gh-150208: Avoid double-quoting string values in sysconfigdata (#150209)

String values from ``pyconfig.h`` were rendered into ``sysconfigdata``
variables, retaining the quotes.

Author: stefanor

Lib/sysconfig/__init__.py

@@ -437,6 +437,7 @@ def parse_config_h(fp, vars=None):
     import re
     define_rx = re.compile("#define ([A-Z][A-Za-z0-9_]+) (.*)\n")
     undef_rx = re.compile("/[*] #undef ([A-Z][A-Za-z0-9_]+) [*]/\n")
+    quoted_re = re.compile('^"(.*)"$')
 
     while True:
         line = fp.readline()
@@ -445,6 +446,8 @@ def parse_config_h(fp, vars=None):
         m = define_rx.match(line)
         if m:
             n, v = m.group(1, 2)
+            if mq := quoted_re.match(v):
+                v = mq.group(1)
             try:
                 if n in _ALWAYS_STR:
                     raise ValueError

Lib/test/test_sysconfig.py

@@ -576,6 +576,12 @@ def test_linux_ext_suffix(self):
                 expected_suffixes = 'x86_64-linux-gnu.so', 'x86_64-linux-musl.so'
             self.assertEndsWith(suffix, expected_suffixes)
 
+    @unittest.skipIf(sysconfig.get_config_var('PY_BUILTIN_HASHLIB_HASHES') is None,
+                     'PY_BUILTIN_HASHLIB_HASHES required for this test')
+    def test_PY_BUILTIN_HASHLIB_HASHES_in_vars(self):
+        vars = sysconfig.get_config_vars()
+        self.assertFalse(vars['PY_BUILTIN_HASHLIB_HASHES'].startswith('"'))
+
     @unittest.skipUnless(sys.platform == 'android', 'Android-specific test')
     def test_android_ext_suffix(self):
         machine = platform.machine()

Misc/NEWS.d/next/Core_and_Builtins/2026-05-21-21-04-43.gh-issue-150208.VOkxRG.rst

@@ -0,0 +1,2 @@
+Avoid double-quoting string values from ``pyconfig.h`` in ``sysconfigdata``
+variables.