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build: refactor for simplicity

This commit is contained in:
David Hewitt 2021-04-24 10:52:58 +01:00
parent 28ccef2c72
commit fe9ed5c1fd
1 changed files with 200 additions and 230 deletions
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430
build.rs
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@ -3,18 +3,17 @@ use std::{
convert::AsRef,
env,
ffi::OsString,
fmt::Display,
fs::{self, DirEntry},
io,
path::{Path, PathBuf},
process::{Command, Stdio},
str::FromStr,
};
/// Minimum required Python version.
const PY3_MIN_MINOR: u8 = 6;
/// Minimum Python version PyO3 supports.
const MINIMUM_SUPPORTED_VERSION: PythonVersion = PythonVersion { major: 3, minor: 6 };
/// Maximum Python version that can be used as minimum required Python version with abi3.
const ABI3_MAX_MINOR: u8 = 9;
const CFG_KEY: &str = "py_sys_config";
type Result<T> = std::result::Result<T, Box<dyn std::error::Error>>;
@ -50,27 +49,31 @@ fn env_var(var: &str) -> Option<OsString> {
env::var_os(var)
}
/// Information returned from python interpreter
/// Configuration needed by PyO3 to build for the correct Python implementation.
///
/// Usually this is queried directly from the Python interpreter. When the `PYO3_NO_PYTHON` variable
/// is set, or during cross compile situations, then alternative strategies are used to populate
/// this type.
#[derive(Debug)]
struct InterpreterConfig {
version: PythonVersion,
libdir: Option<String>,
shared: bool,
ld_version: String,
/// Prefix used for determining the directory of libpython
base_prefix: String,
executable: PathBuf,
ld_version: Option<String>,
base_prefix: Option<String>,
executable: Option<String>,
calcsize_pointer: Option<u32>,
implementation: PythonInterpreterKind,
implementation: PythonImplementation,
build_flags: BuildFlags,
}
impl InterpreterConfig {
fn is_pypy(&self) -> bool {
self.implementation == PythonInterpreterKind::PyPy
self.implementation == PythonImplementation::PyPy
}
}
#[derive(Debug, Clone, PartialEq, PartialOrd)]
#[derive(Debug, Copy, Clone, PartialEq, Eq, PartialOrd, Ord)]
struct PythonVersion {
major: u8,
minor: u8,
@ -80,18 +83,24 @@ impl PythonVersion {
const PY37: Self = PythonVersion { major: 3, minor: 7 };
}
#[derive(Debug, Clone, PartialEq)]
pub enum PythonInterpreterKind {
impl Display for PythonVersion {
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
write!(f, "{}.{}", self.major, self.minor)
}
}
#[derive(Debug, Copy, Clone, PartialEq)]
pub enum PythonImplementation {
CPython,
PyPy,
}
impl FromStr for PythonInterpreterKind {
impl FromStr for PythonImplementation {
type Err = Box<dyn std::error::Error>;
fn from_str(s: &str) -> Result<Self> {
match s {
"CPython" => Ok(PythonInterpreterKind::CPython),
"PyPy" => Ok(PythonInterpreterKind::PyPy),
"CPython" => Ok(PythonImplementation::CPython),
"PyPy" => Ok(PythonImplementation::PyPy),
_ => bail!("Invalid interpreter: {}", s),
}
}
@ -198,21 +207,20 @@ fn cross_compiling() -> Result<Option<CrossCompileConfig>> {
}
/// A list of python interpreter compile-time preprocessor defines that
/// we will pick up and pass to rustc via --cfg=py_sys_config={varname};
/// we will pick up and pass to rustc via `--cfg=py_sys_config={varname}`;
/// this allows using them conditional cfg attributes in the .rs files, so
///
/// #[cfg(py_sys_config="{varname}"]
/// #[cfg(py_sys_config="{varname}"]
///
/// is the equivalent of #ifdef {varname} name in C.
/// is the equivalent of `#ifdef {varname}` in C.
///
/// see Misc/SpecialBuilds.txt in the python source for what these mean.
///
/// (hrm, this is sort of re-implementing what distutils does, except
/// by passing command line args instead of referring to a python.h)
#[derive(Debug)]
struct BuildFlags(HashSet<&'static str>);
impl BuildFlags {
const ALL: [&'static str; 5] = [
// TODO: Remove WITH_THREAD once Python 3.6 support dropped (as it's always on).
