python_doc_md/Beginner/using/configure.md

Configure Python

Build Requirements

To build CPython, you will need:

• A C11 compiler. Optional C11 features are not required.
• On Windows, Microsoft Visual Studio 2017 or later is required.
• Support for IEEE 754 floating-point numbers and floating-point Not-a-Number (NaN).
• Support for threads.

::: versionchanged 3.5 On Windows, Visual Studio 2015 or later is now required. :::

::: versionchanged 3.6 Selected C99 features, like <stdint.h> and static inline functions, are now required. :::

::: versionchanged 3.7 Thread support is now required. :::

::: versionchanged 3.11 C11 compiler, IEEE 754 and NaN support are now required. On Windows, Visual Studio 2017 or later is required. :::

See also 7{.interpreted-text role="pep"} "Style Guide for C Code" and 11{.interpreted-text role="pep"} "CPython platform support".

Requirements for optional modules {#optional-module-requirements}

Some optional modules <optional module>{.interpreted-text role="term"} of the standard library require third-party libraries installed for development (for example, header files must be available).

Missing requirements are reported in the configure output. Modules that are missing due to missing dependencies are listed near the end of the make output, sometimes using an internal name, for example, _ctypes for ctypes{.interpreted-text role="mod"} module.

If you distribute a CPython interpreter without optional modules, it's best practice to advise users, who generally expect that standard library modules are available.

Dependencies to build optional modules are:

+-------------------------------------------------------------------------------------------------------------------------+----------------------+------------------------------------------------------------------------------------------------------------------------------+ | Dependency | Minimum version | Python module | +=========================================================================================================================+======================+==============================================================================================================================+ | libbz2 | | bz2{.interpreted-text role="mod"} | +-------------------------------------------------------------------------------------------------------------------------+----------------------+------------------------------------------------------------------------------------------------------------------------------+ | libffi | 3.3.0 recommended | ctypes{.interpreted-text role="mod"} | +-------------------------------------------------------------------------------------------------------------------------+----------------------+------------------------------------------------------------------------------------------------------------------------------+ | liblzma | | lzma{.interpreted-text role="mod"} | +-------------------------------------------------------------------------------------------------------------------------+----------------------+------------------------------------------------------------------------------------------------------------------------------+ | libmpdec | 2.5.0 | decimal{.interpreted-text role="mod"}[^1] | +-------------------------------------------------------------------------------------------------------------------------+----------------------+------------------------------------------------------------------------------------------------------------------------------+ | libreadline or libedit[^2] | | readline{.interpreted-text role="mod"} | +-------------------------------------------------------------------------------------------------------------------------+----------------------+------------------------------------------------------------------------------------------------------------------------------+ | libuuid | | _uuid[^3] | +-------------------------------------------------------------------------------------------------------------------------+----------------------+------------------------------------------------------------------------------------------------------------------------------+ | ncurses[^4] | | curses{.interpreted-text role="mod"} | +-------------------------------------------------------------------------------------------------------------------------+----------------------+------------------------------------------------------------------------------------------------------------------------------+ | OpenSSL | | 3.0.18 recommended | ssl{.interpreted-text role="mod"}, hashlib{.interpreted-text role="mod"}[^5] | | | | (1.1.1 minimum) | | +-------------------------------------------------------------------------------------------------------------------------+----------------------+------------------------------------------------------------------------------------------------------------------------------+ | SQLite | 3.15.2 | sqlite3{.interpreted-text role="mod"} | +-------------------------------------------------------------------------------------------------------------------------+----------------------+------------------------------------------------------------------------------------------------------------------------------+ | Tcl/Tk | 8.5.12 | tkinter{.interpreted-text role="mod"}, IDLE <idle>{.interpreted-text role="ref"}, turtle{.interpreted-text role="mod"} | +-------------------------------------------------------------------------------------------------------------------------+----------------------+------------------------------------------------------------------------------------------------------------------------------+ | zlib | 1.2.2.1 | zlib{.interpreted-text role="mod"}, gzip{.interpreted-text role="mod"}, ensurepip{.interpreted-text role="mod"} | +-------------------------------------------------------------------------------------------------------------------------+----------------------+------------------------------------------------------------------------------------------------------------------------------+ | zstd | 1.4.5 | compression.zstd{.interpreted-text role="mod"} | +-------------------------------------------------------------------------------------------------------------------------+----------------------+------------------------------------------------------------------------------------------------------------------------------+

Note that the table does not include all optional modules; in particular, platform-specific modules like winreg{.interpreted-text role="mod"} are not listed here.

