3. Python を構成する

3.1. ビルド要件

CPython のビルドに必要な機能と最小バージョン:

• C11 コンパイラ。 C11 オプション機能 は不要です。

• Windows では、 Microsoft Visual Studio 2017 以降が必要です。

• Support for IEEE 754 floating-point numbers and floating-point Not-a-Number (NaN).

• Support for threads.

• OpenSSL 1.1.1 is the minimum version and OpenSSL 3.0.9 is the recommended minimum version for the ssl and hashlib extension modules.

• SQLite 3.15.2 for the sqlite3 extension module.

• Tcl/Tk 8.5.12 for the tkinter module.

• Autoconf 2.71 and aclocal 1.16.5 are required to regenerate the configure script.

バージョン 3.1 で変更: Tcl/Tk version 8.3.1 is now required.

バージョン 3.5 で変更: On Windows, Visual Studio 2015 or later is now required. Tcl/Tk version 8.4 is now required.

バージョン 3.6 で変更: Selected C99 features are now required, like <stdint.h> and static inline functions.

バージョン 3.7 で変更: Thread support and OpenSSL 1.0.2 are now required.

バージョン 3.10 で変更: OpenSSL 1.1.1 is now required. Require SQLite 3.7.15.

バージョン 3.11 で変更: C11 compiler, IEEE 754 and NaN support are now required. On Windows, Visual Studio 2017 or later is required. Tcl/Tk version 8.5.12 is now required for the tkinter module.

バージョン 3.13 で変更: Autoconf 2.71, aclocal 1.16.5 and SQLite 3.15.2 are now required.

See also PEP 7 "Style Guide for C Code" and PEP 11 "CPython platform support".

3.2. 生成されるファイル

To reduce build dependencies, Python source code contains multiple generated files. Commands to regenerate all generated files:

make regen-all
make regen-stdlib-module-names
make regen-limited-abi
make regen-configure

The Makefile.pre.in file documents generated files, their inputs, and tools used to regenerate them. Search for regen-* make targets.

3.2.1. 構成スクリプト

The make regen-configure command regenerates the aclocal.m4 file and the configure script using the Tools/build/regen-configure.sh shell script which uses an Ubuntu container to get the same tools versions and have a reproducible output.

The container is optional, the following command can be run locally:

autoreconf -ivf -Werror

The generated files can change depending on the exact autoconf-archive, aclocal and pkg-config versions.

3.3. Configureオプション

List all configure script options using:

./configure --help

Pythonのソース配布の中の Misc/SpecialBuilds.txt も参照してください。

3.3.1. 一般的なオプション

--enable-loadable-sqlite-extensions

Support loadable extensions in the _sqlite extension module (default is no) of the sqlite3 module.

sqlite3 モジュールの sqlite3.Connection.enable_load_extension() メソッドを参照してください。

Added in version 3.6.

--disable-ipv6

IPv6サポートを無効にします(サポートされている場合はデフォルトで有効)、 socket モジュールを参照してください。

--enable-big-digits=[15|30]

Python int の桁の大きさをビット単位で定義します: 15ビットまたは30ビットです。

デフォルトでは、桁の大きさは30です。

PYLONG_BITS_IN_DIGIT を 15 または 30 に定義します。

sys.int_info.bits_per_digit を参照してください。

--with-suffix=SUFFIX

Python の実行ファイルの接尾辞を SUFFIX に設定します。

デフォルトの接尾辞は、 Windows と macOS では .exe ( python.exe 実行ファイル)、 Emscripten node では .js 、 Emscripten browser では .html 、 WASI では .wasm 、その他のプラットフォームでは空文字列になります ( python 実行ファイル)。

バージョン 3.11 で変更: WASM プラットフォームのデフォルトの接頭辞は、 .js 、 .html 、 .wasm のうちの1つです。

--with-tzpath=<list of absolute paths separated by pathsep>

デフォルトのタイムゾーン検索パスを zoneinfo.TZPATH に設定します。zoneinfo モジュールの Compile-time configuration を参照してください。

デフォルト: /usr/share/zoneinfo:/usr/lib/zoneinfo:/usr/share/lib/zoneinfo:/etc/zoneinfo

os.pathsep パスセパレータを参照してください。

Added in version 3.9.

--without-decimal-contextvar

コルーチンローカルコンテキスト(デフォルト)ではなく、スレッドローカルコンテキストを使用して _decimal 拡張モジュールをビルドします。 decimal モジュールを参照してください。

decimal.HAVE_CONTEXTVAR および contextvars モジュールを参照してください。

Added in version 3.9.