"WITH_THREAD",
"Py_DEBUG",
"Py_REF_DEBUG",
@ -233,27 +241,25 @@ impl BuildFlags {
/// Examine python's compile flags to pass to cfg by launching
/// the interpreter and printing variables of interest from
/// sysconfig.get_config_vars.
fn from_interpreter(python_path: &Path) -> Result<Self> {
fn from_interpreter(interpreter: &Path) -> Result<Self> {
if cargo_env_var("CARGO_CFG_TARGET_OS").unwrap() == "windows" {
return Ok(Self::windows_hardcoded());
}
let mut script = "import sysconfig; \
config = sysconfig.get_config_vars();"
.to_owned();
let mut script = String::from("import sysconfig\n");
script.push_str("config = sysconfig.get_config_vars()\n");
for k in BuildFlags::ALL.iter() {
script.push_str(&format!("print(config.get('{}', '0'));", k));
script.push_str(&format!("print(config.get('{}', '0'))\n", k));
}
let stdout = run_python_script(python_path, &script)?;
let stdout = run_python_script(&interpreter, &script)?;
let split_stdout: Vec<&str> = stdout.trim_end().lines().collect();
if split_stdout.len() != BuildFlags::ALL.len() {
bail!(
"Python stdout len didn't return expected number of lines: {}",
split_stdout.len()
);
}
ensure!(
split_stdout.len() == BuildFlags::ALL.len(),
"Python stdout len didn't return expected number of lines: {}",
split_stdout.len()
);
let flags = BuildFlags::ALL
.iter()
.zip(split_stdout)
@ -267,41 +273,40 @@ impl BuildFlags {
fn windows_hardcoded() -> Self {
// sysconfig is missing all the flags on windows, so we can't actually
// query the interpreter directly for its build flags.
//
// For the time being, this is the flags as defined in the python source's
// PC\pyconfig.h. This won't work correctly if someone has built their
// python with a modified pyconfig.h - sorry if that is you, you will have
// to comment/uncomment the lines below.
let mut flags = HashSet::new();
flags.insert("WITH_THREAD");
// This is defined #ifdef _DEBUG. The visual studio build seems to produce
// a specially named pythonXX_d.exe and pythonXX_d.dll when you build the
// Debug configuration, which this script doesn't currently support anyway.
// map.insert("Py_DEBUG", "1");
// Uncomment these manually if your python was built with these and you want
// the cfg flags to be set in rust.
//
// map.insert("Py_DEBUG", "1");
// map.insert("Py_REF_DEBUG", "1");
// map.insert("Py_TRACE_REFS", "1");
// map.insert("COUNT_ALLOCS", 1");
Self(flags)
}
fn fixup(&mut self, interpreter_config: &InterpreterConfig) {
fn abi3() -> Self {
let mut flags = HashSet::new();
flags.insert("WITH_THREAD");
Self(flags)
}
fn fixup(mut self, version: PythonVersion, implementation: PythonImplementation) -> Self {
if self.0.contains("Py_DEBUG") {
self.0.insert("Py_REF_DEBUG");
if interpreter_config.version <= PythonVersion::PY37 {
if version <= PythonVersion::PY37 {
// Py_DEBUG only implies Py_TRACE_REFS until Python 3.7
self.0.insert("Py_TRACE_REFS");
}
}
// WITH_THREAD is always on for Python 3.7, and for PyPy.
if interpreter_config.is_pypy() || interpreter_config.version >= PythonVersion::PY37 {
if implementation == PythonImplementation::PyPy || version >= PythonVersion::PY37 {
self.0.insert("WITH_THREAD");
}
self
}
}
@ -462,7 +467,7 @@ fn search_lib_dir(path: impl AsRef<Path>, cross: &CrossCompileConfig) -> Vec<Pat
/// [1]: https://github.com/python/cpython/blob/3.8/Lib/sysconfig.py#L348
fn load_cross_compile_from_sysconfigdata(
cross_compile_config: CrossCompileConfig,
) -> Result<(InterpreterConfig, BuildFlags)> {
) -> Result<InterpreterConfig> {
let sysconfig_path = find_sysconfigdata(&cross_compile_config)?;
let sysconfig_data = parse_sysconfigdata(sysconfig_path)?;
@ -474,27 +479,25 @@ fn load_cross_compile_from_sysconfigdata(
};
let calcsize_pointer = sysconfig_data.get_numeric("SIZEOF_VOID_P").ok();
let python_version = PythonVersion { major, minor };
let version = PythonVersion { major, minor };
let implementation = PythonImplementation::CPython;
let interpreter_config = InterpreterConfig {
version: python_version,
Ok(InterpreterConfig {
version,
libdir: cross_compile_config.lib_dir.to_str().map(String::from),
shared: sysconfig_data.get_bool("Py_ENABLE_SHARED")?,
ld_version,
base_prefix: "".to_string(),
executable: PathBuf::new(),
ld_version: Some(ld_version),
base_prefix: None,
executable: None,
calcsize_pointer,
implementation: PythonInterpreterKind::CPython,
};
let build_flags = BuildFlags::from_config_map(&sysconfig_data);
Ok((interpreter_config, build_flags))
implementation,
build_flags: BuildFlags::from_config_map(&sysconfig_data).fixup(version, implementation),
})
}
fn windows_hardcoded_cross_compile(
cross_compile_config: CrossCompileConfig,
) -> Result<(InterpreterConfig, BuildFlags)> {
) -> Result<InterpreterConfig> {
let (major, minor) = if let Some(version) = cross_compile_config.version {
let mut parts = version.split('.');
match (
@ -514,25 +517,20 @@ fn windows_hardcoded_cross_compile(
bail!("PYO3_CROSS_PYTHON_VERSION or an abi3-py3* feature must be specified when cross-compiling for Windows.")
