
-                elif n in os.environ:
-                    # do it like make: fall back to environment
-                    item = os.environ[n]
-
-                elif n in renamed_variables:
-                    if name.startswith('PY_') and name[3:] in renamed_variables:
-                        item = ""
-
-                    elif 'PY_' + n in notdone:
-                        found = False
-
-                    else:
-                        item = str(done['PY_' + n])
-                else:
-                    done[n] = item = ""
-                if found:
-                    after = value[m.end():]
-                    value = value[:m.start()] + item + after
-                    if "$" in after:
-                        notdone[name] = value
-                    else:
-                        try: value = int(value)
-                        except ValueError:
-                            done[name] = value.strip()
-                        else:
-                            done[name] = value
-                        del notdone[name]
-
-                        if name.startswith('PY_') \
-                            and name[3:] in renamed_variables:
-
-                            name = name[3:]
-                            if name not in done:
-                                done[name] = value
-            else:
-                # bogus variable reference; just drop it since we can't deal
-                del notdone[name]
-
-    fp.close()
-
-    # strip spurious spaces
-    for k, v in done.items():
-        if isinstance(v, str):
-            done[k] = v.strip()
-
-    # save the results in the global dictionary
-    g.update(done)
-    return g
-
-
-def expand_makefile_vars(s, vars):
-    """Expand Makefile-style variables -- "${foo}" or "$(foo)" -- in
-    'string' according to 'vars' (a dictionary mapping variable names to
-    values).  Variables not present in 'vars' are silently expanded to the
-    empty string.  The variable values in 'vars' should not contain further
-    variable expansions; if 'vars' is the output of 'parse_makefile()',
-    you're fine.  Returns a variable-expanded version of 's'.
-    """
-
-    # This algorithm does multiple expansion, so if vars['foo'] contains
-    # "${bar}", it will expand ${foo} to ${bar}, and then expand
-    # ${bar}... and so forth.  This is fine as long as 'vars' comes from
-    # 'parse_makefile()', which takes care of such expansions eagerly,
-    # according to make's variable expansion semantics.
-
-    while True:
-        m = _findvar1_rx.search(s) or _findvar2_rx.search(s)
-        if m:
-            (beg, end) = m.span()
-            s = s[0:beg] + vars.get(m.group(1)) + s[end:]
-        else:
-            break
-    return s
-
-
 _config_vars = None
 
 def _init_posix():
@@ -550,12 +341,3 @@ def get_config_vars(*args):
     else:
         return _config_vars
 
-def get_config_var(name):
-    """Return the value of a single variable using the dictionary
-    returned by 'get_config_vars()'.  Equivalent to
-    get_config_vars().get(name)
-    """
-    if name == 'SO':
-        import warnings
-        warnings.warn('SO is deprecated, use EXT_SUFFIX', DeprecationWarning, 2)
-    return get_config_vars().get(name)
diff --git a/Lib/sysconfig.py b/Lib/sysconfig.py
index d056d2c3381608..f42adb33d2a254 100644
--- a/Lib/sysconfig.py
+++ b/Lib/sysconfig.py
@@ -1,8 +1,10 @@
 """Access to Python's configuration information."""
 
 import os
+import re
 import sys
 from os.path import pardir, realpath
+from distutils.errors import DistutilsPlatformError
 
 __all__ = [
     'get_config_h_filename',
@@ -130,6 +132,12 @@ def joinuser(*args):
 _CONFIG_VARS = None
 _USER_BASE = None
 
+# Regexes needed for parsing Makefile (and similar syntaxes,
+# like old-style Setup files).
+_variable_rx = re.compile(r"([a-zA-Z][a-zA-Z0-9_]+)\s*=\s*(.*)")
+_findvar1_rx = re.compile(r"\$\(([A-Za-z][A-Za-z0-9_]*)\)")
+_findvar2_rx = re.compile(r"\${([A-Za-z][A-Za-z0-9_]*)}")
+
 
 def _safe_realpath(path):
     try:
@@ -222,13 +230,6 @@ def _parse_makefile(filename, vars=None):
     optional dictionary is passed in as the second argument, it is
     used instead of a new dictionary.
     """
-    # Regexes needed for parsing Makefile (and similar syntaxes,
-    # like old-style Setup files).
-    import re
-    _variable_rx = re.compile(r"([a-zA-Z][a-zA-Z0-9_]+)\s*=\s*(.*)")
-    _findvar1_rx = re.compile(r"\$\(([A-Za-z][A-Za-z0-9_]*)\)")
-    _findvar2_rx = re.compile(r"\${([A-Za-z][A-Za-z0-9_]*)}")
-
     if vars is None:
         vars = {}
     done = {}
@@ -712,6 +713,76 @@ def get_python_version():
     return _PY_VERSION_SHORT
 
 
+def get_python_lib(plat_specific=0, standard_lib=0, prefix=None):
+    """Return the directory containing the Python library (standard or
+    site additions).
+
+    If 'plat_specific' is true, return the directory containing
+    platform-specific modules, i.e. any module from a non-pure-Python
+    module distribution; otherwise, return the platform-shared library
+    directory.  If 'standard_lib' is true, return the directory
+    containing standard Python library modules; otherwise, return the
+    directory for site-specific modules.
+
+    If 'prefix' is supplied, use it instead of sys.base_prefix or
+    sys.base_exec_prefix -- i.e., ignore 'plat_specific'.
+    """
+    if prefix is None:
+        if standard_lib:
+            prefix = plat_specific and _BASE_EXEC_PREFIX or _BASE_PREFIX
+        else:
+            prefix = plat_specific and _EXEC_PREFIX or _PREFIX
+
+    if os.name == "posix":
+        if plat_specific or standard_lib:
+            # Platform-specific modules (any module from a non-pure-Python
+            # module distribution) or standard Python library modules.
+            libdir = sys.platlibdir
+        else:
+            # Pure Python
+            libdir = "lib"
+        libpython = os.path.join(prefix, libdir,
+                                 "python" + get_python_version())
+        if standard_lib:
+            return libpython
+        else:
+            return os.path.join(libpython, "site-packages")
+    elif os.name == "nt":
+        if standard_lib:
+            return os.path.join(prefix, "Lib")
+        else:
+            return os.path.join(prefix, "Lib", "site-packages")
+    else:
+        raise DistutilsPlatformError(
+            "I don't know where Python installs its library "
+            "on platform '%s'" % os.name)
+
+
+def expand_makefile_vars(s, vars):
+    """Expand Makefile-style variables -- "${foo}" or "$(foo)" -- in
+    'string' according to 'vars' (a dictionary mapping variable names to
+    values).  Variables not present in 'vars' are silently expanded to the
+    empty string.  The variable values in 'vars' should not contain further
+    variable expansions; if 'vars' is the output of 'parse_makefile()',
+    you're fine.  Returns a variable-expanded version of 's'.
+    """
+
+    # This algorithm does multiple expansion, so if vars['foo'] contains
+    # "${bar}", it will expand ${foo} to ${bar}, and then expand
+    # ${bar}... and so forth.  This is fine as long as 'vars' comes from
+    # 'parse_makefile()', which takes care of such expansions eagerly,
+    # according to make's variable expansion semantics.
+
+    while True:
+        m = _findvar1_rx.search(s) or _findvar2_rx.search(s)
+        if m:
+            (beg, end) = m.span()
+            s = s[0:beg] + vars.get(m.group(1)) + s[end:]
+        else:
+            break
+    return s
+
+
 def _print_dict(title, data):
     for index, (key, value) in enumerate(sorted(data.items())):
         if index == 0:

From 2ca4dfd87f9d100797136cb756adea88f20495b4 Mon Sep 17 00:00:00 2001
From: Lumir Balhar <lbalhar@redhat.com>
Date: Thu, 15 Oct 2020 10:53:10 +0200
Subject: [PATCH 04/24] Move the rest of global variables

---
 Lib/distutils/sysconfig.py | 96 +++++---------------------------------
 Lib/sysconfig.py           | 40 ++++++++++++++++
 2 files changed, 51 insertions(+), 85 deletions(-)

diff --git a/Lib/distutils/sysconfig.py b/Lib/distutils/sysconfig.py
index 60112ba5f62363..dc442d4e58b96f 100644
--- a/Lib/distutils/sysconfig.py
+++ b/Lib/distutils/sysconfig.py
@@ -15,23 +15,33 @@
 import sys
 import warnings
 
+from functools import partial
+
 from .errors import DistutilsPlatformError
 
 from sysconfig import _PREFIX as PREFIX
 from sysconfig import _BASE_PREFIX as BASE_PREFIX
 from sysconfig import _EXEC_PREFIX as EXEC_PREFIX
 from sysconfig import _BASE_EXEC_PREFIX as BASE_EXEC_PREFIX
+from sysconfig import _PROJECT_BASE as project_base
+from sysconfig import _PYTHON_BUILD as python_build
+from sysconfig import _CONFIG_VARS as _config_vars
 from sysconfig import parse_config_h as sysconfig_parse_config_h
 from sysconfig import _parse_makefile as sysconfig_parse_makefile
 
 from sysconfig import _is_python_source_dir
 from sysconfig import _sys_home
 
+from sysconfig import build_flags
 from sysconfig import expand_makefile_vars
+from sysconfig import is_python_build
 from sysconfig import get_config_var
+from sysconfig import get_python_inc
 from sysconfig import get_python_version
 from sysconfig import get_python_lib
 
+if os.name == "nt":
+    from sysconfig import _fix_pcbuild
 
 warnings.warn(
     'the distutils.sysconfig module is deprecated, use sysconfig instead',
@@ -48,89 +58,7 @@ def parse_config_h(fp, g=None):
 def parse_makefile(fn, g=None):
     return sysconfig_parse_makefile(fn, vars=g)
 