::: seealso

• The devguide includes a full list of dependencies required to build all modules and instructions on how to install them on common platforms.
• --with-system-expat{.interpreted-text role="option"} allows building with an external libexpat library.
• configure-options-for-dependencies{.interpreted-text role="ref"} :::

::: versionchanged 3.1 Tcl/Tk version 8.3.1 is now required for tkinter{.interpreted-text role="mod"}. :::

::: versionchanged 3.5 Tcl/Tk version 8.4 is now required for tkinter{.interpreted-text role="mod"}. :::

::: versionchanged 3.7 OpenSSL 1.0.2 is now required for hashlib{.interpreted-text role="mod"} and ssl{.interpreted-text role="mod"}. :::

::: versionchanged 3.10 OpenSSL 1.1.1 is now required for hashlib{.interpreted-text role="mod"} and ssl{.interpreted-text role="mod"}. SQLite 3.7.15 is now required for sqlite3{.interpreted-text role="mod"}. :::

::: versionchanged 3.11 Tcl/Tk version 8.5.12 is now required for tkinter{.interpreted-text role="mod"}. :::

::: versionchanged 3.13 SQLite 3.15.2 is now required for sqlite3{.interpreted-text role="mod"}. :::

Generated files

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.

configure script

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 versions of the tools used. The container that CPython uses has Autoconf 2.72, aclocal from Automake 1.16.5, and pkg-config 1.8.1.

::: versionchanged 3.13 Autoconf 2.71 and aclocal 1.16.5 and are now used to regenerate configure{.interpreted-text role="file"}. :::

::: versionchanged 3.14 Autoconf 2.72 is now used to regenerate configure{.interpreted-text role="file"}. :::

Configure Options

List all configure{.interpreted-text role="file"} script options using:

./configure --help

See also the Misc/SpecialBuilds.txt{.interpreted-text role="file"} in the Python source distribution.

General Options

:::: option

--enable-loadable-sqlite-extensions

:

Support loadable extensions in the !_sqlite{.interpreted-text role="mod"} extension module (default is no) of the sqlite3{.interpreted-text role="mod"} module.

See the sqlite3.Connection.enable_load_extension{.interpreted-text role="meth"} method of the sqlite3{.interpreted-text role="mod"} module.

::: versionadded 3.6 ::: ::::

::: option

--disable-ipv6

:

Disable IPv6 support (enabled by default if supported), see the socket{.interpreted-text role="mod"} module. :::

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

Define the size in bits of Python int{.interpreted-text role="class"} digits: 15 or 30 bits.

By default, the digit size is 30.

Define the PYLONG_BITS_IN_DIGIT to 15 or 30.

See sys.int_info.bits_per_digit <sys.int_info>{.interpreted-text role="data"}. :::

:::: option

--with-suffix=SUFFIX

:

Set the Python executable suffix to SUFFIX.

The default suffix is .exe on Windows and macOS (python.exe executable), .js on Emscripten node, .html on Emscripten browser, .wasm on WASI, and an empty string on other platforms (python executable).

::: versionchanged 3.11 The default suffix on WASM platform is one of .js, .html or .wasm. ::: ::::

:::: option

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

:

Select the default time zone search path for zoneinfo.TZPATH{.interpreted-text role="const"}. See the Compile-time configuration <zoneinfo_data_compile_time_config>{.interpreted-text role="ref"} of the zoneinfo{.interpreted-text role="mod"} module.

Default: /usr/share/zoneinfo:/usr/lib/zoneinfo:/usr/share/lib/zoneinfo:/etc/zoneinfo.

See os.pathsep{.interpreted-text role="data"} path separator.

::: versionadded 3.9 ::: ::::

:::: option

--without-decimal-contextvar

:

Build the _decimal extension module using a thread-local context rather than a coroutine-local context (default), see the decimal{.interpreted-text role="mod"} module.

See decimal.HAVE_CONTEXTVAR{.interpreted-text role="const"} and the contextvars{.interpreted-text role="mod"} module.

::: versionadded 3.9 ::: ::::

::: option

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

:

Override order to check db backends for the dbm{.interpreted-text role="mod"} module

A valid value is a colon (:) separated string with the backend names:

• ndbm;
• gdbm;
• bdb. :::

::: option

--without-c-locale-coercion

:

Disable C locale coercion to a UTF-8 based locale (enabled by default).

Don't define the PY_COERCE_C_LOCALE macro.

See PYTHONCOERCECLOCALE{.interpreted-text role="envvar"} and the 538{.interpreted-text role="pep"}. :::

:::: option

--with-platlibdir=DIRNAME

:

Python library directory name (default is lib).

Fedora and SuSE use lib64 on 64-bit platforms.

See sys.platlibdir{.interpreted-text role="data"}.

::: versionadded 3.9 ::: ::::

:::: option

--with-wheel-pkg-dir=PATH

:

Directory of wheel packages used by the ensurepip{.interpreted-text role="mod"} module (none by default).

Some Linux distribution packaging policies recommend against bundling dependencies. For example, Fedora installs wheel packages in the /usr/share/python-wheels/ directory and don't install the !ensurepip._bundled{.interpreted-text role="mod"} package.

::: versionadded 3.10 ::: ::::

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

Whether configure should use pkg-config{.interpreted-text role="program"} to detect build dependencies.

• check (default): pkg-config{.interpreted-text role="program"} is optional
• yes: pkg-config{.interpreted-text role="program"} is mandatory
• no: configure does not use pkg-config{.interpreted-text role="program"} even when present

::: versionadded 3.11 ::: ::::

:::: option

--with-missing-stdlib-config=FILE

:

Path to a JSON configuration file containing custom error messages for missing standard library{.interpreted-text role="term"} modules.