--with-dbmliborder=<list of backend names>

dbm モジュールの DB バックエンドをチェックする順序をオーバーライドします。

有効な値は、バックエンド名をコロン( : )で区切った文字列です:

• ndbm;

• gdbm;

• bdb。

--without-c-locale-coercion

UTF-8 ベースのロケールへの C ロケールの強制を無効にします(デフォルトで有効)。

PY_COERCE_C_LOCALE マクロは定義しないでください。

PYTHONCOERCECLOCALE および PEP 538 を参照してください。

--without-freelists

Disable all freelists except the empty tuple singleton.

Added in version 3.11.

--with-platlibdir=DIRNAME

Python のライブラリディレクトリ名(デフォルトは lib )。

Fedora と SuSE は64ビットプラットフォームで lib64 を使用します。

sys.platlibdir を参照してください。

Added in version 3.9.

--with-wheel-pkg-dir=PATH

ensurepip モジュールが使用する wheel パッケージのディレクトリです(デフォルトはなし)。

Linux ディストリビューションのパッケージングポリシーの中には、依存関係をバンドルすることを推奨しているものがあります。例えば、 Fedora は wheel パッケージを /usr/share/python-wheels/ ディレクトリにインストールし、 ensurepip._bundled パッケージはインストールしません。

Added in version 3.10.

--with-pkg-config=[check|yes|no]

configure がビルドの依存関係を検出するために pkg-config を使用するかどうかを設定します。

• check (デフォルト): pkg-config はオプションです。

• yes : pkg-config は必須です。

• no : pkg-config が存在しても、 configure は使用しません。

Added in version 3.11.

--enable-pystats

Turn on internal Python performance statistics gathering.

By default, statistics gathering is off. Use python3 -X pystats command or set PYTHONSTATS=1 environment variable to turn on statistics gathering at Python startup.

At Python exit, dump statistics if statistics gathering was on and not cleared.

Effects:

• Add -X pystats command line option.

• Add PYTHONSTATS environment variable.

• Define the Py_STATS macro.

• Add functions to the sys module:

  • sys._stats_on(): Turns on statistics gathering.

  • sys._stats_off(): Turns off statistics gathering.

  • sys._stats_clear(): Clears the statistics.

  • sys._stats_dump(): Dump statistics to file, and clears the statistics.

The statistics will be dumped to a arbitrary (probably unique) file in /tmp/py_stats/ (Unix) or C:\temp\py_stats\ (Windows). If that directory does not exist, results will be printed on stderr.

統計情報を読むには Tools/scripts/summarize_stats.py を使用してください。

Statistics:

• Opcode:

  • Specialization: success, failure, hit, deferred, miss, deopt, failures;

  • Execution count;

  • Pair count.

• Call:

  • Inlined Python calls;

  • PyEval calls;

  • Frames pushed;

  • Frame object created;

  • Eval calls: vector, generator, legacy, function VECTORCALL, build class, slot, function "ex", API, method.

• Object:

  • incref and decref;

  • interpreter incref and decref;

  • allocations: all, 512 bytes, 4 kiB, big;

  • free;

  • to/from free lists;

  • dictionary materialized/dematerialized;

  • type cache;

  • optimization attempts;

  • optimization traces created/executed;

  • uops executed.

• Garbage collector:

  • Garbage collections;

  • Objects visited;

  • Objects collected.

Added in version 3.11.

--disable-gil

Enables experimental support for running Python without the global interpreter lock (GIL): free threading build.

Defines the Py_GIL_DISABLED macro and adds "t" to sys.abiflags.

See Free-threaded CPython for more detail.

Added in version 3.13.

--enable-experimental-jit=[no|yes|yes-off|interpreter]

Indicate how to integrate the JIT compiler.

• no - build the interpreter without the JIT.

• yes - build the interpreter with the JIT.

• yes-off - build the interpreter with the JIT but disable it by default.

• interpreter - build the interpreter without the JIT, but with the tier 2 enabled interpreter.

By convention, --enable-experimental-jit is a shorthand for --enable-experimental-jit=yes.

Added in version 3.13.

PKG_CONFIG

Path to pkg-config utility.

PKG_CONFIG_LIBDIR

PKG_CONFIG_PATH

pkg-config options.

