Modernize build for Python 3.10+/3.12 and NumPy 2

.gitignore

@@ -20,6 +20,10 @@ __pycache__/
 
 # environment
 .pyenv
+.venv*/
+
+# Local wheel artifacts
+*.whl
 
 # Distribution / packaging
 .Python

README.md

@@ -38,7 +38,21 @@ pip install spams
 Make sure you have install libblas & liblapack (see above)
 ```bash
 git clone https://github.com/getspams/spams-python
-cd spams-python
+# spams-python
+
+## OpenBLAS / OpenMP warning
+If you see messages like:
+
+> OpenBLAS Warning : Detect OpenMP Loop and this application may hang. Please rebuild the library with USE_OPENMP=1 option
+
+This comes from **OpenBLAS**, typically when:
+- SPAMS was built with OpenMP enabled (for parallelism), and
+- the linked OpenBLAS was built **without** OpenMP support.
+
+Usually it is just a warning, but if you want to silence/avoid it you can:
+- Set `OPENBLAS_NUM_THREADS=1` (and/or `OMP_NUM_THREADS=1`) at runtime.
+- Install an OpenBLAS build compiled with OpenMP (`USE_OPENMP=1`) or use MKL.
+- Rebuild SPAMS without OpenMP by setting `SPAMS_DISABLE_OPENMP=1` (or `SPAMS_USE_OPENMP=0`) when installing.
 pip install -e .
 ```
 

pyproject.toml

@@ -1,5 +1,7 @@
 [build-system]
-requires = ["oldest-supported-numpy",
-            "setuptools<60.0",
-            "distro",
-            "wheel"]
+requires = [
+    "setuptools>=64",
+    "wheel",
+    "numpy>=2.0.0",
+]
+build-backend = "setuptools.build_meta"

setup.py

@@ -5,7 +5,7 @@
 from setuptools import setup, Extension
 from setuptools.command.build_ext import build_ext
 
-from distutils.sysconfig import get_python_inc
+import sysconfig
 # from distutils.util import get_platform
 
 def check_openmp():
@@ -43,93 +43,93 @@ def check_openmp():
     # output : 0 if ok, 1 if not
     return result
 
+def _split_env_paths(value: str):
+    if not value:
+        return []
+    return [p for p in value.split(os.pathsep) if p]
+
+
+def _split_env_args(value: str):
+    """Split a string of args like: "-Wl,--as-needed -lm"."""
+    if not value:
+        return []
+    return value.split()
+
+
+def _split_env_libs(value: str):
+    """Split a list of libraries from an env var.
+
+    Accepts comma and/or whitespace separated values.
+    """
+    if not value:
+        return []
+    # allow: "openblas" or "blas,lapack" or "blas lapack"
+    return [x for x in value.replace(',', ' ').split() if x]
+
+
+def _env_truthy(value: str) -> bool:
+    return value.strip().lower() not in {"0", "false", "no", "off", ""}
+
+
 def get_config():
     # Import numpy here, only when headers are needed
     import numpy as np
-    from numpy.distutils.system_info import blas_info
 
     incs = ['spams_wrap']
     for x in ['linalg', 'prox', 'decomp', 'dictLearn']:
         incs.append(os.path.join('spams_wrap', x))
+
+    # NumPy + Python headers
     incs.append(np.get_include())
-    incs.append(get_python_inc())
-    incs.extend(blas_info().get_include_dirs())
+    incs.append(sysconfig.get_path('include'))
+
+    # Optional user overrides
+    incs.extend(_split_env_paths(os.environ.get('SPAMS_INCLUDE_DIRS', '')))
 
     cc_flags = ['-fPIC', '-Wunused-variable', '-Wno-uninitialized']
     if sys.maxsize > 2**32:
         cc_flags.append('-m64')
     else:
         cc_flags.append('-m32')
 
-    # blas/lapack compile/linking info
-    try:
-        blas_opt_info = np.__config__.blas_opt_info
-    except:
-        try:
-            blas_opt_info = np.__config__.blas_ilp64_opt_info
-        except:
-            blas_opt_info = None
-
-    try:
-        lapack_opt_info = np.__config__.lapack_opt_info
-    except:
-        try:
-            lapack_opt_info = np.__config__.lapack_ilp64_opt_info
-        except:
-            lapack_opt_info = None
-
-    # blas extra compile args
-    if blas_opt_info is not None:
-        for _ in blas_opt_info.get('extra_compile_args', []):
-            if _ not in cc_flags:
-                cc_flags.append(_)
-
-    # lapack extra compile args
-    if lapack_opt_info is not None:
-        for _ in lapack_opt_info.get('extra_compile_args', []):
-            if _ not in cc_flags:
-                cc_flags.append(_)
-
     # linking flags
     link_flags = []
 