-
-# Path to the base directory of the project. On Windows the binary may
-# live in project/PCbuild/win32 or project/PCbuild/amd64.
-# set for cross builds
-if "_PYTHON_PROJECT_BASE" in os.environ:
-    project_base = os.path.abspath(os.environ["_PYTHON_PROJECT_BASE"])
-else:
-    if sys.executable:
-        project_base = os.path.dirname(os.path.abspath(sys.executable))
-    else:
-        # sys.executable can be empty if argv[0] has been changed and Python is
-        # unable to retrieve the real program name
-        project_base = os.getcwd()
-
-
-if os.name == 'nt':
-    def _fix_pcbuild(d):
-        if d and os.path.normcase(d).startswith(
-                os.path.normcase(os.path.join(PREFIX, "PCbuild"))):
-            return PREFIX
-        return d
-    project_base = _fix_pcbuild(project_base)
-    _sys_home = _fix_pcbuild(_sys_home)
-
-def _python_build():
-    if _sys_home:
-        return _is_python_source_dir(_sys_home)
-    return _is_python_source_dir(project_base)
-
-python_build = _python_build()
-
-
-# Calculate the build qualifier flags if they are defined.  Adding the flags
-# to the include and lib directories only makes sense for an installation, not
-# an in-source build.
-build_flags = ''
-try:
-    if not python_build:
-        build_flags = sys.abiflags
-except AttributeError:
-    # It's not a configure-based build, so the sys module doesn't have
-    # this attribute, which is fine.
-    pass
-
-
-def get_python_inc(plat_specific=0, prefix=None):
-    """Return the directory containing installed Python header files.
-
-    If 'plat_specific' is false (the default), this is the path to the
-    non-platform-specific header files, i.e. Python.h and so on;
-    otherwise, this is the path to platform-specific header files
-    (namely pyconfig.h).
-
-    If 'prefix' is supplied, use it instead of sys.base_prefix or
-    sys.base_exec_prefix -- i.e., ignore 'plat_specific'.
-    """
-    if prefix is None:
-        prefix = plat_specific and BASE_EXEC_PREFIX or BASE_PREFIX
-    if os.name == "posix":
-        if python_build:
-            # Assume the executable is in the build directory.  The
-            # pyconfig.h file should be in the same directory.  Since
-            # the build directory may not be the source directory, we
-            # must use "srcdir" from the makefile to find the "Include"
-            # directory.
-            if plat_specific:
-                return _sys_home or project_base
-            else:
-                incdir = os.path.join(get_config_var('srcdir'), 'Include')
-                return os.path.normpath(incdir)
-        python_dir = 'python' + get_python_version() + build_flags
-        return os.path.join(prefix, "include", python_dir)
-    elif os.name == "nt":
-        if python_build:
-            # Include both the include and PC dir to ensure we can find
-            # pyconfig.h
-            return (os.path.join(prefix, "include") + os.path.pathsep +
-                    os.path.join(prefix, "PC"))
-        return os.path.join(prefix, "include")
-    else:
-        raise DistutilsPlatformError(
-            "I don't know where Python installs its C header files "
-            "on platform '%s'" % os.name)
+_python_build = partial(is_python_build, check_home=True)
 
 
 def customize_compiler(compiler):
@@ -230,8 +158,6 @@ def get_makefile_filename():
     return os.path.join(lib_dir, config_file, 'Makefile')
 
 
-_config_vars = None
-
 def _init_posix():
     """Initialize the module as appropriate for POSIX systems."""
     # _sysconfigdata is generated at build time, see the sysconfig module
diff --git a/Lib/sysconfig.py b/Lib/sysconfig.py
index f42adb33d2a254..bdd5c6135662f6 100644
--- a/Lib/sysconfig.py
+++ b/Lib/sysconfig.py
@@ -713,6 +713,46 @@ def get_python_version():
     return _PY_VERSION_SHORT
 
 
+def get_python_inc(plat_specific=0, prefix=None):
+    """Return the directory containing installed Python header files.
+
+    If 'plat_specific' is false (the default), this is the path to the
+    non-platform-specific header files, i.e. Python.h and so on;
+    otherwise, this is the path to platform-specific header files
+    (namely pyconfig.h).
+
+    If 'prefix' is supplied, use it instead of sys.base_prefix or
+    sys.base_exec_prefix -- i.e., ignore 'plat_specific'.
+    """
+    if prefix is None:
+        prefix = plat_specific and _BASE_EXEC_PREFIX or _BASE_PREFIX
+    if os.name == "posix":
+        if _PYTHON_BUILD:
+            # Assume the executable is in the build directory.  The
+            # pyconfig.h file should be in the same directory.  Since
+            # the build directory may not be the source directory, we
+            # must use "srcdir" from the makefile to find the "Include"
+            # directory.
+            if plat_specific:
+                return _sys_home or _PROJECT_BASE
+            else:
+                incdir = os.path.join(get_config_var('srcdir'), 'Include')
+                return os.path.normpath(incdir)
+        python_dir = 'python' + get_python_version() + build_flags
+        return os.path.join(prefix, "include", python_dir)
+    elif os.name == "nt":
+        if _PYTHON_BUILD:
+            # Include both the include and PC dir to ensure we can find
+            # pyconfig.h
+            return (os.path.join(prefix, "include") + os.path.pathsep +
+                    os.path.join(prefix, "PC"))
+        return os.path.join(prefix, "include")
+    else:
+        raise DistutilsPlatformError(
+            "I don't know where Python installs its C header files "
+            "on platform '%s'" % os.name)
+
+
 def get_python_lib(plat_specific=0, standard_lib=0, prefix=None):
     """Return the directory containing the Python library (standard or
     site additions).

From 09f2617f843843b834faa8df07c2f919230666dc Mon Sep 17 00:00:00 2001
From: Lumir Balhar <lbalhar@redhat.com>
Date: Thu, 15 Oct 2020 12:33:17 +0200
Subject: [PATCH 05/24] Move the rest of functions to sysconfig

---
 Lib/distutils/sysconfig.py | 216 ++-----------------------------------
 Lib/sysconfig.py           |  73 +++++++++++++
 2 files changed, 81 insertions(+), 208 deletions(-)

diff --git a/Lib/distutils/sysconfig.py b/Lib/distutils/sysconfig.py
index dc442d4e58b96f..273989bd32dfc2 100644
--- a/Lib/distutils/sysconfig.py
+++ b/Lib/distutils/sysconfig.py
@@ -26,16 +26,22 @@
 from sysconfig import _PROJECT_BASE as project_base
 from sysconfig import _PYTHON_BUILD as python_build
 from sysconfig import _CONFIG_VARS as _config_vars
+from sysconfig import _init_posix as sysconfig_init_posix
 from sysconfig import parse_config_h as sysconfig_parse_config_h
 from sysconfig import _parse_makefile as sysconfig_parse_makefile
 
+from sysconfig import _init_non_posix
 from sysconfig import _is_python_source_dir
 from sysconfig import _sys_home
 
 from sysconfig import build_flags
+from sysconfig import customize_compiler
 from sysconfig import expand_makefile_vars
 from sysconfig import is_python_build
+from sysconfig import get_config_h_filename
 from sysconfig import get_config_var
+from sysconfig import get_config_vars
+from sysconfig import get_makefile_filename
 from sysconfig import get_python_inc
 from sysconfig import get_python_version
 from sysconfig import get_python_lib
@@ -59,211 +65,5 @@ def parse_makefile(fn, g=None):
     return sysconfig_parse_makefile(fn, vars=g)
 