3.3.2. C コンパイラのオプション

CC

C コンパイラのコマンド。

CFLAGS

C コンパイラのフラグ。

CPP

C プリプロセッサのコマンド。

CPPFLAGS

C プリプロセッサのフラグ。 (-Iinclude_dir など)

3.3.3. リンカのオプション

LDFLAGS

リンカのフラグ。 (-Llibrary_directory など)

LIBS

リンカに渡すライブラリ。 (-llibrary など)

MACHDEP

マシン依存のライブラリファイルの名前。

3.3.4. サードパーティ依存関係のオプション

Added in version 3.11.

BZIP2_CFLAGS

BZIP2_LIBS

C compiler and linker flags to link Python to libbz2, used by bz2 module, overriding pkg-config.

CURSES_CFLAGS

CURSES_LIBS

C compiler and linker flags for libncurses or libncursesw, used by curses module, overriding pkg-config.

GDBM_CFLAGS

GDBM_LIBS

C compiler and linker flags for gdbm.

LIBB2_CFLAGS

LIBB2_LIBS

C compiler and linker flags for libb2 (BLAKE2), used by hashlib module, overriding pkg-config.

LIBEDIT_CFLAGS

LIBEDIT_LIBS

C compiler and linker flags for libedit, used by readline module, overriding pkg-config.

LIBFFI_CFLAGS

LIBFFI_LIBS

C compiler and linker flags for libffi, used by ctypes module, overriding pkg-config.

LIBMPDEC_CFLAGS

LIBMPDEC_LIBS

C compiler and linker flags for libmpdec, used by decimal module, overriding pkg-config.

注釈

These environment variables have no effect unless --with-system-libmpdec is specified.

LIBLZMA_CFLAGS

LIBLZMA_LIBS

C compiler and linker flags for liblzma, used by lzma module, overriding pkg-config.

LIBREADLINE_CFLAGS

LIBREADLINE_LIBS

C compiler and linker flags for libreadline, used by readline module, overriding pkg-config.

LIBSQLITE3_CFLAGS

LIBSQLITE3_LIBS

C compiler and linker flags for libsqlite3, used by sqlite3 module, overriding pkg-config.

LIBUUID_CFLAGS

LIBUUID_LIBS

C compiler and linker flags for libuuid, used by uuid module, overriding pkg-config.

PANEL_CFLAGS

PANEL_LIBS

C compiler and linker flags for PANEL, overriding pkg-config.

C compiler and linker flags for libpanel or libpanelw, used by curses.panel module, overriding pkg-config.

TCLTK_CFLAGS

TCLTK_LIBS

C compiler and linker flags for TCLTK, overriding pkg-config.

ZLIB_CFLAGS

ZLIB_LIBS

C compiler and linker flags for libzlib, used by gzip module, overriding pkg-config.

3.3.5. WebAssembly オプション

--with-emscripten-target=[browser|node]

wasm32-emscripten のビルドフレーバーを設定します。

• browser (デフォルト): 最小限の stdlib 、デフォルトの MEMFS をプリロードします。

• node: NODERAWFS と pthread をサポートします。

Added in version 3.11.

--enable-wasm-dynamic-linking

WASM のダイナミックリンクサポートをオンにします。

ダイナミックリンクにより dlopen が可能になります。デッドコードの排除や機能追加に制限があるため、実行ファイルのファイルサイズが大きくなります。

Added in version 3.11.

--enable-wasm-pthreads

WASM の pthreads サポートをオンにします。

Added in version 3.11.

3.3.6. インストールオプション

--prefix=PREFIX

アーキテクチャに依存しないファイルを PREFIX にインストールします。Unix の場合、デフォルトは /usr/local です。

この値は、実行時に sys.prefix を使って取得することができます。

例として、 --prefix="$HOME/.local/" を使用すると、 Python をそのホームディレクトリにインストールすることができます。

--exec-prefix=EPREFIX

アーキテクチャ依存のファイルを EPREFIX にインストールします。デフォルトは --prefix です。

この値は、実行時に sys.exec_prefix を使って取得することができます。

--disable-test-modules

test パッケージや _testcapi 拡張モジュール(デフォルトでビルド、インストールされます)のようなテストモジュールをビルド、インストールしないようにします。

Added in version 3.10.

--with-ensurepip=[upgrade|install|no]

Python のインストール時に実行される ensurepip コマンドを選択します:

• upgrade (デフォルト): python -m ensurepip --altinstall --upgrade コマンドを実行します。

• install: python -m ensurepip --altinstall コマンドを実行します。

• no: ensurepip を実行しない;

Added in version 3.6.

3.3.7. パフォーマンスに関するオプション

Configuring Python using --enable-optimizations --with-lto (PGO + LTO) is recommended for best performance. The experimental --enable-bolt flag can also be used to improve performance.

