bpo-45873: Get rid of bootstrap_python (#29717)

Instead we use $(PYTHON_FOR_REGEN) .../deepfreeze.py with the
frozen .h file as input, as we did for Windows in bpo-45850.

We also get rid of the code that generates the .h files
when make regen-frozen is run (i.e., .../make_frozen.py),
and the MANIFEST file.

Restore Python 3.8 and 3.9 as Windows host Python again

Co-authored-by: Kumar Aditya <[email protected]>

Author: gvanrossum

Makefile.pre.in

@@ -0,0 +1 @@
+Get rid of the ``_bootstrap_python`` build step. The deepfreeze.py script is now run using ``$(PYTHON_FOR_REGEN)`` which can be Python 3.7 or newer (on Windows, 3.8 or newer).

Misc/NEWS.d/next/Build/2021-11-23-04-28-40.bpo-45873.9dldZ4.rst

@@ -31,13 +31,13 @@
 @if "%_Py_EXTERNALS_DIR%"=="" (set _Py_EXTERNALS_DIR=%~dp0\..\externals)
 
 @rem If we have Python in externals, use that one
-@if exist "%_Py_EXTERNALS_DIR%\pythonx86\tools\python.exe" ("%_Py_EXTERNALS_DIR%\pythonx86\tools\python.exe" -Ec "import sys; assert sys.version_info[:2] >= (3, 10)" >nul 2>nul) && (set PYTHON="%_Py_EXTERNALS_DIR%\pythonx86\tools\python.exe") && (set _Py_Python_Source=found in externals directory) && goto :found || rmdir /Q /S "%_Py_EXTERNALS_DIR%\pythonx86"
+@if exist "%_Py_EXTERNALS_DIR%\pythonx86\tools\python.exe" ("%_Py_EXTERNALS_DIR%\pythonx86\tools\python.exe" -Ec "import sys; assert sys.version_info[:2] >= (3, 8)" >nul 2>nul) && (set PYTHON="%_Py_EXTERNALS_DIR%\pythonx86\tools\python.exe") && (set _Py_Python_Source=found in externals directory) && goto :found || rmdir /Q /S "%_Py_EXTERNALS_DIR%\pythonx86"
 
 @rem If HOST_PYTHON is recent enough, use that
-@if NOT "%HOST_PYTHON%"=="" @%HOST_PYTHON% -Ec "import sys; assert sys.version_info[:2] >= (3, 10)" >nul 2>nul && (set PYTHON="%HOST_PYTHON%") && (set _Py_Python_Source=found as HOST_PYTHON) && goto :found
+@if NOT "%HOST_PYTHON%"=="" @%HOST_PYTHON% -Ec "import sys; assert sys.version_info[:2] >= (3, 8)" >nul 2>nul && (set PYTHON="%HOST_PYTHON%") && (set _Py_Python_Source=found as HOST_PYTHON) && goto :found
 
 @rem If py.exe finds a recent enough version, use that one
-@for %%p in (3.10) do @py -%%p -EV >nul 2>&1 && (set PYTHON=py -%%p) && (set _Py_Python_Source=found %%p with py.exe) && goto :found
+@for %%p in (3.10 3.9 3.8) do @py -%%p -EV >nul 2>&1 && (set PYTHON=py -%%p) && (set _Py_Python_Source=found %%p with py.exe) && goto :found
 
 @if NOT exist "%_Py_EXTERNALS_DIR%" mkdir "%_Py_EXTERNALS_DIR%"
 @set _Py_NUGET=%NUGET%

PCbuild/find_python.bat

@@ -7,7 +7,7 @@
 import re
 import time
 import types
-import typing
+from typing import Dict, FrozenSet, Tuple, TextIO
 
 import umarshal
 
@@ -42,13 +42,14 @@ def get_localsplus(code: types.CodeType):
 
 
 def get_localsplus_counts(code: types.CodeType,
-                          names: tuple[str, ...],
-                          kinds: bytes) -> tuple[int, int, int, int]:
+                          names: Tuple[str, ...],
+                          kinds: bytes) -> Tuple[int, int, int, int]:
     nlocals = 0
     nplaincellvars = 0
     ncellvars = 0
     nfreevars = 0
-    for name, kind in zip(names, kinds, strict=True):
+    assert len(names) == len(kinds)
+    for name, kind in zip(names, kinds):
         if kind & CO_FAST_LOCAL:
             nlocals += 1
             if kind & CO_FAST_CELL:
@@ -71,7 +72,7 @@ def get_localsplus_counts(code: types.CodeType,
 PyUnicode_4BYTE_KIND = 4
 