 _python_build = partial(is_python_build, check_home=True)
-
-
-def customize_compiler(compiler):
-    """Do any platform-specific customization of a CCompiler instance.
-
-    Mainly needed on Unix, so we can plug in the information that
-    varies across Unices and is stored in Python's Makefile.
-    """
-    if compiler.compiler_type == "unix":
-        if sys.platform == "darwin":
-            # Perform first-time customization of compiler-related
-            # config vars on OS X now that we know we need a compiler.
-            # This is primarily to support Pythons from binary
-            # installers.  The kind and paths to build tools on
-            # the user system may vary significantly from the system
-            # that Python itself was built on.  Also the user OS
-            # version and build tools may not support the same set
-            # of CPU architectures for universal builds.
-            global _config_vars
-            # Use get_config_var() to ensure _config_vars is initialized.
-            if not get_config_var('CUSTOMIZED_OSX_COMPILER'):
-                import _osx_support
-                _osx_support.customize_compiler(_config_vars)
-                _config_vars['CUSTOMIZED_OSX_COMPILER'] = 'True'
-
-        (cc, cxx, cflags, ccshared, ldshared, shlib_suffix, ar, ar_flags) = \
-            get_config_vars('CC', 'CXX', 'CFLAGS',
-                            'CCSHARED', 'LDSHARED', 'SHLIB_SUFFIX', 'AR', 'ARFLAGS')
-
-        if 'CC' in os.environ:
-            newcc = os.environ['CC']
-            if (sys.platform == 'darwin'
-                    and 'LDSHARED' not in os.environ
-                    and ldshared.startswith(cc)):
-                # On OS X, if CC is overridden, use that as the default
-                #       command for LDSHARED as well
-                ldshared = newcc + ldshared[len(cc):]
-            cc = newcc
-        if 'CXX' in os.environ:
-            cxx = os.environ['CXX']
-        if 'LDSHARED' in os.environ:
-            ldshared = os.environ['LDSHARED']
-        if 'CPP' in os.environ:
-            cpp = os.environ['CPP']
-        else:
-            cpp = cc + " -E"           # not always
-        if 'LDFLAGS' in os.environ:
-            ldshared = ldshared + ' ' + os.environ['LDFLAGS']
-        if 'CFLAGS' in os.environ:
-            cflags = cflags + ' ' + os.environ['CFLAGS']
-            ldshared = ldshared + ' ' + os.environ['CFLAGS']
-        if 'CPPFLAGS' in os.environ:
-            cpp = cpp + ' ' + os.environ['CPPFLAGS']
-            cflags = cflags + ' ' + os.environ['CPPFLAGS']
-            ldshared = ldshared + ' ' + os.environ['CPPFLAGS']
-        if 'AR' in os.environ:
-            ar = os.environ['AR']
-        if 'ARFLAGS' in os.environ:
-            archiver = ar + ' ' + os.environ['ARFLAGS']
-        else:
-            archiver = ar + ' ' + ar_flags
-
-        cc_cmd = cc + ' ' + cflags
-        compiler.set_executables(
-            preprocessor=cpp,
-            compiler=cc_cmd,
-            compiler_so=cc_cmd + ' ' + ccshared,
-            compiler_cxx=cxx,
-            linker_so=ldshared,
-            linker_exe=cc,
-            archiver=archiver)
-
-        compiler.shared_lib_extension = shlib_suffix
-
-
-def get_config_h_filename():
-    """Return full pathname of installed pyconfig.h file."""
-    if python_build:
-        if os.name == "nt":
-            inc_dir = os.path.join(_sys_home or project_base, "PC")
-        else:
-            inc_dir = _sys_home or project_base
-    else:
-        inc_dir = get_python_inc(plat_specific=1)
-
-    return os.path.join(inc_dir, 'pyconfig.h')
-
-
-def get_makefile_filename():
-    """Return full pathname of installed Makefile from the Python build."""
-    if python_build:
-        return os.path.join(_sys_home or project_base, "Makefile")
-    lib_dir = get_python_lib(plat_specific=0, standard_lib=1)
-    config_file = 'config-{}{}'.format(get_python_version(), build_flags)
-    if hasattr(sys.implementation, '_multiarch'):
-        config_file += '-%s' % sys.implementation._multiarch
-    return os.path.join(lib_dir, config_file, 'Makefile')
-
-
-def _init_posix():
-    """Initialize the module as appropriate for POSIX systems."""
-    # _sysconfigdata is generated at build time, see the sysconfig module
-    name = os.environ.get('_PYTHON_SYSCONFIGDATA_NAME',
-        '_sysconfigdata_{abi}_{platform}_{multiarch}'.format(
-        abi=sys.abiflags,
-        platform=sys.platform,
-        multiarch=getattr(sys.implementation, '_multiarch', ''),
-    ))
-    _temp = __import__(name, globals(), locals(), ['build_time_vars'], 0)
-    build_time_vars = _temp.build_time_vars
-    global _config_vars
-    _config_vars = {}
-    _config_vars.update(build_time_vars)
-
-
-def _init_nt():
-    """Initialize the module as appropriate for NT"""
-    g = {}
-    # set basic install directories
-    g['LIBDEST'] = get_python_lib(plat_specific=0, standard_lib=1)
-    g['BINLIBDEST'] = get_python_lib(plat_specific=1, standard_lib=1)
-
-    # XXX hmmm.. a normal install puts include files here
-    g['INCLUDEPY'] = get_python_inc(plat_specific=0)
-
-    g['EXT_SUFFIX'] = _imp.extension_suffixes()[0]
-    g['EXE'] = ".exe"
-    g['VERSION'] = get_python_version().replace(".", "")
-    g['BINDIR'] = os.path.dirname(os.path.abspath(sys.executable))
-
-    global _config_vars
-    _config_vars = g
-
-
-def get_config_vars(*args):
-    """With no arguments, return a dictionary of all configuration
-    variables relevant for the current platform.  Generally this includes
-    everything needed to build extensions and install both pure modules and
-    extensions.  On Unix, this means every variable defined in Python's
-    installed Makefile; on Windows it's a much smaller set.
-
-    With arguments, return a list of values that result from looking up
-    each argument in the configuration variable dictionary.
-    """
-    global _config_vars
-    if _config_vars is None:
-        func = globals().get("_init_" + os.name)
-        if func:
-            func()
-        else:
-            _config_vars = {}
-
-        # Normalized versions of prefix and exec_prefix are handy to have;
-        # in fact, these are the standard versions used most places in the
-        # Distutils.
-        _config_vars['prefix'] = PREFIX
-        _config_vars['exec_prefix'] = EXEC_PREFIX
-
-        # For backward compatibility, see issue19555
-        SO = _config_vars.get('EXT_SUFFIX')
-        if SO is not None:
-            _config_vars['SO'] = SO
-
-        # Always convert srcdir to an absolute path
-        srcdir = _config_vars.get('srcdir', project_base)
-        if os.name == 'posix':
-            if python_build:
-                # If srcdir is a relative path (typically '.' or '..')
-                # then it should be interpreted relative to the directory
-                # containing Makefile.
-                base = os.path.dirname(get_makefile_filename())
-                srcdir = os.path.join(base, srcdir)
-            else:
-                # srcdir is not meaningful since the installation is
-                # spread about the filesystem.  We choose the
-                # directory containing the Makefile since we know it
-                # exists.
-                srcdir = os.path.dirname(get_makefile_filename())
-        _config_vars['srcdir'] = os.path.abspath(os.path.normpath(srcdir))
-
-        # Convert srcdir into an absolute path if it appears necessary.
-        # Normally it is relative to the build directory.  However, during
-        # testing, for example, we might be running a non-installed python
-        # from a different directory.
-        if python_build and os.name == "posix":
-            base = project_base
-            if (not os.path.isabs(_config_vars['srcdir']) and
-                base != os.getcwd()):
-                # srcdir is relative and we are not in the same directory
-                # as the executable. Assume executable is in the build
-                # directory and make srcdir absolute.
-                srcdir = os.path.join(base, _config_vars['srcdir'])
-                _config_vars['srcdir'] = os.path.normpath(srcdir)
-
-        # OS X platforms require special customization to handle
-        # multi-architecture, multi-os-version installers
-        if sys.platform == 'darwin':
-            import _osx_support
-            _osx_support.customize_config_vars(_config_vars)
-
-    if args:
-        vals = []
-        for name in args:
-            vals.append(_config_vars.get(name))
-        return vals
-    else:
-        return _config_vars
-
+_init_posix = partial(sysconfig_init_posix, _config_vars)
+_init_nt = partial(_init_non_posix, _config_vars)
diff --git a/Lib/sysconfig.py b/Lib/sysconfig.py
index bdd5c6135662f6..83e3212487b7c7 100644
--- a/Lib/sysconfig.py
+++ b/Lib/sysconfig.py
@@ -823,6 +823,79 @@ def expand_makefile_vars(s, vars):
     return s
 
 
+def customize_compiler(compiler):
+    """Do any platform-specific customization of a CCompiler instance.
+
+    Mainly needed on Unix, so we can plug in the information that
+    varies across Unices and is stored in Python's Makefile.
+    """
+    if compiler.compiler_type == "unix":
+        if sys.platform == "darwin":
+            # Perform first-time customization of compiler-related
+            # config vars on OS X now that we know we need a compiler.
+            # This is primarily to support Pythons from binary
+            # installers.  The kind and paths to build tools on
+            # the user system may vary significantly from the system
+            # that Python itself was built on.  Also the user OS
+            # version and build tools may not support the same set
+            # of CPU architectures for universal builds.
+            global _CONFIG_VARS
+            # Use get_config_var() to ensure _CONFIG_VARS is initialized.
+            if not get_config_var('CUSTOMIZED_OSX_COMPILER'):
+                import _osx_support
+                _osx_support.customize_compiler(_CONFIG_VARS)
+                _CONFIG_VARS['CUSTOMIZED_OSX_COMPILER'] = 'True'
+
+        (cc, cxx, cflags, ccshared, ldshared, shlib_suffix, ar, ar_flags) = \
+            get_config_vars('CC', 'CXX', 'CFLAGS',
+                            'CCSHARED', 'LDSHARED', 'SHLIB_SUFFIX', 'AR', 'ARFLAGS')
+
+        if 'CC' in os.environ:
+            newcc = os.environ['CC']
+            if (sys.platform == 'darwin'
+                    and 'LDSHARED' not in os.environ
+                    and ldshared.startswith(cc)):
+                # On OS X, if CC is overridden, use that as the default
+                #       command for LDSHARED as well
+                ldshared = newcc + ldshared[len(cc):]
+            cc = newcc
+        if 'CXX' in os.environ:
+            cxx = os.environ['CXX']
+        if 'LDSHARED' in os.environ:
+            ldshared = os.environ['LDSHARED']
+        if 'CPP' in os.environ:
+            cpp = os.environ['CPP']
+        else:
+            cpp = cc + " -E"           # not always
+        if 'LDFLAGS' in os.environ:
+            ldshared = ldshared + ' ' + os.environ['LDFLAGS']
+        if 'CFLAGS' in os.environ:
+            cflags = cflags + ' ' + os.environ['CFLAGS']
+            ldshared = ldshared + ' ' + os.environ['CFLAGS']
+        if 'CPPFLAGS' in os.environ:
+            cpp = cpp + ' ' + os.environ['CPPFLAGS']
+            cflags = cflags + ' ' + os.environ['CPPFLAGS']
+            ldshared = ldshared + ' ' + os.environ['CPPFLAGS']
+        if 'AR' in os.environ:
+            ar = os.environ['AR']
+        if 'ARFLAGS' in os.environ:
+            archiver = ar + ' ' + os.environ['ARFLAGS']
+        else:
+            archiver = ar + ' ' + ar_flags
+
+        cc_cmd = cc + ' ' + cflags
+        compiler.set_executables(
+            preprocessor=cpp,
+            compiler=cc_cmd,
+            compiler_so=cc_cmd + ' ' + ccshared,
+            compiler_cxx=cxx,
+            linker_so=ldshared,
+            linker_exe=cc,
+            archiver=archiver)
+
+        compiler.shared_lib_extension = shlib_suffix
+
+
 def _print_dict(title, data):
     for index, (key, value) in enumerate(sorted(data.items())):
         if index == 0:

From 24e0584bf56ca11637e0e77f85dec9d33099956a Mon Sep 17 00:00:00 2001
From: Lumir Balhar <lbalhar@redhat.com>
Date: Fri, 16 Oct 2020 07:39:11 +0200
Subject: [PATCH 06/24] Import regexes used in tests

---
 Lib/distutils/sysconfig.py | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/Lib/distutils/sysconfig.py b/Lib/distutils/sysconfig.py
index 273989bd32dfc2..3ddce70d6d3a72 100644
--- a/Lib/distutils/sysconfig.py
+++ b/Lib/distutils/sysconfig.py
@@ -34,6 +34,10 @@
 from sysconfig import _is_python_source_dir
 from sysconfig import _sys_home
 
+from sysconfig import _variable_rx
+from sysconfig import _findvar1_rx
+from sysconfig import _findvar2_rx
+
 from sysconfig import build_flags
 from sysconfig import customize_compiler
 from sysconfig import expand_makefile_vars

From b9ee651258c00d17543521a13796a123a0d53e08 Mon Sep 17 00:00:00 2001
From: Lumir Balhar <lbalhar@redhat.com>
Date: Fri, 16 Oct 2020 07:47:34 +0200
Subject: [PATCH 07/24] Implement compatibility option for parse_makefile

---
 Lib/distutils/sysconfig.py | 2 +-
 Lib/sysconfig.py           | 7 +++++--
 2 files changed, 6 insertions(+), 3 deletions(-)

diff --git a/Lib/distutils/sysconfig.py b/Lib/distutils/sysconfig.py
index 3ddce70d6d3a72..22fc067a38314a 100644
--- a/Lib/distutils/sysconfig.py
+++ b/Lib/distutils/sysconfig.py
@@ -66,7 +66,7 @@ def parse_config_h(fp, g=None):
 
 
 def parse_makefile(fn, g=None):
-    return sysconfig_parse_makefile(fn, vars=g)
+    return sysconfig_parse_makefile(fn, vars=g, distutils_compat=True)
 
 _python_build = partial(is_python_build, check_home=True)
 _init_posix = partial(sysconfig_init_posix, _config_vars)
diff --git a/Lib/sysconfig.py b/Lib/sysconfig.py
index 83e3212487b7c7..afddfb31460a69 100644
--- a/Lib/sysconfig.py
+++ b/Lib/sysconfig.py
@@ -223,7 +223,7 @@ def _get_default_scheme():
 
 
 
-def _parse_makefile(filename, vars=None):
+def _parse_makefile(filename, vars=None, distutils_compat=False):
     """Parse a Makefile-style file.
 
