audk/PcAtChipsetPkg/Library
Michael Kinney bbd61de5db PcAtChipsetPkg/SerialIoLib: Remove negative value shift
https://bugzilla.tianocore.org/show_bug.cgi?id=553

Remove left shift of negative values that always evaluate
to 0 to address build errors from the llvm/clang compiler
used in the XCODE5 tool chain.

Clang rightfully complains about left-shifting ~DLAB. DLAB is #defined
as 0x01 (an "int"), hence ~DLAB has value (-2) on all edk2 platforms.
Left-shifting a negative int is undefined behavior.

Rather than replacing ~DLAB with ~(UINT32)DLAB, realize that the nonzero
bits of (~(UINT32)DLAB << 7) would all be truncated away in the final
conversion to UINT8 anyway. So just remove (~DLAB << 7).

Cc: Ruiyu Ni <ruiyu.ni@intel.com>
Cc: Andrew Fish <afish@apple.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Michael D Kinney <michael.d.kinney@intel.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
2017-05-19 12:12:06 -07:00
..
AcpiTimerLib PcAtChipsetPkg AcpiTimerLib: Clear bits [31:24] after reading by IoRead32() 2016-10-11 13:02:43 +08:00
BaseIoApicLib
ResetSystemLib
SerialIoLib PcAtChipsetPkg/SerialIoLib: Remove negative value shift 2017-05-19 12:12:06 -07:00