--enable-optimizations

PROFILE_TASK を使用して Profile Guided Optimization (PGO) を有効にします(デフォルトでは無効です)。

Cコンパイラの Clang では、 PGO のために llvm-profdata プログラムが必要です。macOS では、 GCC もこれを必要とします: GCC は macOS の Clang のエイリアスにすぎません。

Disable also semantic interposition in libpython if --enable-shared and GCC is used: add -fno-semantic-interposition to the compiler and linker flags.

注釈

During the build, you may encounter compiler warnings about profile data not being available for some source files. These warnings are harmless, as only a subset of the code is exercised during profile data acquisition. To disable these warnings on Clang, manually suppress them by adding -Wno-profile-instr-unprofiled to CFLAGS.

Added in version 3.6.

バージョン 3.10 で変更: GCC で -fno-semantic-interposition を使用する。

PROFILE_TASK

Environment variable used in the Makefile: Python command line arguments for the PGO generation task.

デフォルト: -m test --pgo --timeout=$(TESTTIMEOUT)

Added in version 3.8.

バージョン 3.13 で変更: Task failure is no longer ignored silently.

--with-lto=[full|thin|no|yes]

Enable Link Time Optimization (LTO) in any build (disabled by default).

The C compiler Clang requires llvm-ar for LTO (ar on macOS), as well as an LTO-aware linker (ld.gold or lld).

Added in version 3.6.

Added in version 3.11: To use ThinLTO feature, use --with-lto=thin on Clang.

バージョン 3.12 で変更: Use ThinLTO as the default optimization policy on Clang if the compiler accepts the flag.

--enable-bolt

Enable usage of the BOLT post-link binary optimizer (disabled by default).

BOLT is part of the LLVM project but is not always included in their binary distributions. This flag requires that llvm-bolt and merge-fdata are available.

BOLT is still a fairly new project so this flag should be considered experimental for now. Because this tool operates on machine code its success is dependent on a combination of the build environment + the other optimization configure args + the CPU architecture, and not all combinations are supported. BOLT versions before LLVM 16 are known to crash BOLT under some scenarios. Use of LLVM 16 or newer for BOLT optimization is strongly encouraged.

The BOLT_INSTRUMENT_FLAGS and BOLT_APPLY_FLAGS configure variables can be defined to override the default set of arguments for llvm-bolt to instrument and apply BOLT data to binaries, respectively.

Added in version 3.12.

BOLT_APPLY_FLAGS

Arguments to llvm-bolt when creating a BOLT optimized binary.

Added in version 3.12.

BOLT_INSTRUMENT_FLAGS

Arguments to llvm-bolt when instrumenting binaries.

Added in version 3.12.

--with-computed-gotos

Enable computed gotos in evaluation loop (enabled by default on supported compilers).

--without-mimalloc

Disable the fast mimalloc allocator (enabled by default).

See also PYTHONMALLOC environment variable.

--without-pymalloc

Disable the specialized Python memory allocator pymalloc (enabled by default).

See also PYTHONMALLOC environment variable.

--without-doc-strings

Disable static documentation strings to reduce the memory footprint (enabled by default). Documentation strings defined in Python are not affected.

Don't define the WITH_DOC_STRINGS macro.

See the PyDoc_STRVAR() macro.

--enable-profiling

Enable C-level code profiling with gprof (disabled by default).

--with-strict-overflow

Add -fstrict-overflow to the C compiler flags (by default we add -fno-strict-overflow instead).

3.3.8. Python Debug Build

A debug build is Python built with the --with-pydebug configure option.

Effects of a debug build:

• Display all warnings by default: the list of default warning filters is empty in the warnings module.

• Add d to sys.abiflags.

• Add sys.gettotalrefcount() function.

• Add -X showrefcount command line option.

• Add -d command line option and PYTHONDEBUG environment variable to debug the parser.

• Add support for the __lltrace__ variable: enable low-level tracing in the bytecode evaluation loop if the variable is defined.

• Install debug hooks on memory allocators to detect buffer overflow and other memory errors.

• Define Py_DEBUG and Py_REF_DEBUG macros.

• Add runtime checks: code surrounded by #ifdef Py_DEBUG and #endif. Enable assert(...) and _PyObject_ASSERT(...) assertions: don't set the NDEBUG macro (see also the --with-assertions configure option). Main runtime checks:

  • Add sanity checks on the function arguments.

  • Unicode and int objects are created with their memory filled with a pattern to detect usage of uninitialized objects.

  • Ensure that functions which can clear or replace the current exception are not called with an exception raised.

