With the CLANG38 toolset (clang version 13.0.0) MdePkg fails to build in RELEASE mode because Status is only used by an assert.
edk2/MdePkg/Library/UefiMemoryAllocationLib/MemoryAllocationLib.c:141:15:
error: variable 'Status' set but not used
[-Werror,-Wunused-but-set-variable]
EFI_STATUS Status;
^
edk2/MdePkg/Library/UefiMemoryAllocationLib/MemoryAllocationLib.c:347:15:
error: variable 'Status' set but not used
[-Werror,-Wunused-but-set-variable]
EFI_STATUS Status;
^
edk2/MdePkg/Library/UefiMemoryAllocationLib/MemoryAllocationLib.c:818:15:
error: variable 'Status' set but not used
[-Werror,-Wunused-but-set-variable]
EFI_STATUS Status;
--
Rebecca Cran