-    # blas extra linking flags
-    if blas_opt_info is not None:
-        for _ in blas_opt_info.get('extra_link_args', []):
-            if _ not in link_flags:
-                link_flags.append(_)
-
-    # lapack extra linking flags
-    if lapack_opt_info is not None:
-        for _ in lapack_opt_info.get('extra_link_args', []):
-            if _ not in link_flags:
-                link_flags.append(_)
-
-    # libs
-    libs = ['stdc++']
-
-    # mkl ?
-    is_mkl = False
-    if blas_opt_info is not None:
-        for lib in blas_opt_info.get('libraries', []):
-            if 'mkl' in lib:
-                is_mkl = True
-                break
-
-    libdirs = blas_info().get_lib_dirs()
-    if is_mkl:
-        for _ in blas_opt_info.get('include_dirs', []):
-            if _ not in incs:
-                incs.append(_)
-        for _ in blas_opt_info.get('library_dirs', []):
-            if _ not in libdirs:
-                libdirs.append(_)
-        libs.extend(['mkl_rt'])
-    else:
-        libs.extend(['blas', 'lapack'])
+    # BLAS/LAPACK
+    libs = []
+    libdirs = _split_env_paths(os.environ.get('SPAMS_LIBRARY_DIRS', ''))
 
-    # openMP
-    if check_openmp() == 0:
+    env_libs = os.environ.get('SPAMS_BLAS_LIBS', '')
+    if env_libs:
+        libs.extend(_split_env_libs(env_libs))
+    else:
+        if sys.platform == 'darwin':
+            # Apple Accelerate provides BLAS+LAPACK
+            link_flags.extend(['-framework', 'Accelerate'])
+        else:
+            libs.extend(['blas', 'lapack'])
+
+    # Extra flags (escape hatch)
+    cc_flags.extend(_split_env_args(os.environ.get('SPAMS_EXTRA_COMPILE_ARGS', '')))
+    link_flags.extend(_split_env_args(os.environ.get('SPAMS_EXTRA_LINK_ARGS', '')))
+
+    # OpenMP
+    #
+    # Some OpenBLAS builds (USE_OPENMP=0) emit a runtime warning when called from
+    # OpenMP regions. We keep OpenMP enabled by default for performance, but
+    # provide a build-time escape hatch:
+    #   - SPAMS_DISABLE_OPENMP=1  (force off)
+    #   - SPAMS_USE_OPENMP=0/1    (explicit on/off)
+    disable_openmp = os.environ.get('SPAMS_DISABLE_OPENMP', '')
+    use_openmp = os.environ.get('SPAMS_USE_OPENMP', '')
+
+    enable_openmp = True
+    if disable_openmp:
+        enable_openmp = False
+    elif use_openmp:
+        enable_openmp = _env_truthy(use_openmp)
+
+    if enable_openmp and check_openmp() == 0:
         cc_flags.append('-fopenmp')
         link_flags.append('-fopenmp')
 
@@ -157,13 +157,22 @@ def run(self):
 
 def get_extension():
     # Generic initialization of the extension
-    spams_wrap = Extension('_spams_wrap',
-                           sources=['spams_wrap/spams_wrap.cpp'],
-                           extra_compile_args=['-DNDEBUG',
-                                               '-DUSE_BLAS_LIB',
-                                               '-std=c++11'],
-                           language='c++',
-                           depends=['spams_wrap/spams.h'])
+    spams_wrap = Extension(
+        'spams_wrap._spams_wrap',
+        sources=['spams_wrap/spams_wrap.cpp'],
+        define_macros=[
+            # Build against NumPy 2.x but target the 1.19 C-API feature set.
+            # (NumPy 2 defaults to this, but we keep it explicit.)
+            ('NPY_TARGET_VERSION', 'NPY_1_19_API_VERSION'),
+        ],
+        extra_compile_args=[
+            '-DNDEBUG',
+            '-DUSE_BLAS_LIB',
+            '-std=c++11',
+        ],
+        language='c++',
+        depends=['spams_wrap/spams.h'],
+    )
 
     return [spams_wrap]
 
@@ -194,8 +203,8 @@ def get_extension():
         "Source": "https://github.com/getspams/spams-python",
     },
     license='GPLv3',
-    python_requires='>=3',
-    install_requires=['numpy>=1.12', 'Pillow>=6.0', 'scipy>=1.0'],
+    python_requires='>=3.10',
+    install_requires=['numpy>=1.19', 'Pillow>=6.0', 'scipy>=1.0'],
     packages=['spams_wrap', 'spams', 'spams.tests'],
     cmdclass={'build_ext': CustomBuildExtCommand},
     ext_modules=get_extension(),

spams/__init__.py

@@ -1,6 +1,13 @@
 __all__ = ['spams']
 
-from pkg_resources import get_distribution
-__version__ = get_distribution('spams').version
+try:
+    from importlib.metadata import PackageNotFoundError, version
+except ImportError:  # pragma: no cover
+    from importlib_metadata import PackageNotFoundError, version
+
+try:
+    __version__ = version('spams')
+except PackageNotFoundError:  # pragma: no cover
+    __version__ = '0+unknown'
 
 from .spams import *

spams_wrap/__init__.py

@@ -1,6 +1,13 @@
-__all__ = ['spams_wrap', 'decomp','dictLearn','linalg','prox']
+__all__ = ['spams_wrap', 'decomp', 'dictLearn', 'linalg', 'prox']
 
-from pkg_resources import get_distribution
-__version__ = get_distribution('spams').version
+try:
+    from importlib.metadata import PackageNotFoundError, version
+except ImportError:  # pragma: no cover
+    from importlib_metadata import PackageNotFoundError, version
+
+try:
+    __version__ = version('spams')
+except PackageNotFoundError:  # pragma: no cover
+    __version__ = '0+unknown'
 
 from .spams_wrap import *