     A dictionary containing name/value pairs is returned.  If an
@@ -331,9 +331,12 @@ def _parse_makefile(filename, vars=None):
                                 done[name] = value
 
             else:
+                # The same function in distutils would not add
+                # unresolved variable to the done dictionary
+                if not distutils_compat:
+                    done[name] = value
                 # bogus variable reference (e.g. "prefix=$/opt/python");
                 # just drop it since we can't deal
-                done[name] = value
                 variables.remove(name)
 
     # strip spurious spaces

From 12f92cf4861749f4b83231f60926af1983d89a50 Mon Sep 17 00:00:00 2001
From: Lumir Balhar <lbalhar@redhat.com>
Date: Mon, 19 Oct 2020 12:42:08 +0200
Subject: [PATCH 08/24] Do not use assignment in teardown to not lose reference
 to global dict

---
 Lib/distutils/tests/test_util.py | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/Lib/distutils/tests/test_util.py b/Lib/distutils/tests/test_util.py
index bf0d4333f9aeaa..d4a01c6e91ce2b 100644
--- a/Lib/distutils/tests/test_util.py
+++ b/Lib/distutils/tests/test_util.py
@@ -54,7 +54,8 @@ def tearDown(self):
             os.uname = self.uname
         else:
             del os.uname
-        sysconfig._config_vars = copy(self._config_vars)
+        sysconfig._config_vars.clear()
+        sysconfig._config_vars.update(self._config_vars)
         super(UtilTestCase, self).tearDown()
 
     def _set_uname(self, uname):

From 7b9b0c118999b0be248d5ab98e0f4b5c5751e659 Mon Sep 17 00:00:00 2001
From: Lumir Balhar <lbalhar@redhat.com>
Date: Tue, 20 Oct 2020 09:33:23 +0200
Subject: [PATCH 09/24] Ignore DeprecationWarning in pip code in ensurepip
 module

---
 Lib/ensurepip/__init__.py | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/Lib/ensurepip/__init__.py b/Lib/ensurepip/__init__.py
index 74530706be5c70..0f1df6e8a839d1 100644
--- a/Lib/ensurepip/__init__.py
+++ b/Lib/ensurepip/__init__.py
@@ -90,7 +90,8 @@ def _run_pip(args, additional_paths=None):
 sys.argv[1:] = {args}
 runpy.run_module("pip", run_name="__main__", alter_sys=True)
 """
-    return subprocess.run([sys.executable, "-c", code], check=True).returncode
+    return subprocess.run([sys.executable, '-W', 'ignore::DeprecationWarning',
+                           "-c", code], check=True).returncode
 
 
 def version():

From 6f5aa4f84229d032afab7488d000f1e07e46b230 Mon Sep 17 00:00:00 2001
From: Lumir Balhar <lbalhar@redhat.com>
Date: Tue, 20 Oct 2020 12:02:22 +0200
Subject: [PATCH 10/24] Improve setUp/tearDown of UnixCCompilerTestCase

---
 Lib/distutils/tests/test_unixccompiler.py | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/Lib/distutils/tests/test_unixccompiler.py b/Lib/distutils/tests/test_unixccompiler.py
index eefe4ba40291eb..24725ead1194ce 100644
--- a/Lib/distutils/tests/test_unixccompiler.py
+++ b/Lib/distutils/tests/test_unixccompiler.py
@@ -12,6 +12,7 @@ class UnixCCompilerTestCase(unittest.TestCase):
     def setUp(self):
         self._backup_platform = sys.platform
         self._backup_get_config_var = sysconfig.get_config_var
+        self._backup_config_vars = dict(sysconfig._config_vars)
         class CompilerWrapper(UnixCCompiler):
             def rpath_foo(self):
                 return self.runtime_library_dir_option('/foo')
@@ -20,6 +21,8 @@ def rpath_foo(self):
     def tearDown(self):
         sys.platform = self._backup_platform
         sysconfig.get_config_var = self._backup_get_config_var
+        sysconfig._config_vars.clear()
+        sysconfig._config_vars.update(self._backup_config_vars)
 
     @unittest.skipIf(sys.platform == 'win32', "can't test on Windows")
     def test_runtime_libdir_option(self):

From fca8adc5b0bfb7f1f24f1fd9ca7805c4f35bd6b3 Mon Sep 17 00:00:00 2001
From: Lumir Balhar <lbalhar@redhat.com>
Date: Wed, 21 Oct 2020 14:10:30 +0200
Subject: [PATCH 11/24] Improve or create setUp/tearDown methods for tests
 where sysconfig._CONFIG_VARS might be modified

---
 Lib/distutils/tests/test_build_clib.py       | 10 ++++++++++
 Lib/distutils/tests/test_build_ext.py        |  3 +++
 Lib/distutils/tests/test_config_cmd.py       |  4 ++++
 Lib/distutils/tests/test_install.py          |  9 +++++++++
 Lib/test/test_peg_generator/test_c_parser.py |  3 +++
 5 files changed, 29 insertions(+)

diff --git a/Lib/distutils/tests/test_build_clib.py b/Lib/distutils/tests/test_build_clib.py
index abd8313770ef7a..19e012a58ce8cb 100644
--- a/Lib/distutils/tests/test_build_clib.py
+++ b/Lib/distutils/tests/test_build_clib.py
@@ -2,6 +2,7 @@
 import unittest
 import os
 import sys
+import sysconfig
 
 from test.support import run_unittest, missing_compiler_executable
 
@@ -13,6 +14,15 @@ class BuildCLibTestCase(support.TempdirManager,
                         support.LoggingSilencer,
                         unittest.TestCase):
 
+    def setUp(self):
+        super().setUp()
+        self._backup_CONFIG_VARS = dict(sysconfig._CONFIG_VARS)
+
+    def tearDown(self):
+        super().tearDown()
+        sysconfig._CONFIG_VARS.clear()
+        sysconfig._CONFIG_VARS.update(self._backup_CONFIG_VARS)
+
     def test_check_library_dist(self):
         pkg_dir, dist = self.create_dist()
         cmd = build_clib(dist)
diff --git a/Lib/distutils/tests/test_build_ext.py b/Lib/distutils/tests/test_build_ext.py
index 90f7bb066917bc..8e7364d2a2cb5f 100644
--- a/Lib/distutils/tests/test_build_ext.py
+++ b/Lib/distutils/tests/test_build_ext.py
@@ -35,6 +35,7 @@ def setUp(self):
         site.USER_BASE = self.mkdtemp()
         from distutils.command import build_ext
         build_ext.USER_BASE = site.USER_BASE
+        self.old_config_vars = dict(sysconfig._config_vars)
 
         # bpo-30132: On Windows, a .pdb file may be created in the current
         # working directory. Create a temporary working directory to cleanup
@@ -48,6 +49,8 @@ def tearDown(self):
         site.USER_BASE = self.old_user_base
         from distutils.command import build_ext
         build_ext.USER_BASE = self.old_user_base
+        sysconfig._config_vars.clear()
+        sysconfig._config_vars.update(self.old_config_vars)
         super(BuildExtTestCase, self).tearDown()
 
     def build_ext(self, *args, **kwargs):
diff --git a/Lib/distutils/tests/test_config_cmd.py b/Lib/distutils/tests/test_config_cmd.py
index 9aeab07b468361..0127ba71fc4bc4 100644
--- a/Lib/distutils/tests/test_config_cmd.py
+++ b/Lib/distutils/tests/test_config_cmd.py
@@ -2,6 +2,7 @@
 import unittest
 import os
 import sys
+import sysconfig
 from test.support import run_unittest, missing_compiler_executable
 
 from distutils.command.config import dump_file, config
@@ -21,9 +22,12 @@ def setUp(self):
         self._logs = []
         self.old_log = log.info
         log.info = self._info
+        self.old_config_vars = dict(sysconfig._CONFIG_VARS)
 
     def tearDown(self):
         log.info = self.old_log
+        sysconfig._CONFIG_VARS.clear()
+        sysconfig._CONFIG_VARS.update(self.old_config_vars)
         super(ConfigTestCase, self).tearDown()
 
     def test_dump_file(self):
diff --git a/Lib/distutils/tests/test_install.py b/Lib/distutils/tests/test_install.py
index 21a7b7c85c49da..0632024b3585ce 100644
--- a/Lib/distutils/tests/test_install.py
+++ b/Lib/distutils/tests/test_install.py
@@ -29,6 +29,15 @@ class InstallTestCase(support.TempdirManager,
                       support.LoggingSilencer,
                       unittest.TestCase):
 
+    def setUp(self):
+        super().setUp()
+        self._backup_config_vars = dict(sysconfig._config_vars)
+
+    def tearDown(self):
+        super().tearDown()
+        sysconfig._config_vars.clear()
+        sysconfig._config_vars.update(self._backup_config_vars)
+
     def test_home_installation_scheme(self):
         # This ensure two things:
         # - that --home generates the desired set of directory names
diff --git a/Lib/test/test_peg_generator/test_c_parser.py b/Lib/test/test_peg_generator/test_c_parser.py
index b7e80f0d351a26..3852cfbc477b6b 100644
--- a/Lib/test/test_peg_generator/test_c_parser.py
+++ b/Lib/test/test_peg_generator/test_c_parser.py
@@ -70,6 +70,7 @@ def test_parse(self):
 
 class TestCParser(TempdirManager, unittest.TestCase):
     def setUp(self):
+        self._backup_config_vars = dict(sysconfig._CONFIG_VARS)
         cmd = support.missing_compiler_executable()
         if cmd is not None:
             self.skipTest("The %r command is not found" % cmd)
@@ -81,6 +82,8 @@ def setUp(self):
 
     def tearDown(self):
         super(TestCParser, self).tearDown()
+        sysconfig._CONFIG_VARS.clear()
+        sysconfig._CONFIG_VARS.update(self._backup_config_vars)
 
     def build_extension(self, grammar_source):
         grammar = parse_string(grammar_source, GrammarParser)

