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block/qcow2.h: Avoid "1LL << 63" (shifts into sign bit)

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The expression "1LL << 63" tries to shift the 1 into the sign bit of a
'long long', which provokes a clang sanitizer warning:

runtime error: left shift of 1 by 63 places cannot be represented in type 'long long'

Use "1ULL << 63" as the definition of QCOW_OFLAG_COPIED instead
to avoid this. For consistency, we also update the other QCOW_OFLAG
definitions to use the ULL suffix rather than LL, though only the
shift by 63 is undefined behaviour.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This commit is contained in:
Peter Maydell 2013-08-23 17:35:45 +01:00 committed by Kevin Wolf
parent cccc30b4ad
commit 127c84e1a5
1 changed files with 3 additions and 3 deletions
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6
block/qcow2.h
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@ -40,11 +40,11 @@
#define QCOW_MAX_CRYPT_CLUSTERS 32
/* indicate that the refcount of the referenced cluster is exactly one. */
#define QCOW_OFLAG_COPIED (1LL << 63)
#define QCOW_OFLAG_COPIED (1ULL << 63)
/* indicate that the cluster is compressed (they never have the copied flag) */
#define QCOW_OFLAG_COMPRESSED (1LL << 62)
#define QCOW_OFLAG_COMPRESSED (1ULL << 62)
/* The cluster reads as all zeros */
#define QCOW_OFLAG_ZERO (1LL << 0)
#define QCOW_OFLAG_ZERO (1ULL << 0)
#define REFCOUNT_SHIFT 1 /* refcount size is 2 bytes */