Re: [edk2-devel] [edk2-platforms] [PATCH v3] Platform/ARM/SgiPkg: Fix constant-logical-operand clang error

["Ard Biesheuvel" <ard.biesheuvel@arm.com>]

On 11/27/20 11:45 AM, Vijayenthiran Subramanian wrote:
> Hi Ard,
> 
> On Wed, Nov 25, 2020 at 3:05 PM Ard Biesheuvel <ard.biesheuvel@arm.com> wrote:
>>
>> On 11/25/20 3:30 PM, Vijayenthiran Subramaniam wrote:
>>> Fix "use of logical '&&' with constant operand" error when built with
>>> CLANG38 toolchain.
>>>
>>> Reviewed-by: Thomas Abraham <thomas.abraham@arm.com>
>>> Signed-off-by: Vijayenthiran Subramaniam <vijayenthiran.subramaniam@arm.com>
>>> ---
>>>
>>> Changes since v2:
>>>     - Reviewed-bys added from:
>>>       https://edk2.groups.io/g/devel/topic/71391950#55868
>>>     - Rebased to latest master and repost.
>>>
>>> Changes since v1:
>>>     - Fix Copyright year
>>>
>>> Note:
>>>       Fix Clan error reported by Leif in
>>>       https://edk2.groups.io/g/devel/message/54586
>>>
>>>    Platform/ARM/SgiPkg/Drivers/PlatformDxe/VirtioDevices.c | 10 +++++-----
>>>    1 file changed, 5 insertions(+), 5 deletions(-)
>>>
>>> diff --git a/Platform/ARM/SgiPkg/Drivers/PlatformDxe/VirtioDevices.c b/Platform/ARM/SgiPkg/Drivers/PlatformDxe/VirtioDevices.c
>>> index 9e5f7e70..f91724b9 100644
>>> --- a/Platform/ARM/SgiPkg/Drivers/PlatformDxe/VirtioDevices.c
>>> +++ b/Platform/ARM/SgiPkg/Drivers/PlatformDxe/VirtioDevices.c
>>> @@ -1,6 +1,6 @@
>>>    /** @file
>>>
>>> -  Copyright (c) 2018, ARM Ltd. All rights reserved.<BR>
>>> +  Copyright (c) 2018-2020, ARM Limited. All rights reserved.
>>>
>>>      SPDX-License-Identifier: BSD-2-Clause-Patent
>>>
>>> @@ -81,8 +81,8 @@ InitVirtioDevices (
>>>      STATIC EFI_HANDLE mVirtIoNetController = NULL;
>>>
>>>      // Install protocol interface for storage device
>>> -  if ((FeaturePcdGet (PcdVirtioBlkSupported)) &&
>>> -      (FixedPcdGet32 (PcdVirtioBlkBaseAddress))) {
>>> +  if ((FeaturePcdGet (PcdVirtioBlkSupported) == TRUE) &&
>>> +      (FixedPcdGet32 (PcdVirtioBlkBaseAddress) != 0)) {
>>
>> Nack
>>
>> Please fix this by disabling this bogus warning in the compiler. The
>> original code is perfectly reasonable, and comparing a boolean
>> expression to TRUE could equally trigger a diagnostic in another
>> compiler for being redundant. (The != 0 check for a UINT32 is fine)
> 
> As you suggested, Boolean comparison with TRUE is not required for
> CLANG as well. But != 0 check for UINT32 is required to fix the error while
> building with the CLANG toolchain profile. Would it be ok if I post another
> version with just != 0 check with UNT32?
> 

Yes, that is fine.