Replace unsafe PY_*_VERSION comparisons to fix for Python 4.0 (#14280)

`#if PY_MAJOR_VERSION >= 3 && PY_MINOR_VERSION >= 7`

For example, this is true for Python 3.7-3.11 but also true for Python
4.7-4.11. Instead, `PY_VERSION_HEX` should be used.

https://docs.python.org/3.11/c-api/apiabiversion.html

```c
/* Version as a single 4-byte hex number, e.g. 0x010502B2 == 1.5.2b2.
   Use this for numeric comparisons, e.g. #if PY_VERSION_HEX >= ... */
```

https://github.com/python/cpython/blob/2e279e85fece187b6058718ac7e82d1692461e26/Include/patchlevel.h#L29-L30

Remove compatibility code that only applied to EOL and unsupported
Python versions (<= 3.6)

Author: hugovk

mypy/stubtest.py

@@ -1533,9 +1533,6 @@ def get_typeshed_stdlib_modules(
     stdlib_py_versions = mypy.modulefinder.load_stdlib_py_versions(custom_typeshed_dir)
     if version_info is None:
         version_info = sys.version_info[0:2]
-    # Typeshed's minimum supported Python 3 is Python 3.7
-    if sys.version_info < (3, 7):
-        version_info = (3, 7)
 
     def exists_in_version(module: str) -> bool:
         assert version_info is not None

mypyc/common.py

@@ -44,13 +44,6 @@
 
 PLATFORM_SIZE = 4 if IS_32_BIT_PLATFORM else 8
 
-# Python 3.5 on macOS uses a hybrid 32/64-bit build that requires some workarounds.
-# The same generated C will be compiled in both 32 and 64 bit modes when building mypy
-# wheels (for an unknown reason).
-#
-# Note that we use "in ['darwin']" because of https://github.com/mypyc/mypyc/issues/761.
-IS_MIXED_32_64_BIT_BUILD: Final = sys.platform in ["darwin"] and sys.version_info < (3, 6)
-
 # Maximum value for a short tagged integer.
 MAX_SHORT_INT: Final = 2 ** (8 * int(SIZEOF_SIZE_T) - 2) - 1
 
@@ -59,9 +52,8 @@
 
 # Maximum value for a short tagged integer represented as a C integer literal.
 #
-# Note: Assume that the compiled code uses the same bit width as mypyc, except for
-#       Python 3.5 on macOS.
-MAX_LITERAL_SHORT_INT: Final = MAX_SHORT_INT if not IS_MIXED_32_64_BIT_BUILD else 2**30 - 1
+# Note: Assume that the compiled code uses the same bit width as mypyc
+MAX_LITERAL_SHORT_INT: Final = MAX_SHORT_INT
 MIN_LITERAL_SHORT_INT: Final = -MAX_LITERAL_SHORT_INT - 1
 
 # Decription of the C type used to track the definedness of attributes and

mypyc/lib-rt/CPy.h

@@ -499,13 +499,8 @@ static inline bool CPy_KeepPropagating(void) {
 }
 // We want to avoid the public PyErr_GetExcInfo API for these because
 // it requires a bunch of spurious refcount traffic on the parts of
-// the triple we don't care about. Unfortunately the layout of the
-// data structure changed in 3.7 so we need to handle that.
-#if PY_MAJOR_VERSION >= 3 && PY_MINOR_VERSION >= 7
+// the triple we don't care about.
 #define CPy_ExcState() PyThreadState_GET()->exc_info
-#else
-#define CPy_ExcState() PyThreadState_GET()
-#endif
 
 void CPy_Raise(PyObject *exc);
 void CPy_Reraise(void);
@@ -527,7 +522,7 @@ void CPy_AttributeError(const char *filename, const char *funcname, const char *
 
 // Misc operations
 
-#if PY_MAJOR_VERSION >= 3 && PY_MINOR_VERSION >= 8
+#if PY_VERSION_HEX >= 0x03080000
 #define CPy_TRASHCAN_BEGIN(op, dealloc) Py_TRASHCAN_BEGIN(op, dealloc)
 #define CPy_TRASHCAN_END(op) Py_TRASHCAN_END
 #else

mypyc/lib-rt/getargsfast.c

@@ -18,9 +18,6 @@
 #include <Python.h>
 #include "CPy.h"
 