};
let python_version = PythonVersion { major, minor };
let interpreter_config = InterpreterConfig {
version: python_version,
Ok(InterpreterConfig {
version: PythonVersion { major, minor },
libdir: cross_compile_config.lib_dir.to_str().map(String::from),
shared: true,
ld_version: format!("{}.{}", major, minor),
base_prefix: "".to_string(),
executable: PathBuf::new(),
ld_version: None,
base_prefix: None,
executable: None,
calcsize_pointer: None,
implementation: PythonInterpreterKind::CPython,
};
Ok((interpreter_config, BuildFlags::windows_hardcoded()))
implementation: PythonImplementation::CPython,
build_flags: BuildFlags::windows_hardcoded(),
})
}
fn load_cross_compile_info(
cross_compile_config: CrossCompileConfig,
) -> Result<(InterpreterConfig, BuildFlags)> {
fn load_cross_compile_info(cross_compile_config: CrossCompileConfig) -> Result<InterpreterConfig> {
match cargo_env_var("CARGO_CFG_TARGET_FAMILY") {
// Configure for unix platforms using the sysconfigdata file
Some(os) if os == "unix" => load_cross_compile_from_sysconfigdata(cross_compile_config),
@ -567,27 +565,17 @@ fn run_python_script(interpreter: &Path, script: &str) -> Result<String> {
});
match out {
Err(err) => {
if err.kind() == io::ErrorKind::NotFound {
bail!(
"Could not find any interpreter at {}, \
are you sure you have Python installed on your PATH?",
interpreter.display()
);
} else {
bail!(
"Failed to run the Python interpreter at {}: {}",
interpreter.display(),
err
);
}
}
Err(err) => bail!(
"failed to run the Python interpreter at {}: {}",
interpreter.display(),
err
),
Ok(ok) if !ok.status.success() => bail!("Python script failed"),
Ok(ok) => Ok(String::from_utf8(ok.stdout)?),
}
}
fn get_rustc_link_lib(config: &InterpreterConfig) -> String {
fn get_rustc_link_lib(config: &InterpreterConfig) -> Result<String> {
let link_name = if cargo_env_var("CARGO_CFG_TARGET_OS").unwrap() == "windows" {
if is_abi3() {
// Link against python3.lib for the stable ABI on Windows.
@ -609,16 +597,19 @@ fn get_rustc_link_lib(config: &InterpreterConfig) -> String {
}
} else {
match config.implementation {
PythonInterpreterKind::CPython => format!("python{}", config.ld_version),
PythonInterpreterKind::PyPy => format!("pypy{}-c", config.version.major),
PythonImplementation::CPython => match &config.ld_version {
Some(ld_version) => format!("python{}", ld_version),
None => bail!("failed to configure `ld_version` when compiling for unix"),
},
PythonImplementation::PyPy => format!("pypy{}-c", config.version.major),
}
};
format!(
Ok(format!(
"cargo:rustc-link-lib={link_model}{link_name}",
link_model = if config.shared { "" } else { "static=" },
link_name = link_name
)
))
}
fn get_venv_path() -> Option<PathBuf> {
@ -636,6 +627,11 @@ fn get_venv_path() -> Option<PathBuf> {
}
}
/// Attempts to locate a python interpreter. Locations are checked in the order listed:
/// 1. If `PYO3_PYTHON` is set, this intepreter is used.