From 318428db0ffaa69f7210f30adb42f824ca576e39 Mon Sep 17 00:00:00 2001
From: Lumir Balhar <lbalhar@redhat.com>
Date: Fri, 23 Oct 2020 12:10:59 +0200
Subject: [PATCH 12/24] Rename `distutils_compat` to `keep_unresolved` and
 reverse the logic

---
 Lib/distutils/sysconfig.py | 2 +-
 Lib/sysconfig.py           | 8 ++++----
 2 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/Lib/distutils/sysconfig.py b/Lib/distutils/sysconfig.py
index 22fc067a38314a..b0b843f6703e1e 100644
--- a/Lib/distutils/sysconfig.py
+++ b/Lib/distutils/sysconfig.py
@@ -66,7 +66,7 @@ def parse_config_h(fp, g=None):
 
 
 def parse_makefile(fn, g=None):
-    return sysconfig_parse_makefile(fn, vars=g, distutils_compat=True)
+    return sysconfig_parse_makefile(fn, vars=g, keep_unresolved=False)
 
 _python_build = partial(is_python_build, check_home=True)
 _init_posix = partial(sysconfig_init_posix, _config_vars)
diff --git a/Lib/sysconfig.py b/Lib/sysconfig.py
index afddfb31460a69..82b5861634f12b 100644
--- a/Lib/sysconfig.py
+++ b/Lib/sysconfig.py
@@ -223,7 +223,7 @@ def _get_default_scheme():
 
 
 
-def _parse_makefile(filename, vars=None, distutils_compat=False):
+def _parse_makefile(filename, vars=None, keep_unresolved=True):
     """Parse a Makefile-style file.
 
     A dictionary containing name/value pairs is returned.  If an
@@ -331,9 +331,9 @@ def _parse_makefile(filename, vars=None, distutils_compat=False):
                                 done[name] = value
 
             else:
-                # The same function in distutils would not add
-                # unresolved variable to the done dictionary
-                if not distutils_compat:
+                # Adds unresolved variables to the done dict.
+                # This is disabled when called from distutils.sysconfig
+                if keep_unresolved:
                     done[name] = value
                 # bogus variable reference (e.g. "prefix=$/opt/python");
                 # just drop it since we can't deal

From 6136978d0870befce5a8d66f9c2f366751f1d66c Mon Sep 17 00:00:00 2001
From: Lumir Balhar <lbalhar@redhat.com>
Date: Fri, 23 Oct 2020 12:23:01 +0200
Subject: [PATCH 13/24] Merge all import from sysconfig to one statement

---
 Lib/distutils/sysconfig.py | 55 +++++++++++++++++++-------------------
 1 file changed, 28 insertions(+), 27 deletions(-)

diff --git a/Lib/distutils/sysconfig.py b/Lib/distutils/sysconfig.py
index b0b843f6703e1e..6f30f059fb9df7 100644
--- a/Lib/distutils/sysconfig.py
+++ b/Lib/distutils/sysconfig.py
@@ -19,36 +19,37 @@
 
 from .errors import DistutilsPlatformError
 
-from sysconfig import _PREFIX as PREFIX
-from sysconfig import _BASE_PREFIX as BASE_PREFIX
-from sysconfig import _EXEC_PREFIX as EXEC_PREFIX
-from sysconfig import _BASE_EXEC_PREFIX as BASE_EXEC_PREFIX
-from sysconfig import _PROJECT_BASE as project_base
-from sysconfig import _PYTHON_BUILD as python_build
-from sysconfig import _CONFIG_VARS as _config_vars
-from sysconfig import _init_posix as sysconfig_init_posix
-from sysconfig import parse_config_h as sysconfig_parse_config_h
-from sysconfig import _parse_makefile as sysconfig_parse_makefile
+from sysconfig import (
+    _PREFIX as PREFIX,
+    _BASE_PREFIX as BASE_PREFIX,
+    _EXEC_PREFIX as EXEC_PREFIX,
+    _BASE_EXEC_PREFIX as BASE_EXEC_PREFIX,
+    _PROJECT_BASE as project_base,
+    _PYTHON_BUILD as python_build,
+    _CONFIG_VARS as _config_vars,
+    _init_posix as sysconfig_init_posix,
+    parse_config_h as sysconfig_parse_config_h,
+    _parse_makefile as sysconfig_parse_makefile,
 
-from sysconfig import _init_non_posix
-from sysconfig import _is_python_source_dir
-from sysconfig import _sys_home
+    _init_non_posix,
+    _is_python_source_dir,
+    _sys_home,
 
-from sysconfig import _variable_rx
-from sysconfig import _findvar1_rx
-from sysconfig import _findvar2_rx
+    _variable_rx,
+    _findvar1_rx,
+    _findvar2_rx,
 
-from sysconfig import build_flags
-from sysconfig import customize_compiler
-from sysconfig import expand_makefile_vars
-from sysconfig import is_python_build
-from sysconfig import get_config_h_filename
-from sysconfig import get_config_var
-from sysconfig import get_config_vars
-from sysconfig import get_makefile_filename
-from sysconfig import get_python_inc
-from sysconfig import get_python_version
-from sysconfig import get_python_lib
+    customize_compiler,
+    expand_makefile_vars,
+    is_python_build,
+    get_config_h_filename,
+    get_config_var,
+    get_config_vars,
+    get_makefile_filename,
+    get_python_inc,
+    get_python_version,
+    get_python_lib,
+)
 
 if os.name == "nt":
     from sysconfig import _fix_pcbuild

From e635dbdd75d32cb71fd44f5563f9aff93c864262 Mon Sep 17 00:00:00 2001
From: Lumir Balhar <lbalhar@redhat.com>
Date: Fri, 23 Oct 2020 12:31:51 +0200
Subject: [PATCH 14/24] Allow import of sysconfig when re module is not
 available

---
 Lib/sysconfig.py | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/Lib/sysconfig.py b/Lib/sysconfig.py
index 82b5861634f12b..cefa8b07697bfa 100644
--- a/Lib/sysconfig.py
+++ b/Lib/sysconfig.py
@@ -1,7 +1,6 @@
 """Access to Python's configuration information."""
 
 import os
-import re
 import sys
 from os.path import pardir, realpath
 from distutils.errors import DistutilsPlatformError
@@ -134,9 +133,13 @@ def joinuser(*args):
 
 # Regexes needed for parsing Makefile (and similar syntaxes,
 # like old-style Setup files).
-_variable_rx = re.compile(r"([a-zA-Z][a-zA-Z0-9_]+)\s*=\s*(.*)")
-_findvar1_rx = re.compile(r"\$\(([A-Za-z][A-Za-z0-9_]*)\)")
-_findvar2_rx = re.compile(r"\${([A-Za-z][A-Za-z0-9_]*)}")
+try:
+    import re
+    _variable_rx = re.compile(r"([a-zA-Z][a-zA-Z0-9_]+)\s*=\s*(.*)")
+    _findvar1_rx = re.compile(r"\$\(([A-Za-z][A-Za-z0-9_]*)\)")
+    _findvar2_rx = re.compile(r"\${([A-Za-z][A-Za-z0-9_]*)}")
+except ImportError:
+    pass
 
 
 def _safe_realpath(path):

From d8a8cf02ef965014f013aee73e72bd308fb9ba8d Mon Sep 17 00:00:00 2001
From: Lumir Balhar <lbalhar@redhat.com>
Date: Fri, 23 Oct 2020 13:13:57 +0200
Subject: [PATCH 15/24] Add a TODO comment about PEP 632

---
 Lib/test/support/__init__.py | 1 +
 1 file changed, 1 insertion(+)

diff --git a/Lib/test/support/__init__.py b/Lib/test/support/__init__.py
index 5a45d78be91663..80f3a04fcc6180 100644
--- a/Lib/test/support/__init__.py
+++ b/Lib/test/support/__init__.py
@@ -1667,6 +1667,7 @@ def missing_compiler_executable(cmd_names=[]):
     missing.
 
     """
+    # TODO (PEP 632): alternate check without using distutils
     from distutils import ccompiler, sysconfig, spawn, errors
     compiler = ccompiler.new_compiler()
     sysconfig.customize_compiler(compiler)

From e317db5a09f01861d8deb33023aaf3dcf59dad41 Mon Sep 17 00:00:00 2001
From: Lumir Balhar <lbalhar@redhat.com>
Date: Fri, 23 Oct 2020 13:38:24 +0200
Subject: [PATCH 16/24] Mark distutils.sysconfig as deprecated in docs

---
 Doc/distutils/apiref.rst | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/Doc/distutils/apiref.rst b/Doc/distutils/apiref.rst
index 6c69c11ccaa9a8..3b1d73f962fc43 100644
--- a/Doc/distutils/apiref.rst
+++ b/Doc/distutils/apiref.rst
@@ -1452,6 +1452,8 @@ name.
 
 .. module:: distutils.sysconfig
    :synopsis: Low-level access to configuration information of the Python interpreter.
+.. deprecated:: 3.10
+   :mod:`distutils.sysconfig` has been merged to :mod:`sysconfig`.
 .. moduleauthor:: Fred L. Drake, Jr. <fdrake@acm.org>
 .. moduleauthor:: Greg Ward <gward@python.net>
 .. sectionauthor:: Fred L. Drake, Jr. <fdrake@acm.org>

From 17206f066c9aedbfc1e6cfe889936472f590891d Mon Sep 17 00:00:00 2001
From: Lumir Balhar <lbalhar@redhat.com>
Date: Fri, 23 Oct 2020 13:38:43 +0200
Subject: [PATCH 17/24] Copy docs for get_python_inc and get_python_lib from
 distutils.sysconfig to sysconfig

---
 Doc/library/sysconfig.rst | 24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)

diff --git a/Doc/library/sysconfig.rst b/Doc/library/sysconfig.rst
index c9306e9bf9de16..4f0a65dd4c9665 100644
--- a/Doc/library/sysconfig.rst
+++ b/Doc/library/sysconfig.rst
@@ -224,6 +224,30 @@ Other functions
 
    Return the path of :file:`Makefile`.
 