This option is intended for Python distributors who wish to provide distribution-specific guidance when users encounter standard library modules that are missing or packaged separately.

The JSON file should map missing module names to custom error message strings. For example, if your distribution packages tkinter{.interpreted-text role="mod"} and _tkinter{.interpreted-text role="mod"} separately and excludes !_gdbm{.interpreted-text role="mod"} for legal reasons, the configuration could contain:

{
    "_gdbm": "The '_gdbm' module is not available in this distribution",
    "tkinter": "Install the python-tk package to use tkinter",
    "_tkinter": "Install the python-tk package to use tkinter",
}

::: versionadded 3.15 ::: ::::

:::: option

--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 <-X>{.interpreted-text role="option"} command line option.
• Add !PYTHONSTATS{.interpreted-text role="envvar"} environment variable.
• Define the Py_STATS macro.
• Add functions to the sys{.interpreted-text role="mod"} module:
  • !sys._stats_on{.interpreted-text role="func"}: Turns on statistics gathering.
  • !sys._stats_off{.interpreted-text role="func"}: Turns off statistics gathering.
  • !sys._stats_clear{.interpreted-text role="func"}: Clears the statistics.
  • !sys._stats_dump{.interpreted-text role="func"}: 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.

Use Tools/scripts/summarize_stats.py to read the stats.

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.

::: versionadded 3.11 ::: ::::

::::: {#free-threading-build} :::: option

--disable-gil

:

Enables support for running Python without the global interpreter lock{.interpreted-text role="term"} (GIL): free-threaded build{.interpreted-text role="term"}.

Defines the Py_GIL_DISABLED macro and adds "t" to sys.abiflags{.interpreted-text role="data"}.

See whatsnew313-free-threaded-cpython{.interpreted-text role="ref"} for more detail.

::: versionadded 3.13 ::: :::: :::::

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

Indicate how to integrate the experimental just-in-time compiler <whatsnew314-jit-compiler>{.interpreted-text role="ref"}.

• no: Don't build the JIT.
• yes: Enable the JIT. To disable it at runtime, set the environment variable PYTHON_JIT=0 <PYTHON_JIT>{.interpreted-text role="envvar"}.
• yes-off: Build the JIT, but disable it by default. To enable it at runtime, set the environment variable PYTHON_JIT=1 <PYTHON_JIT>{.interpreted-text role="envvar"}.
• interpreter: Enable the "JIT interpreter" (only useful for those debugging the JIT itself). To disable it at runtime, set the environment variable PYTHON_JIT=0 <PYTHON_JIT>{.interpreted-text role="envvar"}.

--enable-experimental-jit=no is the default behavior if the option is not provided, and --enable-experimental-jit is shorthand for --enable-experimental-jit=yes. See Tools/jit/README.md{.interpreted-text role="file"} for more information, including how to install the necessary build-time dependencies.

:::: note ::: title Note :::

When building CPython with JIT enabled, ensure that your system has Python 3.11 or later installed. ::::

::: versionadded 3.13 ::: ::::::

::: option PKG_CONFIG

Path to pkg-config utility. :::

::: option PKG_CONFIG_LIBDIR :::

::: option PKG_CONFIG_PATH

pkg-config options. :::

C compiler options

::: option CC

C compiler command. :::

::: option CFLAGS

C compiler flags. :::

::: option CPP

C preprocessor command. :::

::: option CPPFLAGS

C preprocessor flags, e.g. -I{include_dir}{.interpreted-text role="samp"}. :::

Linker options

::: option LDFLAGS

Linker flags, e.g. -L{library_directory}{.interpreted-text role="samp"}. :::

::: option LIBS

Libraries to pass to the linker, e.g. -l{library}{.interpreted-text role="samp"}. :::

::: option MACHDEP

Name for machine-dependent library files. :::

Options for third-party dependencies {#configure-options-for-dependencies}

::: versionadded 3.11 :::

::: option BZIP2_CFLAGS :::

::: option BZIP2_LIBS

C compiler and linker flags to link Python to libbz2, used by bz2{.interpreted-text role="mod"} module, overriding pkg-config. :::

::: option CURSES_CFLAGS :::

::: option CURSES_LIBS

C compiler and linker flags for libncurses or libncursesw, used by curses{.interpreted-text role="mod"} module, overriding pkg-config. :::

::: option GDBM_CFLAGS :::

::: option GDBM_LIBS

C compiler and linker flags for gdbm. :::

::: option LIBEDIT_CFLAGS :::

::: option LIBEDIT_LIBS

C compiler and linker flags for libedit, used by readline{.interpreted-text role="mod"} module, overriding pkg-config. :::

::: option LIBFFI_CFLAGS :::

::: option LIBFFI_LIBS

C compiler and linker flags for libffi, used by ctypes{.interpreted-text role="mod"} module, overriding pkg-config. :::

::: option LIBMPDEC_CFLAGS :::

::::: option LIBMPDEC_LIBS

C compiler and linker flags for libmpdec, used by decimal{.interpreted-text role="mod"} module, overriding pkg-config.