/// 2. If in a virtualenv, that environment's interpreter is used.
/// 3. `python`, if this is functional a Python 3.x interpreter
/// 4. `python3`, as above
fn find_interpreter() -> Result<PathBuf> {
if let Some(exe) = env_var("PYO3_PYTHON") {
Ok(exe.into())
@ -657,37 +653,16 @@ fn find_interpreter() -> Result<PathBuf> {
}
})
.map(PathBuf::from)
.ok_or_else(|| "Python 3.x interpreter not found".into())
.ok_or_else(|| "no Python 3.x interpreter found".into())
}
}
/// Locate a suitable python interpreter and extract config from it.
///
/// The following locations are checked in the order listed:
///
/// 1. If `PYO3_PYTHON` is set, this intepreter is used and an error is raised if the
/// version doesn't match.
/// 2. `python`
/// 3. `python{major version}`
/// 4. `python{major version}.{minor version}`
///
/// If none of the above works, an error is returned
fn find_interpreter_and_get_config() -> Result<(InterpreterConfig, BuildFlags)> {
let python_interpreter = find_interpreter()?;
let interpreter_config = get_config_from_interpreter(&python_interpreter)?;
if interpreter_config.version.major == 3 {
return Ok((
interpreter_config,
BuildFlags::from_interpreter(&python_interpreter)?,
));
}
Err("No Python interpreter found".into())
}
/// Extract compilation vars from the specified interpreter.
fn get_config_from_interpreter(interpreter: &Path) -> Result<InterpreterConfig> {
let script = r#"
# Allow the script to run on Python 2, so that nicer error can be printed later.
from __future__ import print_function
import os.path
import platform
import struct
@ -696,20 +671,30 @@ from sysconfig import get_config_var
PYPY = platform.python_implementation() == "PyPy"
# Anaconda based python distributions have a static python executable, but include
# the shared library. Use the shared library for embedding to avoid rust trying to
# LTO the static library (and failing with newer gcc's, because it is old).
ANACONDA = os.path.exists(os.path.join(sys.base_prefix, "conda-meta"))
# sys.base_prefix is missing on Python versions older than 3.3; this allows the script to continue
# so that the version mismatch can be reported in a nicer way later.
base_prefix = getattr(sys, "base_prefix", None)
if base_prefix:
# Anaconda based python distributions have a static python executable, but include
# the shared library. Use the shared library for embedding to avoid rust trying to
# LTO the static library (and failing with newer gcc's, because it is old).
ANACONDA = os.path.exists(os.path.join(base_prefix, "conda-meta"))
else:
ANACONDA = False
def print_if_set(varname, value):
if value is not None:
print(varname, value)
libdir = get_config_var("LIBDIR")
print("version_major", sys.version_info[0])
print("version_minor", sys.version_info[1])
print("implementation", platform.python_implementation())
if libdir is not None:
print("libdir", libdir)
print("ld_version", get_config_var("LDVERSION") or get_config_var("py_version_short"))
print("base_prefix", sys.base_prefix)
print_if_set("libdir", libdir)
print_if_set("ld_version", get_config_var("LDVERSION"))
print_if_set("base_prefix", base_prefix)
print("framework", bool(get_config_var("PYTHONFRAMEWORK")))
print("shared", PYPY or ANACONDA or bool(get_config_var("Py_ENABLE_SHARED")))
print("executable", sys.executable)
@ -730,47 +715,52 @@ print("calcsize_pointer", struct.calcsize("P"))
_ => bail!("Unrecognised link model combination")
};
let version = PythonVersion {
major: map["version_major"].parse()?,
minor: map["version_minor"].parse()?,
};
let implementation = map["implementation"].parse()?;
Ok(InterpreterConfig {
version: PythonVersion {
major: map["version_major"].parse()?,
minor: map["version_minor"].parse()?,
},
implementation: map["implementation"].parse()?,
version,
implementation,
libdir: map.get("libdir").cloned(),
shared,
ld_version: map["ld_version"].clone(),
base_prefix: map["base_prefix"].clone(),
executable: map["executable"].clone().into(),
ld_version: map.get("ld_version").cloned(),
base_prefix: map.get("base_prefix").cloned(),
executable: map.get("executable").cloned(),
calcsize_pointer: Some(map["calcsize_pointer"].parse()?),
build_flags: BuildFlags::from_interpreter(interpreter)?.fixup(version, implementation),
})
}
fn configure(interpreter_config: &InterpreterConfig) -> Result<()> {
if interpreter_config.version.major == 2 {
// fail PYO3_PYTHON=python2 cargo ...