+The following functions have been moved here from :mod:`distutils.sysconfig`
+when this module has been deprecated.
+
+.. function:: get_python_inc([plat_specific[, prefix]])
+
+   Return the directory for either the general or platform-dependent C include
+   files.  If *plat_specific* is true, the platform-dependent include directory is
+   returned; if false or omitted, the platform-independent directory is returned.
+   If *prefix* is given, it is used as either the prefix instead of
+   :const:`PREFIX`, or as the exec-prefix instead of :const:`EXEC_PREFIX` if
+   *plat_specific* is true.
+
+
+.. function:: get_python_lib([plat_specific[, standard_lib[, prefix]]])
+
+   Return the directory for either the general or platform-dependent library
+   installation.  If *plat_specific* is true, the platform-dependent include
+   directory is returned; if false or omitted, the platform-independent directory
+   is returned.  If *prefix* is given, it is used as either the prefix instead of
+   :const:`PREFIX`, or as the exec-prefix instead of :const:`EXEC_PREFIX` if
+   *plat_specific* is true.  If *standard_lib* is true, the directory for the
+   standard library is returned rather than the directory for the installation of
+   third-party extensions.
+
 Using :mod:`sysconfig` as a script
 ----------------------------------
 

From 04ef7af729ccc31a111728920695962ab5431d4b Mon Sep 17 00:00:00 2001
From: Lumir Balhar <lbalhar@redhat.com>
Date: Sat, 24 Oct 2020 07:36:23 +0200
Subject: [PATCH 18/24] Move customize_compiler back to distutils.sysconfig as
 it'll be removedtogether with the module.

---
 Lib/distutils/sysconfig.py | 75 +++++++++++++++++++++++++++++++++++++-
 Lib/sysconfig.py           | 73 -------------------------------------
 2 files changed, 74 insertions(+), 74 deletions(-)

diff --git a/Lib/distutils/sysconfig.py b/Lib/distutils/sysconfig.py
index 6f30f059fb9df7..1ce2d0045505ac 100644
--- a/Lib/distutils/sysconfig.py
+++ b/Lib/distutils/sysconfig.py
@@ -39,7 +39,6 @@
     _findvar1_rx,
     _findvar2_rx,
 
-    customize_compiler,
     expand_makefile_vars,
     is_python_build,
     get_config_h_filename,
@@ -72,3 +71,77 @@ def parse_makefile(fn, g=None):
 _python_build = partial(is_python_build, check_home=True)
 _init_posix = partial(sysconfig_init_posix, _config_vars)
 _init_nt = partial(_init_non_posix, _config_vars)
+
+
+# customize_compiler is deprecated and won't be moved to another module
+def customize_compiler(compiler):
+    """Do any platform-specific customization of a CCompiler instance.
+
+    Mainly needed on Unix, so we can plug in the information that
+    varies across Unices and is stored in Python's Makefile.
+    """
+    if compiler.compiler_type == "unix":
+        if sys.platform == "darwin":
+            # Perform first-time customization of compiler-related
+            # config vars on OS X now that we know we need a compiler.
+            # This is primarily to support Pythons from binary
+            # installers.  The kind and paths to build tools on
+            # the user system may vary significantly from the system
+            # that Python itself was built on.  Also the user OS
+            # version and build tools may not support the same set
+            # of CPU architectures for universal builds.
+            global _config_vars
+            # Use get_config_var() to ensure _config_vars is initialized.
+            if not get_config_var('CUSTOMIZED_OSX_COMPILER'):
+                import _osx_support
+                _osx_support.customize_compiler(_config_vars)
+                _config_vars['CUSTOMIZED_OSX_COMPILER'] = 'True'
+
+        (cc, cxx, cflags, ccshared, ldshared, shlib_suffix, ar, ar_flags) = \
+            get_config_vars('CC', 'CXX', 'CFLAGS',
+                            'CCSHARED', 'LDSHARED', 'SHLIB_SUFFIX', 'AR', 'ARFLAGS')
+
+        if 'CC' in os.environ:
+            newcc = os.environ['CC']
+            if (sys.platform == 'darwin'
+                    and 'LDSHARED' not in os.environ
+                    and ldshared.startswith(cc)):
+                # On OS X, if CC is overridden, use that as the default
+                #       command for LDSHARED as well
+                ldshared = newcc + ldshared[len(cc):]
+            cc = newcc
+        if 'CXX' in os.environ:
+            cxx = os.environ['CXX']
+        if 'LDSHARED' in os.environ:
+            ldshared = os.environ['LDSHARED']
+        if 'CPP' in os.environ:
+            cpp = os.environ['CPP']
+        else:
+            cpp = cc + " -E"           # not always
+        if 'LDFLAGS' in os.environ:
+            ldshared = ldshared + ' ' + os.environ['LDFLAGS']
+        if 'CFLAGS' in os.environ:
+            cflags = cflags + ' ' + os.environ['CFLAGS']
+            ldshared = ldshared + ' ' + os.environ['CFLAGS']
+        if 'CPPFLAGS' in os.environ:
+            cpp = cpp + ' ' + os.environ['CPPFLAGS']
+            cflags = cflags + ' ' + os.environ['CPPFLAGS']
+            ldshared = ldshared + ' ' + os.environ['CPPFLAGS']
+        if 'AR' in os.environ:
+            ar = os.environ['AR']
+        if 'ARFLAGS' in os.environ:
+            archiver = ar + ' ' + os.environ['ARFLAGS']
+        else:
+            archiver = ar + ' ' + ar_flags
+
+        cc_cmd = cc + ' ' + cflags
+        compiler.set_executables(
+            preprocessor=cpp,
+            compiler=cc_cmd,
+            compiler_so=cc_cmd + ' ' + ccshared,
+            compiler_cxx=cxx,
+            linker_so=ldshared,
+            linker_exe=cc,
+            archiver=archiver)
+
+        compiler.shared_lib_extension = shlib_suffix
diff --git a/Lib/sysconfig.py b/Lib/sysconfig.py
index cefa8b07697bfa..4270b9ada2bac8 100644
--- a/Lib/sysconfig.py
+++ b/Lib/sysconfig.py
@@ -829,79 +829,6 @@ def expand_makefile_vars(s, vars):
     return s
 
 
-def customize_compiler(compiler):
-    """Do any platform-specific customization of a CCompiler instance.
-
-    Mainly needed on Unix, so we can plug in the information that
-    varies across Unices and is stored in Python's Makefile.
-    """
-    if compiler.compiler_type == "unix":
-        if sys.platform == "darwin":
-            # Perform first-time customization of compiler-related
-            # config vars on OS X now that we know we need a compiler.
-            # This is primarily to support Pythons from binary
-            # installers.  The kind and paths to build tools on
-            # the user system may vary significantly from the system
-            # that Python itself was built on.  Also the user OS
-            # version and build tools may not support the same set
-            # of CPU architectures for universal builds.
-            global _CONFIG_VARS
-            # Use get_config_var() to ensure _CONFIG_VARS is initialized.
-            if not get_config_var('CUSTOMIZED_OSX_COMPILER'):
-                import _osx_support
-                _osx_support.customize_compiler(_CONFIG_VARS)
-                _CONFIG_VARS['CUSTOMIZED_OSX_COMPILER'] = 'True'
-
-        (cc, cxx, cflags, ccshared, ldshared, shlib_suffix, ar, ar_flags) = \
-            get_config_vars('CC', 'CXX', 'CFLAGS',
-                            'CCSHARED', 'LDSHARED', 'SHLIB_SUFFIX', 'AR', 'ARFLAGS')
-
-        if 'CC' in os.environ:
-            newcc = os.environ['CC']
-            if (sys.platform == 'darwin'
-                    and 'LDSHARED' not in os.environ
-                    and ldshared.startswith(cc)):
-                # On OS X, if CC is overridden, use that as the default
-                #       command for LDSHARED as well
-                ldshared = newcc + ldshared[len(cc):]
-            cc = newcc
-        if 'CXX' in os.environ:
-            cxx = os.environ['CXX']
-        if 'LDSHARED' in os.environ:
-            ldshared = os.environ['LDSHARED']
-        if 'CPP' in os.environ:
-            cpp = os.environ['CPP']
-        else:
-            cpp = cc + " -E"           # not always
-        if 'LDFLAGS' in os.environ:
-            ldshared = ldshared + ' ' + os.environ['LDFLAGS']
-        if 'CFLAGS' in os.environ:
-            cflags = cflags + ' ' + os.environ['CFLAGS']
-            ldshared = ldshared + ' ' + os.environ['CFLAGS']
-        if 'CPPFLAGS' in os.environ:
-            cpp = cpp + ' ' + os.environ['CPPFLAGS']
-            cflags = cflags + ' ' + os.environ['CPPFLAGS']
-            ldshared = ldshared + ' ' + os.environ['CPPFLAGS']
-        if 'AR' in os.environ:
-            ar = os.environ['AR']
-        if 'ARFLAGS' in os.environ:
-            archiver = ar + ' ' + os.environ['ARFLAGS']
-        else:
-            archiver = ar + ' ' + ar_flags
-
-        cc_cmd = cc + ' ' + cflags
-        compiler.set_executables(
-            preprocessor=cpp,
-            compiler=cc_cmd,
-            compiler_so=cc_cmd + ' ' + ccshared,
-            compiler_cxx=cxx,
-            linker_so=ldshared,
-            linker_exe=cc,
-            archiver=archiver)
-
-        compiler.shared_lib_extension = shlib_suffix
-
-
 def _print_dict(title, data):
     for index, (key, value) in enumerate(sorted(data.items())):
         if index == 0:

From 60152550f32ca0fbbb09c2bde4f7522f6bc79d7b Mon Sep 17 00:00:00 2001
From: Lumir Balhar <lbalhar@redhat.com>
Date: Tue, 3 Nov 2020 14:24:33 +0100
Subject: [PATCH 19/24] Fix import of not-yet-initialized _CONFIG_VARS