:::: note ::: title Note :::

These environment variables have no effect unless --with-system-libmpdec{.interpreted-text role="option"} is specified. :::: :::::

::: option LIBLZMA_CFLAGS :::

::: option LIBLZMA_LIBS

C compiler and linker flags for liblzma, used by lzma{.interpreted-text role="mod"} module, overriding pkg-config. :::

::: option LIBREADLINE_CFLAGS :::

::: option LIBREADLINE_LIBS

C compiler and linker flags for libreadline, used by readline{.interpreted-text role="mod"} module, overriding pkg-config. :::

::: option LIBSQLITE3_CFLAGS :::

::: option LIBSQLITE3_LIBS

C compiler and linker flags for libsqlite3, used by sqlite3{.interpreted-text role="mod"} module, overriding pkg-config. :::

::: option LIBUUID_CFLAGS :::

::: option LIBUUID_LIBS

C compiler and linker flags for libuuid, used by uuid{.interpreted-text role="mod"} module, overriding pkg-config. :::

::: option LIBZSTD_CFLAGS :::

:::: option LIBZSTD_LIBS

C compiler and linker flags for libzstd, used by compression.zstd{.interpreted-text role="mod"} module, overriding pkg-config.

::: versionadded 3.14 ::: ::::

::: option PANEL_CFLAGS :::

::: option 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{.interpreted-text role="mod"} module, overriding pkg-config. :::

::: option TCLTK_CFLAGS :::

::: option TCLTK_LIBS

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

::: option ZLIB_CFLAGS :::

::: option ZLIB_LIBS

C compiler and linker flags for libzlib, used by gzip{.interpreted-text role="mod"} module, overriding pkg-config. :::

WebAssembly Options

:::: option

--enable-wasm-dynamic-linking

:

Turn on dynamic linking support for WASM.

Dynamic linking enables dlopen. File size of the executable increases due to limited dead code elimination and additional features.

::: versionadded 3.11 ::: ::::

:::: option

--enable-wasm-pthreads

:

Turn on pthreads support for WASM.

::: versionadded 3.11 ::: ::::

Install Options

::: option

--prefix=PREFIX

:

Install architecture-independent files in PREFIX. On Unix, it defaults to /usr/local{.interpreted-text role="file"}.

This value can be retrieved at runtime using sys.prefix{.interpreted-text role="data"}.

As an example, one can use --prefix="$HOME/.local/" to install a Python in its home directory. :::

::: option

--exec-prefix=EPREFIX

:

Install architecture-dependent files in EPREFIX, defaults to --prefix{.interpreted-text role="option"}.

This value can be retrieved at runtime using sys.exec_prefix{.interpreted-text role="data"}. :::

:::: option

--disable-test-modules

:

Don't build nor install test modules, like the test{.interpreted-text role="mod"} package or the !_testcapi{.interpreted-text role="mod"} extension module (built and installed by default).

::: versionadded 3.10 ::: ::::

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

Select the ensurepip{.interpreted-text role="mod"} command run on Python installation:

• upgrade (default): run python -m ensurepip --altinstall --upgrade command.
• install: run python -m ensurepip --altinstall command;
• no: don't run ensurepip;

::: versionadded 3.6 ::: ::::

Performance options

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.

::::::: option

--enable-optimizations

:

Enable Profile Guided Optimization (PGO) using PROFILE_TASK{.interpreted-text role="envvar"} (disabled by default).

The C compiler Clang requires llvm-profdata program for PGO. On macOS, GCC also requires it: GCC is just an alias to Clang on macOS.

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

:::: note ::: title Note :::

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{.interpreted-text role="envvar"}. ::::

::: versionadded 3.6 :::

::: versionchanged 3.10 Use -fno-semantic-interposition on GCC. ::: :::::::

::::: envvar PROFILE_TASK

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

Default: -m test --pgo --timeout=$(TESTTIMEOUT).

::: versionadded 3.8 :::

::: versionchanged 3.13 Task failure is no longer ignored silently. ::: :::::

:::::: option --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).

::: versionadded 3.6 :::

::: versionadded 3.11 To use ThinLTO feature, use --with-lto=thin on Clang. :::

::: versionchanged 3.12 Use ThinLTO as the default optimization policy on Clang if the compiler accepts the flag. ::: ::::::

:::: option

--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{.interpreted-text role="envvar"} and !BOLT_APPLY_FLAGS{.interpreted-text role="envvar"} configure{.interpreted-text role="program"} variables can be defined to override the default set of arguments for llvm-bolt{.interpreted-text role="program"} to instrument and apply BOLT data to binaries, respectively.

::: versionadded 3.12 ::: ::::

:::: option BOLT_APPLY_FLAGS

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

::: versionadded 3.12 ::: ::::

:::: option BOLT_INSTRUMENT_FLAGS

Arguments to llvm-bolt when instrumenting binaries.

::: versionadded 3.12 ::: ::::

::: option

--with-computed-gotos

:

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

:::: option

--with-tail-call-interp

:

Enable interpreters using tail calls in CPython. If enabled, enabling PGO (--enable-optimizations{.interpreted-text role="option"}) is highly recommended. This option specifically requires a C compiler with proper tail call support, and the preserve_none calling convention. For example, Clang 19 and newer supports this feature.

