python315: init add 3.15.0a1

https://docs.python.org/3.15/whatsnew/changelog.html#python-3-15-0-alpha-1

doc/languages-frameworks/python.section.md

@@ -55,6 +55,7 @@ sets are
 * `pkgs.python312Packages`
 * `pkgs.python313Packages`
 * `pkgs.python314Packages`
+* `pkgs.python315Packages`
 * `pkgs.pypy27Packages`
 * `pkgs.pypy310Packages`
 

pkgs/development/interpreters/python/cpython/3.15/no-ldconfig.patch

@@ -0,0 +1,40 @@
+diff --git a/Lib/ctypes/util.py b/Lib/ctypes/util.py
+index 378f12167c6..21710702e69 100644
+--- a/Lib/ctypes/util.py
++++ b/Lib/ctypes/util.py
+@@ -374,34 +374,7 @@ def find_library(name, is64 = False):
+     else:
+ 
+         def _findSoname_ldconfig(name):
+-            import struct
+-            if struct.calcsize('l') == 4:
+-                machine = os.uname().machine + '-32'
+-            else:
+-                machine = os.uname().machine + '-64'
+-            mach_map = {
+-                'x86_64-64': 'libc6,x86-64',
+-                'ppc64-64': 'libc6,64bit',
+-                'sparc64-64': 'libc6,64bit',
+-                's390x-64': 'libc6,64bit',
+-                'ia64-64': 'libc6,IA-64',
+-                }
+-            abi_type = mach_map.get(machine, 'libc6')
+-
+-            # XXX assuming GLIBC's ldconfig (with option -p)
+-            regex = r'\s+(lib%s\.[^\s]+)\s+\(%s'
+-            regex = os.fsencode(regex % (re.escape(name), abi_type))
+-            try:
+-                with subprocess.Popen(['/sbin/ldconfig', '-p'],
+-                                      stdin=subprocess.DEVNULL,
+-                                      stderr=subprocess.DEVNULL,
+-                                      stdout=subprocess.PIPE,
+-                                      env={'LC_ALL': 'C', 'LANG': 'C'}) as p:
+-                    res = re.search(regex, p.stdout.read())
+-                    if res:
+-                        return os.fsdecode(res.group(1))
+-            except OSError:
+-                pass
++            return None
+ 
+         def _findLib_ld(name):
+             # See issue #9998 for why this is needed

pkgs/development/interpreters/python/default.nix

@@ -97,6 +97,19 @@
       hash = "sha256-Ipna5ULTlc44g6ygDTyRAwfNaOCy9zNgmMjnt+7p8+k=";
       inherit passthruFun;
     };
+
+    python315 = callPackage ./cpython {
+      self = __splicedPackages.python315;
+      sourceVersion = {
+        major = "3";
+        minor = "15";
+        patch = "0";
+        suffix = "a1";
+      };
+      hash = "sha256-MZSTnUiO6u79z5kNNVQtmtHOeIeJxOIwWiBg63BY5aQ=";
+      inherit passthruFun;
+    };
+
     # Minimal versions of Python (built without optional dependencies)
     python3Minimal =
       (callPackage ./cpython (

pkgs/top-level/all-packages.nix

@@ -5942,6 +5942,11 @@ with pkgs;
     pythonAttr = "python314FreeThreading";
     enableGIL = false;
   };
+  python315FreeThreading = python315.override {
+    self = python315FreeThreading;
+    pythonAttr = "python315FreeThreading";
+    enableGIL = false;
+  };
 
   pythonInterpreters = callPackage ./../development/interpreters/python { };
   inherit (pythonInterpreters)
@@ -5951,6 +5956,7 @@ with pkgs;
     python312
     python313
     python314
+    python315
     python3Minimal
     pypy27
     pypy310
@@ -5967,6 +5973,7 @@ with pkgs;
   python312Packages = recurseIntoAttrs python312.pkgs;
   python313Packages = recurseIntoAttrs python313.pkgs;
   python314Packages = python314.pkgs;
+  python315Packages = python315.pkgs;
   pypyPackages = pypy.pkgs;
   pypy2Packages = pypy2.pkgs;
   pypy27Packages = pypy27.pkgs;