bpo-45522: Allow to disable freelists on build time (GH-29056)

Freelists for object structs can now be disabled. A new ``configure``
option ``--without-freelists`` can be used to disable all freelists
except empty tuple singleton. Internal Py*_MAXFREELIST macros can now
be defined as 0 without causing compiler warnings and segfaults.

Signed-off-by: Christian Heimes <christian@python.org>

1 files changed, 26 insertions, 0 deletions

diff --git a/configure b/configure
index ec7c72c..198b070 100755
--- a/configure
+++ b/configure
@@ -846,6 +846,7 @@ with_dbmliborder
 enable_ipv6
 with_doc_strings
 with_pymalloc
+with_freelists
 with_c_locale_coercion
 with_valgrind
 with_dtrace
@@ -1588,6 +1589,7 @@ Optional Packages:
                           names `ndbm', `gdbm' and `bdb'.
   --with-doc-strings      enable documentation strings (default is yes)
   --with-pymalloc         enable specialized mallocs (default is yes)
+  --with-freelists        enable object freelists (default is yes)
   --with-c-locale-coercion
                           enable C locale coercion to a UTF-8 based locale
                           (default is yes)
@@ -11728,6 +11730,30 @@ fi
 { $as_echo "$as_me:${as_lineno-$LINENO}: result: $with_pymalloc" >&5
 $as_echo "$with_pymalloc" >&6; }
 
+# Check whether objects such as float, tuple and dict are using
+# freelists to optimization memory allocation.
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for --with-freelists" >&5
+$as_echo_n "checking for --with-freelists... " >&6; }
+
+# Check whether --with-freelists was given.
+if test "${with_freelists+set}" = set; then :
+  withval=$with_freelists;
+fi
+
+
+if test -z "$with_freelists"
+then
+    with_freelists="yes"
+fi
+if test "$with_freelists" != "no"
+then
+
+$as_echo "#define WITH_FREELISTS 1" >>confdefs.h
+
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $with_freelists" >&5
+$as_echo "$with_freelists" >&6; }
+
 # Check for --with-c-locale-coercion
 { $as_echo "$as_me:${as_lineno-$LINENO}: checking for --with-c-locale-coercion" >&5
 $as_echo_n "checking for --with-c-locale-coercion... " >&6; }