::: versionadded 3.14 ::: ::::

::: option

--without-mimalloc

:

Disable the fast mimalloc <mimalloc>{.interpreted-text role="ref"} allocator (enabled by default).

See also PYTHONMALLOC{.interpreted-text role="envvar"} environment variable. :::

::: option

--without-pymalloc

:

Disable the specialized Python memory allocator pymalloc <pymalloc>{.interpreted-text role="ref"} (enabled by default).

See also PYTHONMALLOC{.interpreted-text role="envvar"} environment variable. :::

:::: option

--with-pymalloc-hugepages

:

Enable huge page support for pymalloc <pymalloc>{.interpreted-text role="ref"} arenas (disabled by default). When enabled, the arena size on 64-bit platforms is increased to 2 MiB and arena allocation uses MAP_HUGETLB (Linux) or MEM_LARGE_PAGES (Windows) with automatic fallback to regular pages.

Even when compiled with this option, huge pages are not used at runtime unless the PYTHON_PYMALLOC_HUGEPAGES{.interpreted-text role="envvar"} environment variable is set to 1. This opt-in is required because huge pages carry risks on Linux: if the huge-page pool is exhausted, page faults (including copy-on-write faults after os.fork{.interpreted-text role="func"}) deliver SIGBUS and kill the process.

The configure script checks that the platform supports MAP_HUGETLB and emits a warning if it is not available.

On Windows, use the --pymalloc-hugepages flag with build.bat or set the UsePymallocHugepages MSBuild property.

::: versionadded 3.15 ::: ::::

::: option

--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. :::

::: option

--enable-profiling

:

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

::: option

--with-strict-overflow

:

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

:::: option

--without-remote-debug

:

Deactivate remote debugging support described in 768{.interpreted-text role="pep"} (enabled by default). When this flag is provided the code that allows the interpreter to schedule the execution of a Python file in a separate process as described in 768{.interpreted-text role="pep"} is not compiled. This includes both the functionality to schedule code to be executed and the functionality to receive code to be executed.

This macro is defined by default, unless Python is configured with --without-remote-debug{.interpreted-text role="option"}.

Note that even if the macro is defined, remote debugging may not be available (for example, on an incompatible platform).

::: versionadded 3.14 ::: ::::

Python Debug Build {#debug-build}

A debug build is Python built with the --with-pydebug{.interpreted-text role="option"} configure option.

Effects of a debug build:

• Display all warnings by default: the list of default warning filters is empty in the warnings{.interpreted-text role="mod"} module.
• Add d to sys.abiflags{.interpreted-text role="data"}.
• Add !sys.gettotalrefcount{.interpreted-text role="func"} function.
• Add -X showrefcount <-X>{.interpreted-text role="option"} command line option.
• Add -d{.interpreted-text role="option"} command line option and PYTHONDEBUG{.interpreted-text role="envvar"} 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 <default-memory-allocators>{.interpreted-text role="ref"} 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{.interpreted-text role="option"} 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{.interpreted-text role="func"} function) runs some basic checks on objects consistency.
  • The !Py_SAFE_DOWNCAST(){.interpreted-text role="c:macro"} macro checks for integer underflow and overflow when downcasting from wide types to narrow types.

See also the Python Development Mode <devmode>{.interpreted-text role="ref"} and the --with-trace-refs{.interpreted-text role="option"} configure option.

::: versionchanged 3.8 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{.interpreted-text role="option"} option). :::

Debug options

::: option

--with-pydebug

:

Build Python in debug mode <debug-build>{.interpreted-text role="ref"}: define the Py_DEBUG macro (disabled by default). :::

::::: option

--with-trace-refs

:

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

Effects:

• Define the Py_TRACE_REFS macro.
• Add sys.getobjects{.interpreted-text role="func"} function.
• Add PYTHONDUMPREFS{.interpreted-text role="envvar"} environment variable.

The PYTHONDUMPREFS{.interpreted-text role="envvar"} environment variable can be used to dump objects and reference counts still alive at Python exit.

Statically allocated objects <static-types>{.interpreted-text role="ref"} are not traced.

::: versionadded 3.8 :::

::: versionchanged 3.13 This build is now ABI compatible with release build and debug build <debug-build>{.interpreted-text role="ref"}. ::: :::::

:::: option

--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{.interpreted-text role="envvar"} compiler variable.

See also the --with-pydebug{.interpreted-text role="option"} option (debug build <debug-build>{.interpreted-text role="ref"}) which also enables assertions.

::: versionadded 3.6 ::: ::::

::: option

--with-valgrind

:

Enable Valgrind support (default is no). :::

:::: option

--with-dtrace

:

Enable DTrace support (default is no).

See Instrumenting CPython with DTrace and SystemTap <instrumentation>{.interpreted-text role="ref"}.

::: versionadded 3.6 ::: ::::

:::: option

--with-address-sanitizer

:

Enable AddressSanitizer memory error detector, asan (default is no). To improve ASan detection capabilities you may also want to combine this with --without-pymalloc{.interpreted-text role="option"} to disable the specialized small-object allocator whose allocations are not tracked by ASan.