bail!("Python 2 is not supported");
}
fn ensure_python_version(interpreter_config: &InterpreterConfig) -> Result<()> {
ensure!(
interpreter_config.version >= MINIMUM_SUPPORTED_VERSION,
"the configured Python interpreter version ({}) is lower than PyO3's minimum supported version ({})",
interpreter_config.version,
MINIMUM_SUPPORTED_VERSION,
);
if interpreter_config.version.minor < PY3_MIN_MINOR {
bail!(
"Python 3 required version is 3.{}, current version is 3.{}",
PY3_MIN_MINOR,
interpreter_config.version.minor
);
}
check_target_architecture(interpreter_config)?;
Ok(())
}
fn emit_cargo_configuration(interpreter_config: &InterpreterConfig) -> Result<()> {
let target_os = cargo_env_var("CARGO_CFG_TARGET_OS").unwrap();
let is_extension_module = cargo_env_var("CARGO_FEATURE_EXTENSION_MODULE").is_some();
match (is_extension_module, target_os.as_str()) {
(_, "windows") => {
// always link on windows, even with extension module
println!("{}", get_rustc_link_lib(&interpreter_config));
println!(
"cargo:rustc-link-search=native={}\\libs",
interpreter_config.base_prefix
);
println!("{}", get_rustc_link_lib(&interpreter_config)?);
// Set during cross-compiling.
if let Some(libdir) = &interpreter_config.libdir {
println!("cargo:rustc-link-search=native={}", libdir);
}
// Set if we have an interpreter to use.
if let Some(base_prefix) = &interpreter_config.base_prefix {
println!("cargo:rustc-link-search=native={}\\libs", base_prefix);
}
}
(true, "macos") => {
// with extension module on macos some extra linker arguments are needed
@ -780,17 +770,19 @@ fn configure(interpreter_config: &InterpreterConfig) -> Result<()> {
(false, _) | (_, "android") => {
// other systems, only link libs if not extension module
// android always link.
println!("{}", get_rustc_link_lib(&interpreter_config));
println!("{}", get_rustc_link_lib(&interpreter_config)?);
if let Some(libdir) = &interpreter_config.libdir {
println!("cargo:rustc-link-search=native={}", libdir);
}
if interpreter_config.implementation == PythonInterpreterKind::PyPy {
// PyPy 3.7 changed LIBDIR to point to base_prefix/lib, so need to hard-code /bin
// search path too: https://foss.heptapod.net/pypy/pypy/-/issues/3442
println!(
"cargo:rustc-link-search=native={}/bin",
interpreter_config.base_prefix
);
if interpreter_config.implementation == PythonImplementation::PyPy {
// PyPy 7.3.4 changed LIBDIR to point to base_prefix/lib as a regression, so need
// to hard-code /bin search path too: https://foss.heptapod.net/pypy/pypy/-/issues/3442
//
// TODO: this workaround can probably be removed when PyPy 7.3.5 is released (and we
// can call it a PyPy bug).
if let Some(base_prefix) = &interpreter_config.base_prefix {
println!("cargo:rustc-link-search=native={}/bin", base_prefix);
}
}
}
_ => {}
@ -850,14 +842,18 @@ fn configure(interpreter_config: &InterpreterConfig) -> Result<()> {
interpreter_config.version.minor
};
for i in PY3_MIN_MINOR..=minor {
for i in MINIMUM_SUPPORTED_VERSION.minor..=minor {
println!("cargo:rustc-cfg=Py_3_{}", i);
}
for flag in &interpreter_config.build_flags.0 {
println!("cargo:rustc-cfg=py_sys_config=\"{}\"", flag)
}
Ok(())
}
fn check_target_architecture(interpreter_config: &InterpreterConfig) -> Result<()> {
fn ensure_target_architecture(interpreter_config: &InterpreterConfig) -> Result<()> {
// Try to check whether the target architecture matches the python library
let rust_target = match cargo_env_var("CARGO_CFG_TARGET_POINTER_WIDTH")
.unwrap()
@ -884,86 +880,60 @@ fn check_target_architecture(interpreter_config: &InterpreterConfig) -> Result<(
Some(n) => bail!("unexpected Python calcsize_pointer value: {}", n),
};
if rust_target != python_target {
bail!(
"Your Rust target architecture ({}) does not match your python interpreter ({})",
rust_target,
python_target
);
}
ensure!(
rust_target == python_target,
"Your Rust target architecture ({}) does not match your python interpreter ({})",
rust_target,
python_target
);
Ok(())
}
fn get_abi3_minor_version() -> Option<u8> {
(PY3_MIN_MINOR..=ABI3_MAX_MINOR)
(MINIMUM_SUPPORTED_VERSION.minor..=ABI3_MAX_MINOR)
.find(|i| cargo_env_var(&format!("CARGO_FEATURE_ABI3_PY3{}", i)).is_some())
}
fn configure_abi3_without_interpreter() {
println!("cargo:rustc-cfg=Py_LIMITED_API");
let mut flags = "FLAG_WITH_THREAD=1".to_string();
let abi_version = get_abi3_minor_version().unwrap_or(ABI3_MAX_MINOR);
for minor in PY3_MIN_MINOR..=abi_version {
println!("cargo:rustc-cfg=Py_3_{}", minor);
flags += &format!(",CFG_Py_3_{}", minor);
fn get_interpreter_config() -> Result<InterpreterConfig> {
// If PYO3_NO_PYTHON is set with abi3, we can build PyO3 without calling Python.