 
-def analyze_character_width(s: str) -> tuple[int, bool]:
+def analyze_character_width(s: str) -> Tuple[int, bool]:
     maxchar = ' '
     for c in s:
         maxchar = max(maxchar, c)
@@ -86,12 +87,17 @@ def analyze_character_width(s: str) -> tuple[int, bool]:
     return kind, ascii
 
 
+def removesuffix(base: str, suffix: str) -> str:
+    if base.endswith(suffix):
+        return base[:len(base) - len(suffix)]
+    return base
+
 class Printer:
 
-    def __init__(self, file: typing.TextIO):
+    def __init__(self, file: TextIO):
         self.level = 0
         self.file = file
-        self.cache: dict[tuple[type, object], str] = {}
+        self.cache: Dict[Tuple[type, object], str] = {}
         self.hits, self.misses = 0, 0
         self.patchups: list[str] = []
         self.write('#include "Python.h"')
@@ -231,7 +237,7 @@ def generate_code(self, name: str, code: types.CodeType) -> str:
             # otherwise MSVC doesn't like it.
             self.write(f".co_consts = {co_consts},")
             self.write(f".co_names = {co_names},")
-            self.write(f".co_firstinstr = (_Py_CODEUNIT *) {co_code.removesuffix('.ob_base.ob_base')}.ob_sval,")
+            self.write(f".co_firstinstr = (_Py_CODEUNIT *) {removesuffix(co_code, '.ob_base.ob_base')}.ob_sval,")
             self.write(f".co_exceptiontable = {co_exceptiontable},")
             self.field(code, "co_flags")
             self.write(".co_warmup = QUICKENING_INITIAL_WARMUP_VALUE,")
@@ -259,7 +265,7 @@ def generate_code(self, name: str, code: types.CodeType) -> str:
             self.write(f".co_freevars = {co_freevars},")
         return f"& {name}.ob_base"
 
-    def generate_tuple(self, name: str, t: tuple[object, ...]) -> str:
+    def generate_tuple(self, name: str, t: Tuple[object, ...]) -> str:
         items = [self.generate(f"{name}_{i}", it) for i, it in enumerate(t)]
         self.write("static")
         with self.indent():
@@ -323,7 +329,7 @@ def generate_complex(self, name: str, z: complex) -> str:
             self.write(f".cval = {{ {z.real}, {z.imag} }},")
         return f"&{name}.ob_base"
 
-    def generate_frozenset(self, name: str, fs: frozenset[object]) -> str:
+    def generate_frozenset(self, name: str, fs: FrozenSet[object]) -> str:
         ret = self.generate_tuple(name, tuple(sorted(fs)))
         self.write("// TODO: The above tuple should be a frozenset")
         return ret
@@ -336,34 +342,33 @@ def generate(self, name: str, obj: object) -> str:
             # print(f"Cache hit {key!r:.40}: {self.cache[key]!r:.40}")
             return self.cache[key]
         self.misses += 1
-        match obj:
-            case types.CodeType() | umarshal.Code() as code:
-                val = self.generate_code(name, code)
-            case tuple(t):
-                val = self.generate_tuple(name, t)
-            case str(s):
-                val = self.generate_unicode(name, s)
-            case bytes(b):
-                val = self.generate_bytes(name, b)
-            case True:
-                return "Py_True"
-            case False:
-                return "Py_False"
-            case int(i):
-                val = self.generate_int(name, i)
-            case float(x):
-                val = self.generate_float(name, x)
-            case complex() as z:
-                val = self.generate_complex(name, z)
-            case frozenset(fs):
-                val = self.generate_frozenset(name, fs)
-            case builtins.Ellipsis:
-                return "Py_Ellipsis"
-            case None:
-                return "Py_None"
-            case _:
-                raise TypeError(
-                    f"Cannot generate code for {type(obj).__name__} object")
+        if isinstance(obj, types.CodeType) or isinstance(obj, umarshal.Code):
+            val = self.generate_code(name, obj)
+        elif isinstance(obj, tuple):
+            val = self.generate_tuple(name, obj)
+        elif isinstance(obj, str):
+            val = self.generate_unicode(name, obj)
+        elif isinstance(obj, bytes):
+            val = self.generate_bytes(name, obj)
+        elif obj is True:
+            return "Py_True"
+        elif obj is False:
+            return "Py_False"
+        elif isinstance(obj, int):
+            val = self.generate_int(name, obj)
+        elif isinstance(obj, float):
+            val = self.generate_float(name, obj)
+        elif isinstance(obj, complex):
+            val = self.generate_complex(name, obj)
+        elif isinstance(obj, frozenset):
+            val = self.generate_frozenset(name, obj)
+        elif obj is builtins.Ellipsis:
+            return "Py_Ellipsis"
+        elif obj is None:
+            return "Py_None"
+        else:
+            raise TypeError(
+                f"Cannot generate code for {type(obj).__name__} object")
         # print(f"Cache store {key!r:.40}: {val!r:.40}")
         self.cache[key] = val
         return val
@@ -393,12 +398,12 @@ def decode_frozen_data(source: str) -> types.CodeType:
         del lines[0]
     while lines and re.match(FROZEN_DATA_LINE, lines[-1]) is None:
         del lines[-1]
-    values: tuple[int, ...] = ast.literal_eval("".join(lines))
+    values: Tuple[int, ...] = ast.literal_eval("".join(lines).strip())
     data = bytes(values)
     return umarshal.loads(data)
 