::: versionadded 3.6 ::: ::::

:::: option

--with-memory-sanitizer

:

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

::: versionadded 3.6 ::: ::::

:::: option

--with-undefined-behavior-sanitizer

:

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

::: versionadded 3.6 ::: ::::

:::: option

--with-thread-sanitizer

:

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

::: versionadded 3.13 ::: ::::

Linker options

::: option

--enable-shared

:

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

:::: option

--without-static-libpython

:

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

::: versionadded 3.10 ::: ::::

Libraries options

::: option --with-libs='lib1 ...'

Link against additional libraries (default is no). :::

::: option

--with-system-expat

:

Build the !pyexpat{.interpreted-text role="mod"} module using an installed expat library (default is no). :::

:::::::: option

--with-system-libmpdec

:

Build the _decimal extension module using an installed mpdecimal library, see the decimal{.interpreted-text role="mod"} module (default is yes).

::: versionadded 3.3 :::

::: versionchanged 3.13 Default to using the installed mpdecimal library. :::

::: versionchanged 3.15

A bundled copy of the library will no longer be selected implicitly if an installed mpdecimal library is not found. In Python 3.15 only, it can still be selected explicitly using --with-system-libmpdec=no or --without-system-libmpdec. :::

::: deprecated-removed 3.13 3.16 A copy of the mpdecimal library sources will no longer be distributed with Python 3.16. :::

::: seealso LIBMPDEC_CFLAGS{.interpreted-text role="option"} and LIBMPDEC_LIBS{.interpreted-text role="option"}. ::: ::::::::

:::: option --with-readline=readline|editline

Designate a backend library for the readline{.interpreted-text role="mod"} module.

• readline: Use readline as the backend.
• editline: Use editline as the backend.

::: versionadded 3.10 ::: ::::

:::: option

--without-readline

:

Don't build the readline{.interpreted-text role="mod"} module (built by default).

Don't define the HAVE_LIBREADLINE macro.

::: versionadded 3.10 ::: ::::

::: option

--with-libm=STRING

:

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

::: option

--with-libc=STRING

:

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

:::: option

--with-openssl=DIR

:

Root of the OpenSSL directory.

::: versionadded 3.7 ::: ::::

:::: option --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{.interpreted-text role="option"} and pkg-config;
• DIR: set an explicit rpath.

::: versionadded 3.10 ::: ::::

Security Options

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

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

• siphash13 (default);
• siphash24;
• fnv.

::: versionadded 3.4 :::

::: versionadded 3.11 siphash13 is added and it is the new default. ::: :::::

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

Built-in hash modules:

• md5;
• sha1;
• sha256;
• sha512;
• sha3 (with shake);
• blake2.

::: versionadded 3.9 ::: ::::

::::: option --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{.interpreted-text role="mod"} module.

::: versionadded 3.7 :::

::: versionchanged 3.10

The settings python and STRING also set TLS 1.2 as minimum protocol version. ::: :::::

:::: option

--disable-safety

:

Disable compiler options that are recommended by OpenSSF for security reasons with no performance overhead. If this option is not enabled, CPython will be built based on safety compiler options with no slow down. When this option is enabled, CPython will not be built with the compiler options listed below.

The following compiler options are disabled with !--disable-safety{.interpreted-text role="option"}:

• -fstack-protector-strong: Enable run-time checks for stack-based buffer overflows.
• -Wtrampolines: Enable warnings about trampolines that require executable stacks.

::: versionadded 3.14 ::: ::::

:::: option

--enable-slower-safety

:

Enable compiler options that are recommended by OpenSSF for security reasons which require overhead. If this option is not enabled, CPython will not be built based on safety compiler options which performance impact. When this option is enabled, CPython will be built with the compiler options listed below.

The following compiler options are enabled with !--enable-slower-safety{.interpreted-text role="option"}:

• -D_FORTIFY_SOURCE=3: Fortify sources with compile- and run-time checks for unsafe libc usage and buffer overflows.

::: versionadded 3.14 ::: ::::

macOS Options

See Mac/README.rst{.interpreted-text role="source"}.

::: option

--enable-universalsdk

:
:::

::: option

--enable-universalsdk=SDKDIR

:

Create a universal binary build. SDKDIR specifies which macOS SDK should be used to perform the build (default is no). :::

::: option

--enable-framework

:
:::

::: option

--enable-framework=INSTALLDIR

:

Create a Python.framework rather than a traditional Unix install. Optional INSTALLDIR specifies the installation path (default is no). :::

::: option

--with-universal-archs=ARCH

:

Specify the kind of universal binary that should be created. This option is only valid when --enable-universalsdk{.interpreted-text role="option"} is set.

Options:

• universal2 (x86-64 and arm64);
• 32-bit (PPC and i386);
• 64-bit (PPC64 and x86-64);
• 3-way (i386, PPC and x86-64);
• intel (i386 and x86-64);
• intel-32 (i386);
• intel-64 (x86-64);
• all (PPC, i386, PPC64 and x86-64).

