gh-82616: Add Py_IS_TYPE_SIGNED() macro (#93178)

_posixsubprocess: add a static assertion to ensure that the pid_t
type is signed.

Replace _Py_IntegralTypeSigned() with _Py_IS_TYPE_SIGNED().
This commit is contained in:
Victor Stinner 2022-05-27 15:05:35 +02:00 committed by GitHub
parent cb04a09d2d
commit 22b75d9bef
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GPG Key ID: 4AEE18F83AFDEB23
4 changed files with 25 additions and 7 deletions

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@ -56,17 +56,13 @@ static inline void _Py_ADJUST_ERANGE2(double x, double y)
}
}
// Return whether integral type *type* is signed or not.
#define _Py_IntegralTypeSigned(type) \
((type)(-1) < 0)
// Return the maximum value of integral type *type*.
#define _Py_IntegralTypeMax(type) \
((_Py_IntegralTypeSigned(type)) ? (((((type)1 << (sizeof(type)*CHAR_BIT - 2)) - 1) << 1) + 1) : ~(type)0)
(_Py_IS_TYPE_SIGNED(type) ? (((((type)1 << (sizeof(type)*CHAR_BIT - 2)) - 1) << 1) + 1) : ~(type)0)
// Return the minimum value of integral type *type*.
#define _Py_IntegralTypeMin(type) \
((_Py_IntegralTypeSigned(type)) ? -_Py_IntegralTypeMax(type) - 1 : 0)
(_Py_IS_TYPE_SIGNED(type) ? -_Py_IntegralTypeMax(type) - 1 : 0)
// Check whether *v* is in the range of integral type *type*. This is most
// useful if *v* is floating-point, since demoting a floating-point *v* to an

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@ -150,4 +150,9 @@
// For example, "int x; _Py_RVALUE(x) = 1;" fails with a compiler error.
#define _Py_RVALUE(EXPR) ((void)0, (EXPR))
// Return non-zero if the type is signed, return zero if it's unsigned.
// Use "<= 0" rather than "< 0" to prevent the compiler warning:
// "comparison of unsigned expression in '< 0' is always false".
#define _Py_IS_TYPE_SIGNED(type) ((type)(-1) <= 0)
#endif /* Py_PYMACRO_H */

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@ -612,8 +612,10 @@ child_exec(char *const exec_array[],
#endif
#ifdef HAVE_SETPGID
if (pgid_to_set >= 0)
static_assert(_Py_IS_TYPE_SIGNED(pid_t), "pid_t is unsigned");
if (pgid_to_set >= 0) {
POSIX_CALL(setpgid(0, pgid_to_set));
}
#endif
#ifdef HAVE_SETGROUPS

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@ -5858,6 +5858,20 @@ settrace_to_record(PyObject *self, PyObject *list)
Py_RETURN_NONE;
}
static PyObject *
test_macros(PyObject *self, PyObject *Py_UNUSED(args))
{
// Py_MIN(), Py_MAX()
assert(Py_MIN(5, 11) == 5);
assert(Py_MAX(5, 11) == 11);
// _Py_IS_TYPE_SIGNED()
assert(_Py_IS_TYPE_SIGNED(int));
assert(!_Py_IS_TYPE_SIGNED(unsigned int));
Py_RETURN_NONE;
}
static PyObject *negative_dictoffset(PyObject *, PyObject *);
static PyObject *test_buildvalue_issue38913(PyObject *, PyObject *);
static PyObject *getargs_s_hash_int(PyObject *, PyObject *, PyObject*);
@ -6149,6 +6163,7 @@ static PyMethodDef TestMethods[] = {
{"get_feature_macros", get_feature_macros, METH_NOARGS, NULL},
{"test_code_api", test_code_api, METH_NOARGS, NULL},
{"settrace_to_record", settrace_to_record, METH_O, NULL},
{"test_macros", test_macros, METH_NOARGS, NULL},
{NULL, NULL} /* sentinel */
};