  • Check that deallocator functions don't change the current exception.

  • The garbage collector (gc.collect() function) runs some basic checks on objects consistency.

  • The Py_SAFE_DOWNCAST() macro checks for integer underflow and overflow when downcasting from wide types to narrow types.

See also the Python Development Mode and the --with-trace-refs configure option.

バージョン 3.8 で変更: Release builds and debug builds are now ABI compatible: defining the Py_DEBUG macro no longer implies the Py_TRACE_REFS macro (see the --with-trace-refs option).

3.3.9. Debug options

--with-pydebug

Build Python in debug mode: define the Py_DEBUG macro (disabled by default).

--with-trace-refs

Enable tracing references for debugging purpose (disabled by default).

Effects:

• Define the Py_TRACE_REFS macro.

• Add sys.getobjects() function.

• Add PYTHONDUMPREFS environment variable.

The PYTHONDUMPREFS environment variable can be used to dump objects and reference counts still alive at Python exit.

Statically allocated objects are not traced.

Added in version 3.8.

バージョン 3.13 で変更: This build is now ABI compatible with release build and debug build.

--with-assertions

Build with C assertions enabled (default is no): assert(...); and _PyObject_ASSERT(...);.

If set, the NDEBUG macro is not defined in the OPT compiler variable.

See also the --with-pydebug option (debug build) which also enables assertions.

Added in version 3.6.

--with-valgrind

Enable Valgrind support (default is no).

--with-dtrace

Enable DTrace support (default is no).

See Instrumenting CPython with DTrace and SystemTap.

Added in version 3.6.

--with-address-sanitizer

Enable AddressSanitizer memory error detector, asan (default is no).

Added in version 3.6.

--with-memory-sanitizer

Enable MemorySanitizer allocation error detector, msan (default is no).

Added in version 3.6.

--with-undefined-behavior-sanitizer

Enable UndefinedBehaviorSanitizer undefined behaviour detector, ubsan (default is no).

Added in version 3.6.

--with-thread-sanitizer

Enable ThreadSanitizer data race detector, tsan (default is no).

Added in version 3.13.

3.3.10. リンカのオプション

--enable-shared

Enable building a shared Python library: libpython (default is no).

--without-static-libpython

Do not build libpythonMAJOR.MINOR.a and do not install python.o (built and enabled by default).

Added in version 3.10.

3.3.11. Libraries options

--with-libs='lib1 ...'

Link against additional libraries (default is no).

--with-system-expat

Build the pyexpat module using an installed expat library (default is no).

--with-system-libmpdec

Build the _decimal extension module using an installed mpdecimal library, see the decimal module (default is yes).

Added in version 3.3.

バージョン 3.13 で変更: Default to using the installed mpdecimal library.

Deprecated since version 3.13, will be removed in version 3.15: A copy of the mpdecimal library sources will no longer be distributed with Python 3.15.

参考

LIBMPDEC_CFLAGS and LIBMPDEC_LIBS.

--with-readline=readline|editline

Designate a backend library for the readline module.

• readline: Use readline as the backend.

• editline: Use editline as the backend.

Added in version 3.10.

--without-readline

Don't build the readline module (built by default).

Don't define the HAVE_LIBREADLINE macro.

Added in version 3.10.

--with-libm=STRING

Override libm math library to STRING (default is system-dependent).

--with-libc=STRING

Override libc C library to STRING (default is system-dependent).

--with-openssl=DIR

Root of the OpenSSL directory.

Added in version 3.7.

--with-openssl-rpath=[no|auto|DIR]

Set runtime library directory (rpath) for OpenSSL libraries:

• no (default): don't set rpath;

• auto: auto-detect rpath from --with-openssl and pkg-config;

• DIR: set an explicit rpath.

Added in version 3.10.

3.3.12. Security Options

--with-hash-algorithm=[fnv|siphash13|siphash24]

Select hash algorithm for use in Python/pyhash.c:

• siphash13 (default);

• siphash24;

• fnv.

Added in version 3.4.

Added in version 3.11: siphash13 is added and it is the new default.

--with-builtin-hashlib-hashes=md5,sha1,sha256,sha512,sha3,blake2

Built-in hash modules:

• md5;

• sha1;

• sha256;

• sha512;

• sha3 (with shake);

• blake2.

Added in version 3.9.

--with-ssl-default-suites=[python|openssl|STRING]

Override the OpenSSL default cipher suites string:

• python (default): use Python's preferred selection;

• openssl: leave OpenSSL's defaults untouched;

• STRING: use a custom string

See the ssl module.