Note that values for this configuration item are not the same as the identifiers used for universal binary wheels on macOS. See the Python Packaging User Guide for details on the packaging platform compatibility tags used on macOS :::

::: option

--with-framework-name=FRAMEWORK

:

Specify the name for the python framework on macOS only valid when --enable-framework{.interpreted-text role="option"} is set (default: Python). :::

::: option

--with-app-store-compliance

:
:::

:::: option

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

:

The Python standard library contains strings that are known to trigger automated inspection tool errors when submitted for distribution by the macOS and iOS App Stores. If enabled, this option will apply the list of patches that are known to correct app store compliance. A custom patch file can also be specified. This option is disabled by default.

::: versionadded 3.13 ::: ::::

iOS Options

See iOS/README.rst{.interpreted-text role="source"}.

::: option

--enable-framework=INSTALLDIR

:

Create a Python.framework. Unlike macOS, the INSTALLDIR argument specifying the installation path is mandatory. :::

::: option

--with-framework-name=FRAMEWORK

:

Specify the name for the framework (default: Python). :::

Cross Compiling Options

Cross compiling, also known as cross building, can be used to build Python for another CPU architecture or platform. Cross compiling requires a Python interpreter for the build platform. The version of the build Python must match the version of the cross compiled host Python.

::: option

--build=BUILD

:

configure for building on BUILD, usually guessed by config.guess{.interpreted-text role="program"}. :::

::: option

--host=HOST

:

cross-compile to build programs to run on HOST (target platform) :::

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

path to build python binary for cross compiling

::: versionadded 3.11 ::: ::::

::: option CONFIG_SITE=file

An environment variable that points to a file with configure overrides.

Example config.site file:

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

:::

:::: option HOSTRUNNER

Program to run CPython for the host platform for cross-compilation.

::: versionadded 3.11 ::: ::::

Cross compiling example:

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

Python Build System

Main files of the build system

• configure.ac{.interpreted-text role="file"} => configure{.interpreted-text role="file"};
• Makefile.pre.in{.interpreted-text role="file"} => Makefile{.interpreted-text role="file"} (created by configure{.interpreted-text role="file"});
• pyconfig.h{.interpreted-text role="file"} (created by configure{.interpreted-text role="file"});
• Modules/Setup{.interpreted-text role="file"}: C extensions built by the Makefile using Module/makesetup{.interpreted-text role="file"} shell script;

Main build steps

• 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{.interpreted-text role="file"}).

Main Makefile targets

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 (chosen if the host platform matches wasm32-wasi* or wasm32-emscripten)
• 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.

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.

make profile-opt

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

make clean

Remove built files.

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.[^6]

make install

Build the all target and install Python.

make test

Build the all target and run the Python test suite with the --fast-ci option without GUI tests. Variables:

• TESTOPTS: additional regrtest command-line options.
• TESTPYTHONOPTS: additional Python command-line options.
• TESTTIMEOUT: timeout in seconds (default: 10 minutes).

make ci

This is similar to make test, but uses the -ugui to also run GUI tests.

::: versionadded 3.14 :::

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.

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.

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{.interpreted-text role="file"} 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(){.interpreted-text role="c:macro"}, !PyAPI_DATA(){.interpreted-text role="c:macro"} and PyMODINIT_FUNC{.interpreted-text role="c:macro"} macros of Include/exports.h{.interpreted-text role="file"} 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}(){.interpreted-text role="samp"} function is not exported, causing an ImportError{.interpreted-text role="exc"} on import.

Compiler and linker flags

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

Preprocessor flags

:::: envvar CONFIGURE_CPPFLAGS

Value of CPPFLAGS{.interpreted-text role="envvar"} variable passed to the ./configure script.

::: versionadded 3.6 ::: ::::

::: envvar CPPFLAGS

(Objective) C/C++ preprocessor flags, e.g. -I{include_dir}{.interpreted-text role="samp"} if you have headers in a nonstandard directory include_dir.

Both CPPFLAGS{.interpreted-text role="envvar"} and LDFLAGS{.interpreted-text role="envvar"} need to contain the shell's value to be able to build extension modules using the directories specified in the environment variables. :::

:::: envvar BASECPPFLAGS

::: versionadded 3.4 ::: ::::

:::: envvar PY_CPPFLAGS

Extra preprocessor flags added for building the interpreter object files.

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

::: versionadded 3.2 ::: ::::

Compiler flags

::: envvar CC

C compiler command.

Example: gcc -pthread. :::

::: envvar CXX

C++ compiler command.

Example: g++ -pthread. :::

::: envvar CFLAGS

C compiler flags. :::

:::: envvar CFLAGS_NODIST

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

In particular, CFLAGS{.interpreted-text role="envvar"} 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{.interpreted-text role="envvar"} 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.

::: versionadded 3.5 ::: ::::

:::: envvar COMPILEALL_OPTS

Options passed to the compileall{.interpreted-text role="mod"} command line when building PYC files in make install. Default: -j0.

::: versionadded 3.12 ::: ::::

::: envvar EXTRA_CFLAGS

Extra C compiler flags. :::

:::: envvar CONFIGURE_CFLAGS

Value of CFLAGS{.interpreted-text role="envvar"} variable passed to the ./configure script.

