update the hermetic_runtime_repo_setup to support free-threaded interpreters

Author: aignas

python/config_settings/BUILD.bazel

@@ -102,6 +102,14 @@ string_flag(
     visibility = ["//visibility:public"],
 )
 
+config_setting(
+    name = "is_py_freethreaded",
+    flag_values = {
+        ":py_freethreaded": "yes",
+    },
+    visibility = ["//visibility:public"],
+)
+
 # pip.parse related flags
 
 string_flag(

python/private/hermetic_runtime_repo_setup.bzl

@@ -50,6 +50,7 @@ def define_hermetic_runtime_toolchain_impl(
             use.
     """
     _ = name  # @unused
+    is_freethreaded = Label("//python/config_settings:is_py_freethreaded")
     version_info = semver(python_version)
     version_dict = version_info.to_dict()
     native.filegroup(
@@ -65,21 +66,27 @@ def define_hermetic_runtime_toolchain_impl(
             # Platform-agnostic filegroup can't match on all patterns.
             allow_empty = True,
             exclude = [
-                # Unused shared libraries. `python` executable and the `:libpython` target
-                # depend on `libpython{python_version}.so.1.0`.
-                "lib/libpython{major}.{minor}.so".format(**version_dict),
                 # static libraries
                 "lib/**/*.a",
+                # During pyc creation, temp files named *.pyc.NNN are created
+                "**/__pycache__/*.pyc.*",
+                # Do exclusions for all known ABIs
+                # Unused shared libraries. `python` executable and the `:libpython` target
+                # depend on `libpython{python_version}.so.1.0`.
+                "lib/libpython{major}.{minor}*.so".format(**version_dict),
+                "lib/libpython{major}.{minor}*.so".format(**version_dict),
                 # tests for the standard libraries.
-                "lib/python{major}.{minor}/**/test/**".format(**version_dict),
-                "lib/python{major}.{minor}/**/tests/**".format(**version_dict),
-                "**/__pycache__/*.pyc.*",  # During pyc creation, temp files named *.pyc.NNN are created
+                "lib/python{major}.{minor}*/**/test/**".format(**version_dict),
+                "lib/python{major}.{minor}*/**/tests/**".format(**version_dict),
             ] + glob_excludes.version_dependent_exclusions() + extra_files_glob_exclude,
         ),
     )
     cc_import(
         name = "interface",
-        interface_library = "libs/python{major}{minor}.lib".format(**version_dict),
+        interface_library = select({
+            is_freethreaded: "libs/python{major}{minor}t.lib".format(**version_dict),
+            "//conditions:default": "libs/python{major}{minor}.lib".format(**version_dict),
+        }),
         system_provided = True,
     )
 
@@ -96,14 +103,65 @@ def define_hermetic_runtime_toolchain_impl(
         hdrs = [":includes"],
         includes = [
             "include",
-            "include/python{major}.{minor}".format(**version_dict),
-            "include/python{major}.{minor}m".format(**version_dict),
+        ] + select({
+            is_freethreaded: [
+                "include/python{major}.{minor}t".format(**version_dict),
+                # FIXME @aignas 2024-11-05: the following looks fishy - should
+                # we have a config setting for `m` (i.e. DEBUG builds)?
+                "include/python{major}.{minor}tm".format(**version_dict),
+            ],
+            "//conditions:default": [
+                "include/python{major}.{minor}".format(**version_dict),
+                "include/python{major}.{minor}m".format(**version_dict),
+            ],
+        }),
+    )
+    native.config_setting(
+        name = "is_freethreaded_linux",
+        flag_values = {
+            Label("//python/config_settings:py_freethreaded"): "yes",
+        },
+        constraint_values = [
+            "@platforms//os:linux",
+        ],
+        visibility = ["//visibility:private"],
+    )
+    native.config_setting(
+        name = "is_freethreaded_osx",
+        flag_values = {
+            Label("//python/config_settings:py_freethreaded"): "yes",
+        },
+        constraint_values = [
+            "@platforms//os:osx",
+        ],
+        visibility = ["//visibility:private"],
+    )
+    native.config_setting(
+        name = "is_freethreaded_windows",
+        flag_values = {
+            Label("//python/config_settings:py_freethreaded"): "yes",
+        },
+        constraint_values = [
+            "@platforms//os:windows",
         ],
+        visibility = ["//visibility:private"],
     )
+
     cc_library(
         name = "libpython",
         hdrs = [":includes"],
         srcs = select({
+            ":is_freethreaded_linux": [
+                "lib/libpython{major}.{minor}t.so".format(**version_dict),
+                "lib/libpython{major}.{minor}t.so.1.0".format(**version_dict),
+            ],
+            ":is_freethreaded_osx": [
+                "lib/libpython{major}.{minor}t.dylib".format(**version_dict),
+            ],
+            ":is_freethreaded_windows": [
+                "python3.dll",
+                "libs/python{major}{minor}t.lib".format(**version_dict),
+            ],
             "@platforms//os:linux": [
                 "lib/libpython{major}.{minor}.so".format(**version_dict),
                 "lib/libpython{major}.{minor}.so.1.0".format(**version_dict),
@@ -137,7 +195,10 @@ def define_hermetic_runtime_toolchain_impl(
         python_version = "PY3",
         implementation_name = "cpython",
         # See https://peps.python.org/pep-3147/ for pyc tag infix format
-        pyc_tag = "cpython-{major}{minor}".format(**version_dict),
+        pyc_tag = select({
+            is_freethreaded: "cpython-{major}{minor}t".format(**version_dict),
+            "//conditions:default": "cpython-{major}{minor}".format(**version_dict),
+        }),
     )
 
     py_runtime_pair(