Added in version 3.7.

バージョン 3.10 で変更: The settings python and STRING also set TLS 1.2 as minimum protocol version.

3.3.13. macOS のオプション

Mac/README.rst を参照。

--enable-universalsdk

--enable-universalsdk=SDKDIR

ユニバーサルバイナリビルドを作成します。 SDKDIR はビルドの実行にどの macOS SDK が使用されるべきかを指定します (デフォルトでは指定しません) 。

--enable-framework

--enable-framework=INSTALLDIR

従来の Unix インストールではなく、 Python.framework を作成します。オプションの INSTALLDIR はインストール先のパスを指定します (デフォルトでは指定しません) 。

--with-universal-archs=ARCH

作成するユニバーサルバイナリの種類を指定します。このオプションは、 --enable-universalsdk が指定された場合のみ有効です。

オプション:

• universal2;

• 32-bit;

• 64-bit;

• 3-way;

• intel;

• intel-32;

• intel-64;

• all。

--with-framework-name=FRAMEWORK

macOS の Python フレームワークの名前を指定します。 --enable-framework が指定された場合のみ有効です (デフォルトでは Python) 。

--with-app-store-compliance

--with-app-store-compliance=PATCH-FILE

Python 標準ライブラリは、 macOS と iOS の App Store による配布用に送信された場合に、自動検査ツールのエラーを発生させることが知られている文字列を含んでいます。このオプションを有効にした場合、 App Store コンプライアンスに合わせて修正することが知られているパッチのリストを適用します。カスタムのパッチファイルを指定することもできます。このオプションはデフォルトでは無効になっています。

Added in version 3.13.

3.3.14. iOS のオプション

iOS/README.rst を参照。

--enable-framework=INSTALLDIR

Python.framework を作成します。 macOS とは違い、インストールパスを指定する INSTALLDIR 引数は必須です。

--with-framework-name=FRAMEWORK

フレームワークの名前を指定します (デフォルト: Python) 。

3.3.15. クロスコンパイルのオプション

クロスコンパイル、またはクロスビルドは、異なる CPU アーキテクチャやプラットフォーム用に Python をビルドするために使用できます。クロスコンパイルには、ビルドプラットフォーム用の Python インタープリターが必要です。ビルドする Python のバージョンは、クロスコンパイルされたホスト Python のバージョンと一致する必要があります。

--build=BUILD

BUILD でビルドするための設定です。通常は、 config.guess により推測されます。

--host=HOST

HOST (ターゲットプラットフォーム) で動作するプログラムをビルドするためのクロスコンパイル。

--with-build-python=path/to/python

クロスコンパイル用のビルド python バイナリへのパス。

Added in version 3.11.

CONFIG_SITE=file

構成をオーバーライドするファイルを指す環境変数。

config.site ファイルの例:

# config.site-aarch64
ac_cv_buggy_getaddrinfo=no
ac_cv_file__dev_ptmx=yes
ac_cv_file__dev_ptc=no

HOSTRUNNER

クロスコンパイル用にホストプラットフォームの CPython を実行するプログラム。

Added in version 3.11.

クロスコンパイルの例:

CONFIG_SITE=config.site-aarch64 ../configure \
    --build=x86_64-pc-linux-gnu \
    --host=aarch64-unknown-linux-gnu \
    --with-build-python=../x86_64/python

3.4. Python ビルドシステム

3.4.1. ビルドシステムの主要なファイル

• configure.ac => configure;

• Makefile.pre.in => Makefile (configure により作成されます);

• pyconfig.h (configure により作成されます);

• Modules/Setup: Module/makesetup シェルスクリプトを使用して Makefile がビルドする C 拡張。

3.4.2. 主要なビルドステップ

• C files (.c) are built as object files (.o).

• A static libpython library (.a) is created from objects files.

• python.o and the static libpython library are linked into the final python program.

• C extensions are built by the Makefile (see Modules/Setup).

3.4.3. Main Makefile targets

3.4.3.1. make

For the most part, when rebuilding after editing some code or refreshing your checkout from upstream, all you need to do is execute make, which (per Make's semantics) builds the default target, the first one defined in the Makefile. By tradition (including in the CPython project) this is usually the all target. The configure script expands an autoconf variable, @DEF_MAKE_ALL_RULE@ to describe precisely which targets make all will build. The three choices are:

• profile-opt (configured with --enable-optimizations)

• build_wasm (configured with --with-emscripten-target)

• build_all (configured without explicitly using either of the others)

Depending on the most recent source file changes, Make will rebuild any targets (object files and executables) deemed out-of-date, including running configure again if necessary. Source/target dependencies are many and maintained manually however, so Make sometimes doesn't have all the information necessary to correctly detect all targets which need to be rebuilt. Depending on which targets aren't rebuilt, you might experience a number of problems. If you have build or test problems which you can't otherwise explain, make clean && make should work around most dependency problems, at the expense of longer build times.