 
-def generate(source: str, filename: str, modname: str, file: typing.TextIO) -> None:
+def generate(source: str, filename: str, modname: str, file: TextIO) -> None:
     if is_frozen_header(source):
         code = decode_frozen_data(source)
     else:
@@ -439,7 +444,7 @@ def main() -> None:
     verbose = args.verbose
     with open(args.file, encoding="utf-8") as f:
         source = f.read()
-    modname = args.module or os.path.basename(args.file).removesuffix(".py")
+    modname = args.module or removesuffix(os.path.basename(args.file), ".py")
     output = args.output or modname + ".c"
     with open(output, "w", encoding="utf-8") as file:
         with report_time("generate"):

Tools/scripts/deepfreeze.py

@@ -25,31 +25,6 @@
 # need to be updated.
 MODULES_DIR = os.path.join(ROOT_DIR, 'Python', 'frozen_modules')
 
-if sys.platform != "win32":
-    TOOL = os.path.join(ROOT_DIR, 'Programs', '_freeze_module')
-    if not os.path.isfile(TOOL):
-        # When building out of the source tree, get the tool from directory
-        # of the Python executable
-        TOOL = os.path.dirname(sys.executable)
-        TOOL = os.path.join(TOOL, 'Programs', '_freeze_module')
-        TOOL = os.path.abspath(TOOL)
-        if not os.path.isfile(TOOL):
-            sys.exit("ERROR: missing _freeze_module")
-else:
-    def find_tool():
-        archs = ['amd64', 'win32']
-        if platform.machine() == "ARM64":
-             archs.append('arm64')
-        for arch in archs:
-            for exe in ['_freeze_module.exe', '_freeze_module_d.exe']:
-                tool = os.path.join(ROOT_DIR, 'PCbuild', arch, exe)
-                if os.path.isfile(tool):
-                    return tool
-        sys.exit("ERROR: missing _freeze_module.exe; you need to run PCbuild/build.bat")
-    TOOL = find_tool()
-    del find_tool
-
-MANIFEST = os.path.join(MODULES_DIR, 'MANIFEST')
 FROZEN_FILE = os.path.join(ROOT_DIR, 'Python', 'frozen.c')
 MAKEFILE = os.path.join(ROOT_DIR, 'Makefile.pre.in')
 PCBUILD_PROJECT = os.path.join(ROOT_DIR, 'PCbuild', '_freeze_module.vcxproj')
@@ -480,45 +455,6 @@ def replace_block(lines, start_marker, end_marker, replacements, file):
     return lines[:start_pos + 1] + replacements + lines[end_pos:]
 