-/* None of this is supported on Python 3.6 or earlier */
-#if PY_VERSION_HEX >= 0x03070000
-
 #define PARSER_INITED(parser) ((parser)->kwtuple != NULL)
 
 /* Forward */
@@ -570,5 +567,3 @@ skipitem_fast(const char **p_format, va_list *p_va)
 
     *p_format = format;
 }
-
-#endif

mypyc/lib-rt/pythonsupport.h

@@ -22,7 +22,6 @@ extern "C" {
 
 /////////////////////////////////////////
 // Adapted from bltinmodule.c in Python 3.7.0
-#if PY_MAJOR_VERSION >= 3 && PY_MINOR_VERSION >= 7
 _Py_IDENTIFIER(__mro_entries__);
 static PyObject*
 update_bases(PyObject *bases)
@@ -96,16 +95,8 @@ update_bases(PyObject *bases)
     Py_XDECREF(new_bases);
     return NULL;
 }
-#else
-static PyObject*
-update_bases(PyObject *bases)
-{
-    return bases;
-}
-#endif
 
 // From Python 3.7's typeobject.c
-#if PY_MAJOR_VERSION >= 3 && PY_MINOR_VERSION >= 6
 _Py_IDENTIFIER(__init_subclass__);
 static int
 init_subclass(PyTypeObject *type, PyObject *kwds)
@@ -134,14 +125,6 @@ init_subclass(PyTypeObject *type, PyObject *kwds)
     return 0;
 }
 
-#else
-static int
-init_subclass(PyTypeObject *type, PyObject *kwds)
-{
-    return 0;
-}
-#endif
-
 // Adapted from longobject.c in Python 3.7.0
 
 /* This function adapted from PyLong_AsLongLongAndOverflow, but with
@@ -306,7 +289,7 @@ list_count(PyListObject *self, PyObject *value)
     return CPyTagged_ShortFromSsize_t(count);
 }
 
-#if PY_MAJOR_VERSION >= 3 && PY_MINOR_VERSION < 8
+#if PY_VERSION_HEX < 0x03080000
 static PyObject *
 _PyDict_GetItemStringWithError(PyObject *v, const char *key)
 {
@@ -321,13 +304,7 @@ _PyDict_GetItemStringWithError(PyObject *v, const char *key)
 }
 #endif
 
-#if PY_MAJOR_VERSION >= 3 && PY_MINOR_VERSION < 6
-/* _PyUnicode_EqualToASCIIString got added in 3.5.3 (argh!) so we can't actually know
- * whether it will be present at runtime, so we just assume we don't have it in 3.5. */
-#define CPyUnicode_EqualToASCIIString(x, y) (PyUnicode_CompareWithASCIIString((x), (y)) == 0)
-#elif PY_MAJOR_VERSION >= 3 && PY_MINOR_VERSION >= 6
 #define CPyUnicode_EqualToASCIIString(x, y) _PyUnicode_EqualToASCIIString(x, y)
-#endif
 
 // Adapted from genobject.c in Python 3.7.2
 // Copied because it wasn't in 3.5.2 and it is undocumented anyways.
@@ -390,7 +367,7 @@ _CPyDictView_New(PyObject *dict, PyTypeObject *type)
 }
 #endif
 
-#if PY_MAJOR_VERSION >= 3 && PY_MINOR_VERSION >=10
+#if PY_VERSION_HEX >= 0x030A0000  // 3.10
 static int
 _CPyObject_HasAttrId(PyObject *v, _Py_Identifier *name) {
     PyObject *tmp = NULL;
@@ -404,7 +381,7 @@ _CPyObject_HasAttrId(PyObject *v, _Py_Identifier *name) {
 #define _CPyObject_HasAttrId _PyObject_HasAttrId
 #endif
 
-#if PY_MAJOR_VERSION >= 3 && PY_MINOR_VERSION < 9
+#if PY_VERSION_HEX < 0x03090000
 // OneArgs and NoArgs functions got added in 3.9
 #define _PyObject_CallMethodIdNoArgs(self, name) \
     _PyObject_CallMethodIdObjArgs((self), (name), NULL)