::: versionadded 3.2 ::: ::::

:::: envvar CONFIGURE_CFLAGS_NODIST

Value of CFLAGS_NODIST{.interpreted-text role="envvar"} variable passed to the ./configure script.

::: versionadded 3.5 ::: ::::

::: envvar BASECFLAGS

Base compiler flags. :::

::: envvar OPT

Optimization flags. :::

:::: envvar CFLAGS_ALIASING

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

::: versionadded 3.7 ::: ::::

::: envvar CCSHARED

Compiler flags used to build a shared library.

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

::: envvar CFLAGSFORSHARED

Extra C flags added for building the interpreter object files.

Default: $(CCSHARED) when --enable-shared{.interpreted-text role="option"} is used, or an empty string otherwise. :::

::: envvar PY_CFLAGS

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

:::: envvar PY_CFLAGS_NODIST

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

::: versionadded 3.5 ::: ::::

:::: envvar PY_STDMODULE_CFLAGS

C flags used for building the interpreter object files.

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

::: versionadded 3.7 ::: ::::

:::: envvar PY_CORE_CFLAGS

Default: $(PY_STDMODULE_CFLAGS) -DPy_BUILD_CORE.

::: versionadded 3.2 ::: ::::

:::: envvar PY_BUILTIN_MODULE_CFLAGS

Compiler flags to build a standard library extension module as a built-in module, like the posix{.interpreted-text role="mod"} module.

Default: $(PY_STDMODULE_CFLAGS) -DPy_BUILD_CORE_BUILTIN.

::: versionadded 3.8 ::: ::::

::: envvar PURIFY

Purify command. Purify is a memory debugger program.

Default: empty string (not used). :::

Linker flags

::: envvar LINKCC

Linker command used to build programs like python and _testembed.

Default: $(PURIFY) $(CC). :::

:::: envvar CONFIGURE_LDFLAGS

Value of LDFLAGS{.interpreted-text role="envvar"} variable passed to the ./configure script.

Avoid assigning CFLAGS{.interpreted-text role="envvar"}, LDFLAGS{.interpreted-text role="envvar"}, etc. so users can use them on the command line to append to these values without stomping the pre-set values.

::: versionadded 3.2 ::: ::::

::: envvar LDFLAGS_NODIST

LDFLAGS_NODIST{.interpreted-text role="envvar"} is used in the same manner as CFLAGS_NODIST{.interpreted-text role="envvar"}. Use it when a linker flag should not be part of LDFLAGS{.interpreted-text role="envvar"} once Python is installed (65320{.interpreted-text role="gh"}).

In particular, LDFLAGS{.interpreted-text role="envvar"} 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{.interpreted-text role="envvar"} would take precedence over user- and package-supplied -L flags. :::

:::: envvar CONFIGURE_LDFLAGS_NODIST

Value of LDFLAGS_NODIST{.interpreted-text role="envvar"} variable passed to the ./configure script.

::: versionadded 3.8 ::: ::::

::: envvar LDFLAGS

Linker flags, e.g. -L{lib_dir}{.interpreted-text role="samp"} if you have libraries in a nonstandard directory lib_dir.

Both CPPFLAGS{.interpreted-text role="envvar"} and LDFLAGS{.interpreted-text role="envvar"} need to contain the shell's value to be able to build extension modules using the directories specified in the environment variables. :::

::: envvar LIBS

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

Example: -lrt. :::

::: envvar LDSHARED

Command to build a shared library.

Default: @LDSHARED@ $(PY_LDFLAGS). :::

::: envvar BLDSHARED

Command to build libpython shared library.

Default: @BLDSHARED@ $(PY_CORE_LDFLAGS). :::

::: envvar PY_LDFLAGS

Default: $(CONFIGURE_LDFLAGS) $(LDFLAGS). :::

:::: envvar PY_LDFLAGS_NODIST

Default: $(CONFIGURE_LDFLAGS_NODIST) $(LDFLAGS_NODIST).

::: versionadded 3.8 ::: ::::

:::: envvar PY_CORE_LDFLAGS

Linker flags used for building the interpreter object files.

::: versionadded 3.8 ::: ::::

Footnotes

[^1]: If libmpdec is not available, the decimal{.interpreted-text role="mod"} module will use a pure-Python implementation. See --with-system-libmpdec{.interpreted-text role="option"} for details.

[^2]: See --with-readline{.interpreted-text role="option"} for choosing the backend for the readline{.interpreted-text role="mod"} module.

[^3]: The uuid{.interpreted-text role="mod"} module uses _uuid to generate "safe" UUIDs. See the module documentation for details.

[^4]: The curses{.interpreted-text role="mod"} module requires the libncurses or libncursesw library. The curses.panel{.interpreted-text role="mod"} module additionally requires the libpanel or libpanelw library.

[^5]: If OpenSSL is not available, the hashlib{.interpreted-text role="mod"} module will use bundled implementations of several hash functions. See --with-builtin-hashlib-hashes{.interpreted-text role="option"} for forcing usage of OpenSSL.

[^6]: 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.