3.4.3.2. make platform

Build the python program, but don't build the standard library extension modules. This generates a file named platform which contains a single line describing the details of the build platform, e.g., macosx-14.3-arm64-3.12 or linux-x86_64-3.13.

3.4.3.3. make profile-opt

Build Python using profile-guided optimization (PGO). You can use the configure --enable-optimizations option to make this the default target of the make command (make all or just make).

3.4.3.4. make clean

Remove built files.

3.4.3.5. make distclean

In addition to the work done by make clean, remove files created by the configure script. configure will have to be run before building again. [1]

3.4.3.6. make install

Build the all target and install Python.

3.4.3.7. make test

Build the all target and run the Python test suite with the --fast-ci option. Variables:

• TESTOPTS: additional regrtest command-line options.

• TESTPYTHONOPTS: additional Python command-line options.

• TESTTIMEOUT: timeout in seconds (default: 10 minutes).

3.4.3.8. make buildbottest

This is similar to make test, but uses the --slow-ci option and default timeout of 20 minutes, instead of --fast-ci option.

3.4.3.9. make regen-all

Regenerate (almost) all generated files. These include (but are not limited to) bytecode cases, and parser generator file. make regen-stdlib-module-names and autoconf must be run separately for the remaining generated files.

3.4.4. C extensions

Some C extensions are built as built-in modules, like the sys module. They are built with the Py_BUILD_CORE_BUILTIN macro defined. Built-in modules have no __file__ attribute:

>>> import sys
>>> sys
<module 'sys' (built-in)>
>>> sys.__file__
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
AttributeError: module 'sys' has no attribute '__file__'

Other C extensions are built as dynamic libraries, like the _asyncio module. They are built with the Py_BUILD_CORE_MODULE macro defined. Example on Linux x86-64:

>>> import _asyncio
>>> _asyncio
<module '_asyncio' from '/usr/lib64/python3.9/lib-dynload/_asyncio.cpython-39-x86_64-linux-gnu.so'>
>>> _asyncio.__file__
'/usr/lib64/python3.9/lib-dynload/_asyncio.cpython-39-x86_64-linux-gnu.so'

Modules/Setup is used to generate Makefile targets to build C extensions. At the beginning of the files, C extensions are built as built-in modules. Extensions defined after the *shared* marker are built as dynamic libraries.

The PyAPI_FUNC(), PyAPI_DATA() and PyMODINIT_FUNC macros of Include/exports.h are defined differently depending if the Py_BUILD_CORE_MODULE macro is defined:

• Use Py_EXPORTED_SYMBOL if the Py_BUILD_CORE_MODULE is defined

• Use Py_IMPORTED_SYMBOL otherwise.

If the Py_BUILD_CORE_BUILTIN macro is used by mistake on a C extension built as a shared library, its PyInit_xxx() function is not exported, causing an ImportError on import.

3.5. Compiler and linker flags

Options set by the ./configure script and environment variables and used by Makefile.

3.5.1. Preprocessor flags

CONFIGURE_CPPFLAGS

Value of CPPFLAGS variable passed to the ./configure script.

Added in version 3.6.

CPPFLAGS

(Objective) C/C++ preprocessor flags, e.g. -Iinclude_dir if you have headers in a nonstandard directory include_dir.

Both CPPFLAGS and LDFLAGS need to contain the shell's value to be able to build extension modules using the directories specified in the environment variables.

BASECPPFLAGS

Added in version 3.4.

PY_CPPFLAGS

Extra preprocessor flags added for building the interpreter object files.

Default: $(BASECPPFLAGS) -I. -I$(srcdir)/Include $(CONFIGURE_CPPFLAGS) $(CPPFLAGS).

Added in version 3.2.

3.5.2. Compiler flags

CC

C コンパイラのコマンド。

Example: gcc -pthread.

CXX

C++ compiler command.

Example: g++ -pthread.

CFLAGS

C コンパイラのフラグ。

CFLAGS_NODIST

CFLAGS_NODIST is used for building the interpreter and stdlib C extensions. Use it when a compiler flag should not be part of CFLAGS once Python is installed (gh-65320).