 
-def regen_manifest(modules):
-    header = 'module ispkg source frozen checksum'.split()
-    widths = [5] * len(header)
-    rows = []
-    for mod in modules:
-        info = mod.summarize()
-        row = []
-        for i, col in enumerate(header):
-            value = info[col]
-            if col == 'checksum':
-                value = value[:12]
-            elif col == 'ispkg':
-                value = 'YES' if value else 'no'
-            widths[i] = max(widths[i], len(value))
-            row.append(value or '-')
-        rows.append(row)
-
-    modlines = [
-        '# The list of frozen modules with key information.',
-        '# Note that the "check_generated_files" CI job will identify',
-        '# when source files were changed but regen-frozen wasn\'t run.',
-        '# This file is auto-generated by Tools/scripts/freeze_modules.py.',
-        ' '.join(c.center(w) for c, w in zip(header, widths)).rstrip(),
-        ' '.join('-' * w for w in widths),
-    ]
-    for row in rows:
-        for i, w in enumerate(widths):
-            if header[i] == 'ispkg':
-                row[i] = row[i].center(w)
-            else:
-                row[i] = row[i].ljust(w)
-        modlines.append(' '.join(row).rstrip())
-
-    print(f'# Updating {os.path.relpath(MANIFEST)}')
-    with open(MANIFEST, 'w', encoding="utf-8") as outfile:
-        lines = (l + '\n' for l in modlines)
-        outfile.writelines(lines)
-
-
 def regen_frozen(modules):
     headerlines = []
     parentdir = os.path.dirname(FROZEN_FILE)
@@ -648,11 +584,11 @@ def regen_makefile(modules):
         deepfreezefiles.append(f"\t\t{ofile} \\")
 
         # Also add a deepfreeze rule.
-        deepfreezerules.append(f'{cfile}: $(srcdir)/{_pyfile} $(DEEPFREEZE_DEPS)')
-        deepfreezerules.append(f'\t@echo "Deepfreezing {cfile} from {_pyfile}"')
-        deepfreezerules.append(f"\t@./$(BOOTSTRAP) \\")
-        deepfreezerules.append(f"\t\t$(srcdir)/Tools/scripts/deepfreeze.py \\")
-        deepfreezerules.append(f"\t\t$(srcdir)/{_pyfile} -m {src.frozenid} -o {cfile}")
+        deepfreezerules.append(f'{cfile}: {header} $(DEEPFREEZE_DEPS)')
+        deepfreezerules.append(
+            f"\t$(PYTHON_FOR_REGEN) "
+            f"$(srcdir)/Tools/scripts/deepfreeze.py "
+            f"{header} -m {src.frozenid} -o {cfile}")
         deepfreezerules.append('')
 
     for src in _iter_sources(modules):
@@ -663,7 +599,7 @@ def regen_makefile(modules):
         pyfiles.append(f'\t\t{pyfile} \\')
 
         freeze = (f'Programs/_freeze_module {src.frozenid} '
-                  f'$(srcdir)/{pyfile} $(srcdir)/{header}')
+                  f'$(srcdir)/{pyfile} {header}')
         rules.extend([
             f'{header}: Programs/_freeze_module {pyfile}',
             f'\t{freeze}',
@@ -774,32 +710,6 @@ def regen_pcbuild(modules):
         outfile.writelines(lines)
 
 
-#######################################
-# freezing modules
-
-def freeze_module(modname, pyfile=None, destdir=MODULES_DIR):
-    """Generate the frozen module .h file for the given module."""
-    tmpsuffix = f'.{int(time.time())}'
-    for modname, pyfile, ispkg in resolve_modules(modname, pyfile):
-        frozenfile = resolve_frozen_file(modname, destdir)
-        _freeze_module(modname, pyfile, frozenfile, tmpsuffix)
-
-
-def _freeze_module(frozenid, pyfile, frozenfile, tmpsuffix):
-    tmpfile = f'{frozenfile}.{int(time.time())}'
-
-    argv = [TOOL, frozenid, pyfile, tmpfile]
-    print('#', '  '.join(os.path.relpath(a) for a in argv), flush=True)
-    try:
-        subprocess.run(argv, check=True)
-    except (FileNotFoundError, subprocess.CalledProcessError):
-        if not os.path.exists(TOOL):
-            sys.exit(f'ERROR: missing {TOOL}; you need to run "make regen-frozen"')
-        raise  # re-raise
-
-    update_file_with_tmpfile(frozenfile, tmpfile, create=True)
-
-
 #######################################
 # the script
 
@@ -810,15 +720,7 @@ def main():
     # Regen build-related files.
     regen_makefile(modules)
     regen_pcbuild(modules)
-
-    # Freeze the target modules.
-    tmpsuffix = f'.{int(time.time())}'
-    for src in _iter_sources(modules):
-        _freeze_module(src.frozenid, src.pyfile, src.frozenfile, tmpsuffix)
-
-    # Regen files dependent of frozen file details.
     regen_frozen(modules)
-    regen_manifest(modules)
 
 
 if __name__ == '__main__':