tentative fixup

Author: neutrinoceros

meson.build

@@ -1,26 +1,54 @@
-project('gpgi', 'c', 'cython', meson_version: '>=1.5.0')
+project('gpgi', 'cython', meson_version: '>=1.5.0')
 
 py = import('python').find_installation(pure: false)
 
 min_numpy_version = '1.25.0'  # keep in sync with pyproject.toml
 cy = meson.get_compiler('cython')
 cython = find_program(cy.cmd_array()[0])
 
+numpy_nodepr_api = ['-DNPY_NO_DEPRECATED_API=NPY_1_25_API_VERSION']
 
-# https://github.com/mesonbuild/meson/issues/9598
-incdir_numpy = run_command(py,
-  [
-    '-c',
-    'import os; os.chdir(".."); import numpy; print(numpy.get_include())'
-  ],
-  check: true
-).stdout().strip()
-
-inc_np = include_directories(incdir_numpy)
+# copied from PyWavelets
+# https://github.com/PyWavelets/pywt/blob/becef5486174c77727ea2a60e6392744b2cc1d4a/pywt/_extensions/meson.build#L13
+# Uses the `numpy-config` executable (or a user's numpy.pc pkg-config file),
+# will work for numpy>=2.0.0b1 and meson>=1.4.0
+_numpy_dep = dependency('numpy', required: false)
+if _numpy_dep.found()
+  np_dep = declare_dependency(dependencies: _numpy_dep, compile_args: numpy_nodepr_api)
+else
+  # For cross-compilation it is often not possible to run the Python interpreter
+  # in order to retrieve numpy's include directory. It can be specified in the
+  # cross file instead:
+  #   [properties]
+  #   numpy-include-dir = /abspath/to/host-pythons/site-packages/numpy/core/include
+  #
+  # This uses the path as is, and avoids running the interpreter.
+  incdir_numpy = meson.get_external_property('numpy-include-dir', 'not-given')
+  if incdir_numpy == 'not-given'
+    incdir_numpy = run_command(py,
+      [
+        '-c',
+        '''import os
+import numpy as np
+try:
+  incdir = os.path.relpath(np.get_include())
+except Exception:
+  incdir = np.get_include()
+print(incdir)
+    '''
+      ],
+      check: true
+    ).stdout().strip()
+  endif
+  inc_np = include_directories(incdir_numpy)
+  np_dep = declare_dependency(include_directories: inc_np, compile_args: numpy_nodepr_api)
+endif
 
 py.extension_module(
-    'gpgi._lib',
+    '_lib',
     'src/gpgi/_lib.pyx',
+    subdir: 'gpgi',
     install: true,
-    include_directories : [inc_np],
+    dependencies : [np_dep],
+    c_args: numpy_nodepr_api,
 )