if let Some(abi3_version) = get_abi3_minor_version() {
if env_var("PYO3_NO_PYTHON").is_some() {
return Ok(InterpreterConfig {
version: PythonVersion {
major: 3,
minor: abi3_version,
},
implementation: PythonImplementation::CPython,
libdir: None,
build_flags: BuildFlags::abi3(),
base_prefix: None,
calcsize_pointer: None,
executable: None,
ld_version: None,
shared: true,
});
}
}
println!("cargo:rustc-cfg=py_sys_config=\"WITH_THREAD\"");
println!("cargo:python_flags={}", flags);
if cargo_env_var("CARGO_CFG_TARGET_FAMILY").unwrap() == "windows" {
// Unfortunately, on windows we can't build without at least providing
// python.lib to the linker. While maturin tells the linker the location
// of python.lib, we need to do the renaming here, otherwise cargo
// complains that the crate using pyo3 does not contains a `#[link(...)]`
// attribute with pythonXY.
println!("cargo:rustc-link-lib=pythonXY:python3");
if let Some(paths) = cross_compiling()? {
load_cross_compile_info(paths)
} else {
get_config_from_interpreter(&find_interpreter()?)
}
}
fn main_impl() -> Result<()> {
// If PYO3_NO_PYTHON is set with abi3, we can build PyO3 without calling Python.
// We only check for the abi3-py3{ABI3_MAX_MINOR} because lower versions depend on it.
if cargo_env_var("PYO3_NO_PYTHON").is_some()
&& cargo_env_var(&format!("CARGO_FEATURE_ABI3_PY3{}", ABI3_MAX_MINOR)).is_some()
{
println!("cargo:rerun-if-env-changed=PYO3_NO_PYTHON");
configure_abi3_without_interpreter();
return Ok(());
}
// 1. Setup cfg variables so we can do conditional compilation in this library based on the
// python interpeter's compilation flags. This is necessary for e.g. matching the right unicode
// and threading interfaces. First check if we're cross compiling, if so, we cannot run the
// target Python interpreter and have to parse pyconfig.h instead. If we're not cross
// compiling, locate the python interpreter based on the PATH, which should work smoothly with
// an activated virtualenv, and load from there.
//
// If you have troubles with your shell accepting '.' in a var name,
// try using 'env' (sorry but this isn't our fault - it just has to
// match the pkg-config package name, which is going to have a . in it).
//
// Detecting if cross-compiling by checking if the target triple is different from the host
// rustc's triple.
let (interpreter_config, mut build_flags) = if let Some(paths) = cross_compiling()? {
load_cross_compile_info(paths)?
} else {
find_interpreter_and_get_config()?
};
build_flags.fixup(&interpreter_config);
configure(&interpreter_config)?;
for flag in &build_flags.0 {
println!("cargo:rustc-cfg={}=\"{}\"", CFG_KEY, flag)
}
Ok(())
fn configure_pyo3() -> Result<()> {
let interpreter_config = get_interpreter_config()?;
ensure_python_version(&interpreter_config)?;
ensure_target_architecture(&interpreter_config)?;
emit_cargo_configuration(&interpreter_config)
}
fn main() {
// Print out error messages using display, to get nicer formatting.
let _ = main_impl().map_err(|e| {
eprintln!("Error: {}", e);
if let Err(e) = configure_pyo3() {
eprintln!("error: {}", e);
std::process::exit(1)
});
}
}