---
 Lib/distutils/sysconfig.py | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/Lib/distutils/sysconfig.py b/Lib/distutils/sysconfig.py
index 1ce2d0045505ac..4a987b1732416b 100644
--- a/Lib/distutils/sysconfig.py
+++ b/Lib/distutils/sysconfig.py
@@ -26,7 +26,6 @@
     _BASE_EXEC_PREFIX as BASE_EXEC_PREFIX,
     _PROJECT_BASE as project_base,
     _PYTHON_BUILD as python_build,
-    _CONFIG_VARS as _config_vars,
     _init_posix as sysconfig_init_posix,
     parse_config_h as sysconfig_parse_config_h,
     _parse_makefile as sysconfig_parse_makefile,
@@ -50,6 +49,12 @@
     get_python_lib,
 )
 
+# This is better than
+# from sysconfig import _CONFIG_VARS as _config_vars
+# because it makes sure that the global dictionary is initialized
+# which might not be true in the time of import.
+_config_vars = get_config_vars()
+
 if os.name == "nt":
     from sysconfig import _fix_pcbuild
 
@@ -90,9 +95,7 @@ def customize_compiler(compiler):
             # that Python itself was built on.  Also the user OS
             # version and build tools may not support the same set
             # of CPU architectures for universal builds.
-            global _config_vars
-            # Use get_config_var() to ensure _config_vars is initialized.
-            if not get_config_var('CUSTOMIZED_OSX_COMPILER'):
+            if not _config_vars.get('CUSTOMIZED_OSX_COMPILER'):
                 import _osx_support
                 _osx_support.customize_compiler(_config_vars)
                 _config_vars['CUSTOMIZED_OSX_COMPILER'] = 'True'

From abc310bf67b268b09d207fc924f296b61ccc3240 Mon Sep 17 00:00:00 2001
From: Lumir Balhar <lbalhar@redhat.com>
Date: Thu, 5 Nov 2020 10:42:55 +0100
Subject: [PATCH 20/24] Switch global vars from regex objects to raw strings
 and import re only when needed

---
 Lib/distutils/extension.py |  3 ++-
 Lib/sysconfig.py           | 21 ++++++++++-----------
 2 files changed, 12 insertions(+), 12 deletions(-)

diff --git a/Lib/distutils/extension.py b/Lib/distutils/extension.py
index c507da360aa3d9..e85032ece8916f 100644
--- a/Lib/distutils/extension.py
+++ b/Lib/distutils/extension.py
@@ -4,6 +4,7 @@
 modules in setup scripts."""
 
 import os
+import re
 import warnings
 
 # This class is really only used by the "build_ext" command, so it might
@@ -161,7 +162,7 @@ def read_setup_file(filename):
             line = file.readline()
             if line is None:                # eof
                 break
-            if _variable_rx.match(line):    # VAR=VALUE, handled in first pass
+            if re.match(_variable_rx, line):    # VAR=VALUE, handled in first pass
                 continue
 
             if line[0] == line[-1] == "*":
diff --git a/Lib/sysconfig.py b/Lib/sysconfig.py
index 4270b9ada2bac8..449b225c80ebc2 100644
--- a/Lib/sysconfig.py
+++ b/Lib/sysconfig.py
@@ -133,13 +133,9 @@ def joinuser(*args):
 
 # Regexes needed for parsing Makefile (and similar syntaxes,
 # like old-style Setup files).
-try:
-    import re
-    _variable_rx = re.compile(r"([a-zA-Z][a-zA-Z0-9_]+)\s*=\s*(.*)")
-    _findvar1_rx = re.compile(r"\$\(([A-Za-z][A-Za-z0-9_]*)\)")
-    _findvar2_rx = re.compile(r"\${([A-Za-z][A-Za-z0-9_]*)}")
-except ImportError:
-    pass
+_variable_rx = r"([a-zA-Z][a-zA-Z0-9_]+)\s*=\s*(.*)"
+_findvar1_rx = r"\$\(([A-Za-z][A-Za-z0-9_]*)\)"
+_findvar2_rx = r"\${([A-Za-z][A-Za-z0-9_]*)}"
 
 
 def _safe_realpath(path):
@@ -233,6 +229,8 @@ def _parse_makefile(filename, vars=None, keep_unresolved=True):
     optional dictionary is passed in as the second argument, it is
     used instead of a new dictionary.
     """
+    import re
+
     if vars is None:
         vars = {}
     done = {}
@@ -245,7 +243,7 @@ def _parse_makefile(filename, vars=None, keep_unresolved=True):
     for line in lines:
         if line.startswith('#') or line.strip() == '':
             continue
-        m = _variable_rx.match(line)
+        m = re.match(_variable_rx, line)
         if m:
             n, v = m.group(1, 2)
             v = v.strip()
@@ -278,8 +276,8 @@ def _parse_makefile(filename, vars=None, keep_unresolved=True):
     while len(variables) > 0:
         for name in tuple(variables):
             value = notdone[name]
-            m1 = _findvar1_rx.search(value)
-            m2 = _findvar2_rx.search(value)
+            m1 = re.search(_findvar1_rx, value)
+            m2 = re.search(_findvar2_rx, value)
             if m1 and m2:
                 m = m1 if m1.start() < m2.start() else m2
             else:
@@ -812,6 +810,7 @@ def expand_makefile_vars(s, vars):
     variable expansions; if 'vars' is the output of 'parse_makefile()',
     you're fine.  Returns a variable-expanded version of 's'.
     """
+    import re
 
     # This algorithm does multiple expansion, so if vars['foo'] contains
     # "${bar}", it will expand ${foo} to ${bar}, and then expand
@@ -820,7 +819,7 @@ def expand_makefile_vars(s, vars):
     # according to make's variable expansion semantics.
 
     while True:
-        m = _findvar1_rx.search(s) or _findvar2_rx.search(s)
+        m = re.search(_findvar1_rx, s) or re.search(_findvar2_rx, s)
         if m:
             (beg, end) = m.span()
             s = s[0:beg] + vars.get(m.group(1)) + s[end:]

From 17aa9c44b62c3d20dae1df6a29a24fa97a79342a Mon Sep 17 00:00:00 2001
From: Lumir Balhar <lbalhar@redhat.com>
Date: Fri, 13 Nov 2020 09:21:14 +0100
Subject: [PATCH 21/24] Move get_python_lib and get_python_inc back to
 distutils.sysconfig

and deprecated them.
---
 Doc/distutils/apiref.rst   |  3 ++
 Doc/library/sysconfig.rst  | 23 ----------
 Lib/distutils/sysconfig.py | 91 ++++++++++++++++++++++++++++++++++++--
 Lib/sysconfig.py           | 86 -----------------------------------
 4 files changed, 91 insertions(+), 112 deletions(-)

diff --git a/Doc/distutils/apiref.rst b/Doc/distutils/apiref.rst
index 3b1d73f962fc43..743a05ca3553b3 100644
--- a/Doc/distutils/apiref.rst
+++ b/Doc/distutils/apiref.rst
@@ -1512,6 +1512,9 @@ for other parts of the :mod:`distutils` package.
    meaning for other platforms will vary.  The file is a platform-specific text
    file, if it exists. This function is only useful on POSIX platforms.
 
+The following functions are deprecated together with this module and they
+have no direct replacement.
+
 
 .. function:: get_python_inc([plat_specific[, prefix]])
 
diff --git a/Doc/library/sysconfig.rst b/Doc/library/sysconfig.rst
index 4f0a65dd4c9665..d4463f39fda24f 100644
--- a/Doc/library/sysconfig.rst
+++ b/Doc/library/sysconfig.rst
@@ -224,29 +224,6 @@ Other functions
 
    Return the path of :file:`Makefile`.
 
-The following functions have been moved here from :mod:`distutils.sysconfig`
-when this module has been deprecated.
-
-.. function:: get_python_inc([plat_specific[, prefix]])
-
-   Return the directory for either the general or platform-dependent C include
-   files.  If *plat_specific* is true, the platform-dependent include directory is
-   returned; if false or omitted, the platform-independent directory is returned.
-   If *prefix* is given, it is used as either the prefix instead of
-   :const:`PREFIX`, or as the exec-prefix instead of :const:`EXEC_PREFIX` if
-   *plat_specific* is true.
-
-
-.. function:: get_python_lib([plat_specific[, standard_lib[, prefix]]])
-
-   Return the directory for either the general or platform-dependent library
-   installation.  If *plat_specific* is true, the platform-dependent include
-   directory is returned; if false or omitted, the platform-independent directory
-   is returned.  If *prefix* is given, it is used as either the prefix instead of
-   :const:`PREFIX`, or as the exec-prefix instead of :const:`EXEC_PREFIX` if
-   *plat_specific* is true.  If *standard_lib* is true, the directory for the
-   standard library is returned rather than the directory for the installation of
-   third-party extensions.
 
 Using :mod:`sysconfig` as a script
 ----------------------------------
diff --git a/Lib/distutils/sysconfig.py b/Lib/distutils/sysconfig.py
index 4a987b1732416b..d274b8bf5f82d6 100644
--- a/Lib/distutils/sysconfig.py
+++ b/Lib/distutils/sysconfig.py
@@ -44,9 +44,7 @@
     get_config_var,
     get_config_vars,
     get_makefile_filename,
-    get_python_inc,
     get_python_version,
-    get_python_lib,
 )
 
 # This is better than
@@ -78,7 +76,9 @@ def parse_makefile(fn, g=None):
 _init_nt = partial(_init_non_posix, _config_vars)
 
 
-# customize_compiler is deprecated and won't be moved to another module
+# Following functions are deprecated together with this module and they
+# have no direct replacement
+
 def customize_compiler(compiler):
     """Do any platform-specific customization of a CCompiler instance.
 