In particular, CFLAGS should not contain:

• the compiler flag -I (for setting the search path for include files). The -I flags are processed from left to right, and any flags in CFLAGS would take precedence over user- and package-supplied -I flags.

• hardening flags such as -Werror because distributions cannot control whether packages installed by users conform to such heightened standards.

Added in version 3.5.

COMPILEALL_OPTS

Options passed to the compileall command line when building PYC files in make install. Default: -j0.

Added in version 3.12.

EXTRA_CFLAGS

Extra C compiler flags.

CONFIGURE_CFLAGS

Value of CFLAGS variable passed to the ./configure script.

Added in version 3.2.

CONFIGURE_CFLAGS_NODIST

Value of CFLAGS_NODIST variable passed to the ./configure script.

Added in version 3.5.

BASECFLAGS

Base compiler flags.

OPT

Optimization flags.

CFLAGS_ALIASING

Strict or non-strict aliasing flags used to compile Python/dtoa.c.

Added in version 3.7.

CCSHARED

Compiler flags used to build a shared library.

For example, -fPIC is used on Linux and on BSD.

CFLAGSFORSHARED

Extra C flags added for building the interpreter object files.

Default: $(CCSHARED) when --enable-shared is used, or an empty string otherwise.

PY_CFLAGS

Default: $(BASECFLAGS) $(OPT) $(CONFIGURE_CFLAGS) $(CFLAGS) $(EXTRA_CFLAGS).

PY_CFLAGS_NODIST

Default: $(CONFIGURE_CFLAGS_NODIST) $(CFLAGS_NODIST) -I$(srcdir)/Include/internal.

Added in version 3.5.

PY_STDMODULE_CFLAGS

C flags used for building the interpreter object files.

Default: $(PY_CFLAGS) $(PY_CFLAGS_NODIST) $(PY_CPPFLAGS) $(CFLAGSFORSHARED).

Added in version 3.7.

PY_CORE_CFLAGS

Default: $(PY_STDMODULE_CFLAGS) -DPy_BUILD_CORE.

Added in version 3.2.

PY_BUILTIN_MODULE_CFLAGS

Compiler flags to build a standard library extension module as a built-in module, like the posix module.

Default: $(PY_STDMODULE_CFLAGS) -DPy_BUILD_CORE_BUILTIN.

Added in version 3.8.

PURIFY

Purify command. Purify is a memory debugger program.

Default: empty string (not used).

3.5.3. Linker flags

LINKCC

Linker command used to build programs like python and _testembed.

Default: $(PURIFY) $(CC).

CONFIGURE_LDFLAGS

Value of LDFLAGS variable passed to the ./configure script.

Avoid assigning CFLAGS, LDFLAGS, etc. so users can use them on the command line to append to these values without stomping the pre-set values.

Added in version 3.2.

LDFLAGS_NODIST

LDFLAGS_NODIST is used in the same manner as CFLAGS_NODIST. Use it when a linker flag should not be part of LDFLAGS once Python is installed (gh-65320).

In particular, LDFLAGS should not contain:

• the compiler flag -L (for setting the search path for libraries). The -L flags are processed from left to right, and any flags in LDFLAGS would take precedence over user- and package-supplied -L flags.

CONFIGURE_LDFLAGS_NODIST

Value of LDFLAGS_NODIST variable passed to the ./configure script.

Added in version 3.8.

LDFLAGS

Linker flags, e.g. -Llib_dir if you have libraries in a nonstandard directory lib_dir.

Both CPPFLAGS and LDFLAGS need to contain the shell's value to be able to build extension modules using the directories specified in the environment variables.

LIBS

Linker flags to pass libraries to the linker when linking the Python executable.

Example: -lrt.

LDSHARED

Command to build a shared library.

Default: @LDSHARED@ $(PY_LDFLAGS).

BLDSHARED

Command to build libpython shared library.

Default: @BLDSHARED@ $(PY_CORE_LDFLAGS).

PY_LDFLAGS

Default: $(CONFIGURE_LDFLAGS) $(LDFLAGS).

PY_LDFLAGS_NODIST

Default: $(CONFIGURE_LDFLAGS_NODIST) $(LDFLAGS_NODIST).

Added in version 3.8.

PY_CORE_LDFLAGS

Linker flags used for building the interpreter object files.

Added in version 3.8.

脚注

[1]

git clean -fdx is an even more extreme way to "clean" your checkout. It removes all files not known to Git. When bug hunting using git bisect, this is recommended between probes to guarantee a completely clean build. Use with care, as it will delete all files not checked into Git, including your new, uncommitted work.