Issue #6493: Fix a ctypes problem setting bitfields more than 31 bits
wide.
diff --git a/Lib/ctypes/test/test_bitfields.py b/Lib/ctypes/test/test_bitfields.py
index e9c46c2..211d1db 100644
--- a/Lib/ctypes/test/test_bitfields.py
+++ b/Lib/ctypes/test/test_bitfields.py
@@ -240,5 +240,20 @@
_anonymous_ = ["_"]
_fields_ = [("_", X)]
+ def test_uint32(self):
+ class X(Structure):
+ _fields_ = [("a", c_uint32, 32)]
+ x = X()
+ x.a = 10
+ self.failUnlessEqual(x.a, 10)
+
+ def test_uint64(self):
+ class X(Structure):
+ _fields_ = [("a", c_uint64, 64)]
+ x = X()
+ x.a = 10
+ self.failUnlessEqual(x.a, 10)
+
+
if __name__ == "__main__":
unittest.main()
diff --git a/Misc/NEWS b/Misc/NEWS
index 77e3ac6..d175786 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -349,6 +349,8 @@
Library
-------
+- Issue #6493: Fix a ctypes problem setting bitfields more than 31 bits wide.
+
- unittest has been split up into a package. All old names should still work.
- Issue #6431: Make Fraction type return NotImplemented when it doesn't
diff --git a/Modules/_ctypes/cfield.c b/Modules/_ctypes/cfield.c
index bf247bc..7663481 100644
--- a/Modules/_ctypes/cfield.c
+++ b/Modules/_ctypes/cfield.c
@@ -426,9 +426,9 @@
#define LOW_BIT(x) ((x) & 0xFFFF)
#define NUM_BITS(x) ((x) >> 16)
-/* This seems nore a compiler issue than a Windows/non-Windows one */
+/* This seems more a compiler issue than a Windows/non-Windows one */
#ifdef MS_WIN32
-# define BIT_MASK(size) ((1 << NUM_BITS(size))-1)
+# define BIT_MASK(size) ((1i64 << NUM_BITS(size))-1)
#else
# define BIT_MASK(size) ((1LL << NUM_BITS(size))-1)
#endif