@@ -148,3 +148,88 @@ def customize_compiler(compiler):
             archiver=archiver)
 
         compiler.shared_lib_extension = shlib_suffix
+
+
+def get_python_inc(plat_specific=0, prefix=None):
+    """Return the directory containing installed Python header files.
+
+    If 'plat_specific' is false (the default), this is the path to the
+    non-platform-specific header files, i.e. Python.h and so on;
+    otherwise, this is the path to platform-specific header files
+    (namely pyconfig.h).
+
+    If 'prefix' is supplied, use it instead of sys.base_prefix or
+    sys.base_exec_prefix -- i.e., ignore 'plat_specific'.
+    """
+    if prefix is None:
+        prefix = plat_specific and BASE_EXEC_PREFIX or BASE_PREFIX
+    if os.name == "posix":
+        if python_build:
+            # Assume the executable is in the build directory.  The
+            # pyconfig.h file should be in the same directory.  Since
+            # the build directory may not be the source directory, we
+            # must use "srcdir" from the makefile to find the "Include"
+            # directory.
+            if plat_specific:
+                return _sys_home or project_base
+            else:
+                incdir = os.path.join(get_config_var('srcdir'), 'Include')
+                return os.path.normpath(incdir)
+        python_dir = 'python' + get_python_version() + build_flags
+        return os.path.join(prefix, "include", python_dir)
+    elif os.name == "nt":
+        if python_build:
+            # Include both the include and PC dir to ensure we can find
+            # pyconfig.h
+            return (os.path.join(prefix, "include") + os.path.pathsep +
+                    os.path.join(prefix, "PC"))
+        return os.path.join(prefix, "include")
+    else:
+        raise DistutilsPlatformError(
+            "I don't know where Python installs its C header files "
+            "on platform '%s'" % os.name)
+
+
+def get_python_lib(plat_specific=0, standard_lib=0, prefix=None):
+    """Return the directory containing the Python library (standard or
+    site additions).
+
+    If 'plat_specific' is true, return the directory containing
+    platform-specific modules, i.e. any module from a non-pure-Python
+    module distribution; otherwise, return the platform-shared library
+    directory.  If 'standard_lib' is true, return the directory
+    containing standard Python library modules; otherwise, return the
+    directory for site-specific modules.
+
+    If 'prefix' is supplied, use it instead of sys.base_prefix or
+    sys.base_exec_prefix -- i.e., ignore 'plat_specific'.
+    """
+    if prefix is None:
+        if standard_lib:
+            prefix = plat_specific and BASE_EXEC_PREFIX or BASE_PREFIX
+        else:
+            prefix = plat_specific and EXEC_PREFIX or PREFIX
+
+    if os.name == "posix":
+        if plat_specific or standard_lib:
+            # Platform-specific modules (any module from a non-pure-Python
+            # module distribution) or standard Python library modules.
+            libdir = sys.platlibdir
+        else:
+            # Pure Python
+            libdir = "lib"
+        libpython = os.path.join(prefix, libdir,
+                                 "python" + get_python_version())
+        if standard_lib:
+            return libpython
+        else:
+            return os.path.join(libpython, "site-packages")
+    elif os.name == "nt":
+        if standard_lib:
+            return os.path.join(prefix, "Lib")
+        else:
+            return os.path.join(prefix, "Lib", "site-packages")
+    else:
+        raise DistutilsPlatformError(
+            "I don't know where Python installs its library "
+            "on platform '%s'" % os.name)
diff --git a/Lib/sysconfig.py b/Lib/sysconfig.py
index 449b225c80ebc2..0e0decd42716ed 100644
--- a/Lib/sysconfig.py
+++ b/Lib/sysconfig.py
@@ -3,7 +3,6 @@
 import os
 import sys
 from os.path import pardir, realpath
-from distutils.errors import DistutilsPlatformError
 
 __all__ = [
     'get_config_h_filename',
@@ -717,91 +716,6 @@ def get_python_version():
     return _PY_VERSION_SHORT
 
 
-def get_python_inc(plat_specific=0, prefix=None):
-    """Return the directory containing installed Python header files.
-
-    If 'plat_specific' is false (the default), this is the path to the
-    non-platform-specific header files, i.e. Python.h and so on;
-    otherwise, this is the path to platform-specific header files
-    (namely pyconfig.h).
-
-    If 'prefix' is supplied, use it instead of sys.base_prefix or
-    sys.base_exec_prefix -- i.e., ignore 'plat_specific'.
-    """
-    if prefix is None:
-        prefix = plat_specific and _BASE_EXEC_PREFIX or _BASE_PREFIX
-    if os.name == "posix":
-        if _PYTHON_BUILD:
-            # Assume the executable is in the build directory.  The
-            # pyconfig.h file should be in the same directory.  Since
-            # the build directory may not be the source directory, we
-            # must use "srcdir" from the makefile to find the "Include"
-            # directory.
-            if plat_specific:
-                return _sys_home or _PROJECT_BASE
-            else:
-                incdir = os.path.join(get_config_var('srcdir'), 'Include')
-                return os.path.normpath(incdir)
-        python_dir = 'python' + get_python_version() + build_flags
-        return os.path.join(prefix, "include", python_dir)
-    elif os.name == "nt":
-        if _PYTHON_BUILD:
-            # Include both the include and PC dir to ensure we can find
-            # pyconfig.h
-            return (os.path.join(prefix, "include") + os.path.pathsep +
-                    os.path.join(prefix, "PC"))
-        return os.path.join(prefix, "include")
-    else:
-        raise DistutilsPlatformError(
-            "I don't know where Python installs its C header files "
-            "on platform '%s'" % os.name)
-
-
-def get_python_lib(plat_specific=0, standard_lib=0, prefix=None):
-    """Return the directory containing the Python library (standard or
-    site additions).
-
-    If 'plat_specific' is true, return the directory containing
-    platform-specific modules, i.e. any module from a non-pure-Python
-    module distribution; otherwise, return the platform-shared library
-    directory.  If 'standard_lib' is true, return the directory
-    containing standard Python library modules; otherwise, return the
-    directory for site-specific modules.
-
-    If 'prefix' is supplied, use it instead of sys.base_prefix or
-    sys.base_exec_prefix -- i.e., ignore 'plat_specific'.
-    """
-    if prefix is None:
-        if standard_lib:
-            prefix = plat_specific and _BASE_EXEC_PREFIX or _BASE_PREFIX
-        else:
-            prefix = plat_specific and _EXEC_PREFIX or _PREFIX
-
-    if os.name == "posix":
-        if plat_specific or standard_lib:
-            # Platform-specific modules (any module from a non-pure-Python
-            # module distribution) or standard Python library modules.
-            libdir = sys.platlibdir
-        else:
-            # Pure Python
-            libdir = "lib"
-        libpython = os.path.join(prefix, libdir,
-                                 "python" + get_python_version())
-        if standard_lib:
-            return libpython
-        else:
-            return os.path.join(libpython, "site-packages")
-    elif os.name == "nt":
-        if standard_lib:
-            return os.path.join(prefix, "Lib")
-        else:
-            return os.path.join(prefix, "Lib", "site-packages")
-    else:
-        raise DistutilsPlatformError(
-            "I don't know where Python installs its library "
-            "on platform '%s'" % os.name)
-
-
 def expand_makefile_vars(s, vars):
     """Expand Makefile-style variables -- "${foo}" or "$(foo)" -- in
     'string' according to 'vars' (a dictionary mapping variable names to

From be181b67cef5393a85535245918a9267c8b0250b Mon Sep 17 00:00:00 2001
From: Lumir Balhar <lbalhar@redhat.com>
Date: Mon, 15 Feb 2021 12:53:59 +0100
Subject: [PATCH 22/24] News entry

---
 .../NEWS.d/next/Library/2021-02-15-12-52-23.bpo-41282.SenEje.rst | 1 +
 1 file changed, 1 insertion(+)
 create mode 100644 Misc/NEWS.d/next/Library/2021-02-15-12-52-23.bpo-41282.SenEje.rst

diff --git a/Misc/NEWS.d/next/Library/2021-02-15-12-52-23.bpo-41282.SenEje.rst b/Misc/NEWS.d/next/Library/2021-02-15-12-52-23.bpo-41282.SenEje.rst
new file mode 100644
index 00000000000000..95ac1831dbf2d3
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2021-02-15-12-52-23.bpo-41282.SenEje.rst
@@ -0,0 +1 @@
+:mod:`distutils.sysconfig` has been merged to :mod:`sysconfig`.

From e253a3d33a49f469468374492b7bb89c3300b4d0 Mon Sep 17 00:00:00 2001
From: Lumir Balhar <lbalhar@redhat.com>
Date: Fri, 16 Apr 2021 16:01:24 +0200
Subject: [PATCH 23/24] Restore build_flags accidentally removed during a
 rebase

---
 Lib/distutils/sysconfig.py | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/Lib/distutils/sysconfig.py b/Lib/distutils/sysconfig.py
index d274b8bf5f82d6..439040deb5619d 100644
--- a/Lib/distutils/sysconfig.py
+++ b/Lib/distutils/sysconfig.py
@@ -79,6 +79,19 @@ def parse_makefile(fn, g=None):
 # Following functions are deprecated together with this module and they
 # have no direct replacement
 
+# Calculate the build qualifier flags if they are defined.  Adding the flags
+# to the include and lib directories only makes sense for an installation, not
+# an in-source build.
+build_flags = ''
+try:
+    if not python_build:
+        build_flags = sys.abiflags
+except AttributeError:
+    # It's not a configure-based build, so the sys module doesn't have
+    # this attribute, which is fine.
+    pass
+
+
 def customize_compiler(compiler):
     """Do any platform-specific customization of a CCompiler instance.
 

From cd8e387f4530c1544a712a9ed9d464532a3975df Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Lum=C3=ADr=20=27Frenzy=27=20Balhar?=
 <frenzy.madness@gmail.com>
Date: Sun, 18 Apr 2021 11:26:06 +0200
Subject: [PATCH 24/24] Update Doc/distutils/apiref.rst
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Co-authored-by: Éric Araujo <merwok@netwok.org>
---
 Doc/distutils/apiref.rst | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Doc/distutils/apiref.rst b/Doc/distutils/apiref.rst
index 743a05ca3553b3..e4437f4106b519 100644
--- a/Doc/distutils/apiref.rst
+++ b/Doc/distutils/apiref.rst
@@ -1453,7 +1453,7 @@ name.
 .. module:: distutils.sysconfig
    :synopsis: Low-level access to configuration information of the Python interpreter.
 .. deprecated:: 3.10
-   :mod:`distutils.sysconfig` has been merged to :mod:`sysconfig`.
+   :mod:`distutils.sysconfig` has been merged into :mod:`sysconfig`.
 .. moduleauthor:: Fred L. Drake, Jr. <fdrake@acm.org>
 .. moduleauthor:: Greg Ward <gward@python.net>
 .. sectionauthor:: Fred L. Drake, Jr. <fdrake@acm.org>