fix(macos): Added sysconfig-based Python link flags for sdist builds

Pass per-package LIBS/LDFLAGS env overrides into pip wheel so dbus-python can
link against the active CPython on macOS CI.

Author: jakub-kocka

_helper_functions.py

@@ -5,12 +5,15 @@
 #
 from __future__ import annotations
 
+import os
 import platform
 import re
 import sys
+import sysconfig
 
 from colorama import Fore
 from colorama import Style
+from packaging.requirements import InvalidRequirement
 from packaging.requirements import Requirement
 from packaging.utils import InvalidWheelFilename
 from packaging.utils import canonicalize_name
@@ -107,6 +110,52 @@ def get_no_binary_args(requirement_name: str) -> list:
     return []
 
 
+def get_pip_wheel_env_overrides(requirement_line: str) -> dict[str, str]:
+    """Per-package environment overrides for `pip wheel` builds.
+
+    Keep this narrowly scoped: used for CI-only build quirks where upstream sdists expect platform-specific
+    Python link flags.
+    """
+    try:
+        req = Requirement(str(requirement_line).strip())
+    except InvalidRequirement:
+        return {}
+
+    # dbus-python on macOS: its autoconf configure can fail to link a test program against CPython.
+    # Provide explicit LIBS/LDFLAGS derived from sysconfig so the build can locate the active Python library
+    # regardless of whether Python is a framework build or a shared library build.
+    if canonicalize_name(req.name) == canonicalize_name("dbus-python") and platform.system() == "Darwin":
+        libdir = sysconfig.get_config_var("LIBDIR") or ""
+        ldlibrary = sysconfig.get_config_var("LDLIBRARY") or ""  # e.g. libpython3.11.dylib
+
+        # Prefer an explicit absolute library path when available; it is the most robust across layouts.
+        libs_fragment = ""
+        if libdir and ldlibrary:
+            candidate = os.path.join(libdir, ldlibrary)
+            if os.path.exists(candidate):
+                libs_fragment = candidate
+
+        # Fallback to -L/-l if we can't find the actual library file.
+        if not libs_fragment:
+            maj, min = sys.version_info[:2]
+            libs_fragment = (f"-L{libdir} " if libdir else "") + f"-lpython{maj}.{min}"
+
+        # Append to any existing flags, don't overwrite.
+        existing_libs = os.environ.get("LIBS", "").strip()
+        existing_ldflags = os.environ.get("LDFLAGS", "").strip()
+
+        new_libs = (libs_fragment + (" " + existing_libs if existing_libs else "")).strip()
+        new_ldflags = existing_ldflags
+        if libdir:
+            rpath_flag = f"-Wl,-rpath,{libdir}"
+            if rpath_flag not in new_ldflags:
+                new_ldflags = (rpath_flag + (" " + new_ldflags if new_ldflags else "")).strip()
+
+        return {"LIBS": new_libs, "LDFLAGS": new_ldflags} if (new_libs or new_ldflags) else {}
+
+    return {}
+
+
 def _safe_text_for_stdout(text: str) -> str:
     """Avoid UnicodeEncodeError when printing pip/tool output on Windows (e.g. cp1252 console)."""
     encoding = getattr(sys.stdout, "encoding", None) or "utf-8"

build_wheels.py

@@ -27,6 +27,7 @@
 
 from _helper_functions import get_current_platform
 from _helper_functions import get_no_binary_args
+from _helper_functions import get_pip_wheel_env_overrides
 from _helper_functions import merge_requirements
 from _helper_functions import print_color
 from yaml_list_adapter import YAMLListAdapter
@@ -293,6 +294,9 @@ def build_wheels(requirements: set, local_links: bool = True) -> dict:
                 argument = match.group(1).strip()
                 arg_param = match.group(2).strip()
             if arg_param in requirement.name:
+                env_overrides = get_pip_wheel_env_overrides(str(requirement))
+                env = os.environ.copy()
+                env.update(env_overrides)
                 out = subprocess.run(
                     [
                         f"{sys.executable}",
@@ -311,6 +315,7 @@ def build_wheels(requirements: set, local_links: bool = True) -> dict:
                         f"{argument}",
                         f"{arg_param}",
                     ],
+                    env=env if env_overrides else None,
                     stdout=subprocess.PIPE,
                     stderr=subprocess.PIPE,
                 )
@@ -323,6 +328,9 @@ def build_wheels(requirements: set, local_links: bool = True) -> dict:
         # requirement wheel build
         # Get no-binary args for packages that should be built from source
         no_binary_args = get_no_binary_args(requirement.name)
+        env_overrides = get_pip_wheel_env_overrides(str(requirement))
+        env = os.environ.copy()
+        env.update(env_overrides)
 
         out = subprocess.run(
             [
@@ -341,6 +349,7 @@ def build_wheels(requirements: set, local_links: bool = True) -> dict:
                 "--no-build-isolation",
             ]
             + no_binary_args,
+            env=env if env_overrides else None,
             stdout=subprocess.PIPE,
             stderr=subprocess.PIPE,
         )

build_wheels_from_file.py

@@ -17,6 +17,7 @@
 from packaging.utils import canonicalize_name
 
 from _helper_functions import get_no_binary_args
+from _helper_functions import get_pip_wheel_env_overrides
 from _helper_functions import print_color
 
 # Do not pass --no-binary for these in --force-interpreter-binary mode:
@@ -124,6 +125,9 @@ def _apply_force_interpreter_binary(cli_flag: bool) -> bool:
             if _apply_force_interpreter_binary(args.force_interpreter_binary)
             else []
         )
+        env_overrides = get_pip_wheel_env_overrides(requirement)
+        env = os.environ.copy()
+        env.update(env_overrides)
 
         out = subprocess.run(
             [
@@ -139,6 +143,7 @@ def _apply_force_interpreter_binary(cli_flag: bool) -> bool:
             ]
             + no_binary_args
             + force_interpreter_args,
+            env=env if env_overrides else None,
             stdout=subprocess.PIPE,
             stderr=subprocess.PIPE,
         )
@@ -173,6 +178,9 @@ def _apply_force_interpreter_binary(cli_flag: bool) -> bool:
             if _apply_force_interpreter_binary(args.force_interpreter_binary)
             else []
         )
+        env_overrides = get_pip_wheel_env_overrides(requirement)
+        env = os.environ.copy()
+        env.update(env_overrides)
 
         out = subprocess.run(
             [
@@ -188,6 +196,7 @@ def _apply_force_interpreter_binary(cli_flag: bool) -> bool:
             ]
             + no_binary_args
             + force_interpreter_args,
+            env=env if env_overrides else None,
             stdout=subprocess.PIPE,
             stderr=subprocess.PIPE,
         )

exclude_list.yaml

@@ -22,7 +22,6 @@
   platform: 'darwin'
   python: '>3.11'
 
-
 - package_name: 'pygobject'
   python: '==3.8'