Re: [PATCH] MdePkg: DebugLib: Compilation fix for clang-13.

["Michael D Kinney" <michael.d.kinney@intel.com>]

Hi Mikhail,

For RELEASE GCC5 toolchains in tools_def.txt, I see this warning is disabled.  Likely for the same reason.

RELEASE_GCC5_IA32_CC_FLAGS       = DEF(GCC5_IA32_CC_FLAGS) -flto -Os -Wno-unused-but-set-variable -Wno-unused-const-variable
RELEASE_GCC5_X64_CC_FLAGS        = DEF(GCC5_X64_CC_FLAGS) -flto -DUSING_LTO -Os -Wno-unused-but-set-variable -Wno-unused-const-variable
RELEASE_GCC5_ARM_CC_FLAGS        = DEF(GCC5_ARM_CC_FLAGS) -flto -Wno-unused-but-set-variable -Wno-unused-const-variable
RELEASE_GCC5_AARCH64_CC_FLAGS    = DEF(GCC5_AARCH64_CC_FLAGS) -flto -Wno-unused-but-set-variable -Wno-unused-const-variable

I think it would be better to ignore the same warning in RELEASE CLANG38 tool chains with an update to tools_def.txt instead of DebugLib.h.

Unless you are thinking that disabling this warning is hiding some bad code practices that need to be cleaned up.

Best regards,

Mike


> -----Original Message-----
> From: Mikhail Krichanov <krichanov@ispras.ru>
> Sent: Friday, November 19, 2021 1:05 AM
> To: devel@edk2.groups.io
> Cc: Kinney, Michael D <michael.d.kinney@intel.com>; Liming Gao <gaoliming@byosoft.com.cn>; Liu, Zhiguang
> <zhiguang.liu@intel.com>; Vitaly Cheptsov <vit9696@protonmail.com>; Mikhail Krichanov <krichanov@ispras.ru>
> Subject: [PATCH] MdePkg: DebugLib: Compilation fix for clang-13.
> 
> build -a X64 -t CLANG38 -b RELEASE -p OvmfPkg/OvmfPkgX64.dsc
> results in
> UDK/MdeModulePkg/Library/UefiBootManagerLib/BmBoot.c:1284:31:
> error: variable 'Status' set but not used [-Werror,-Wunused-but-set-variable]
>   EFI_STATUS                  Status;
> REF: https://bugzilla.tianocore.org/show_bug.cgi?id=3704
> 
> Cc: Michael D Kinney <michael.d.kinney@intel.com>
> Cc: Liming Gao <gaoliming@byosoft.com.cn>
> Cc: Zhiguang Liu <zhiguang.liu@intel.com>
> Cc: Vitaly Cheptsov <vit9696@protonmail.com>
> Signed-off-by: Mikhail Krichanov <krichanov@ispras.ru>
> ---
>  MdePkg/Include/Library/DebugLib.h | 23 ++++++++++++++++++++---
>  1 file changed, 20 insertions(+), 3 deletions(-)
> 
> diff --git a/MdePkg/Include/Library/DebugLib.h b/MdePkg/Include/Library/DebugLib.h
> index 4cacd4b8..7785e99d 100644
> --- a/MdePkg/Include/Library/DebugLib.h
> +++ b/MdePkg/Include/Library/DebugLib.h
> @@ -370,7 +370,10 @@ UnitTestDebugAssert (
>        }                             \
>      } while (FALSE)
>  #else
> -  #define ASSERT(Expression)
> +  #define ASSERT(Expression)       \
> +    do {                           \
> +      (VOID) (Expression);         \
> +    } while (FALSE)
>  #endif
> 
>  /**
> @@ -392,6 +395,14 @@ UnitTestDebugAssert (
>          _DEBUG (Expression);       \
>        }                            \
>      } while (FALSE)
> +#elif defined(__GNUC__) || defined(__clang__)
> +  #define DEBUG(Expression)                                \
> +    do {                                                   \
> +      _Pragma("GCC diagnostic push")                       \
> +      _Pragma("GCC diagnostic ignored \"-Wunused-value\"") \
> +      (VOID) Expression;                                   \
> +      _Pragma("GCC diagnostic pop")                        \
> +    } while (FALSE)
>  #else
>    #define DEBUG(Expression)
>  #endif
> @@ -419,7 +430,10 @@ UnitTestDebugAssert (
>        }                                                                                  \
>      } while (FALSE)
>  #else
> -  #define ASSERT_EFI_ERROR(StatusParameter)
> +  #define ASSERT_EFI_ERROR(StatusParameter)                                             \
> +    do {                                                                                \
> +      (VOID) (StatusParameter);                                                         \
> +    } while (FALSE)
>  #endif
> 
>  /**
> @@ -446,7 +460,10 @@ UnitTestDebugAssert (
>        }                                                                 \
>      } while (FALSE)
>  #else
> -  #define ASSERT_RETURN_ERROR(StatusParameter)
> +  #define ASSERT_RETURN_ERROR(StatusParameter)                          \
> +    do {                                                                \
> +      (VOID) (StatusParameter);                                         \
> +    } while (FALSE)
>  #endif
> 
>  /**
> --
> 2.20.1