[PATCH v2] BaseTools: align ENCODE_ERROR macro with MdePkg version

[Leif Lindholm <leif.lindholm@linaro.org>]

BaseTools' BaseTypes.h defined the ENCODE_ERROR macro as
 #define ENCODE_ERROR(a)              ((RETURN_STATUS)(MAX_BIT | (a)))
whereas MdePkg defines it as
 #define ENCODE_ERROR(StatusCode)     ((RETURN_STATUS)(MAX_BIT | (StatusCode)))

When building with GCC 6.3 (at least) the former triggers
"error: overflow in implicit constant conversion [-Werror=overflow]"
Resolve this by aligning it with the latter one.

This also requires aligning the BaseTools typedef of RETURN_STATUS with
the MdePkg one: INTN -> UINTN.

Add an explicit initialization of *Alignment to 0 in GenFfs.c
GetAlignmentFromFile to get rid of a warning occuring with GCC after
this change (-Werror=maybe-uninitialized).

Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Leif Lindholm <leif.lindholm@linaro.org>
---

Sending out a v2 because I got cought out by the leading # in the commit
message...

 BaseTools/Source/C/GenFfs/GenFfs.c            | 1 +
 BaseTools/Source/C/Include/Common/BaseTypes.h | 4 ++--
 2 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/BaseTools/Source/C/GenFfs/GenFfs.c b/BaseTools/Source/C/GenFfs/GenFfs.c
index e2fb3e0d1e..3b4a9b7761 100644
--- a/BaseTools/Source/C/GenFfs/GenFfs.c
+++ b/BaseTools/Source/C/GenFfs/GenFfs.c
@@ -529,6 +529,7 @@ GetAlignmentFromFile(char *InFile, UINT32 *Alignment)
 
   InFileHandle        = NULL;
   PeFileBuffer        = NULL;
+  *Alignment          = 0;
 
   memset (&ImageContext, 0, sizeof (ImageContext));
 
diff --git a/BaseTools/Source/C/Include/Common/BaseTypes.h b/BaseTools/Source/C/Include/Common/BaseTypes.h
index 198647ab95..5fa4e560d8 100644
--- a/BaseTools/Source/C/Include/Common/BaseTypes.h
+++ b/BaseTools/Source/C/Include/Common/BaseTypes.h
@@ -170,12 +170,12 @@
 // EFI Error Codes common to all execution phases
 //
 
-typedef INTN RETURN_STATUS;
+typedef UINTN RETURN_STATUS;
 
 ///
 /// Set the upper bit to indicate EFI Error.
 ///
-#define ENCODE_ERROR(a)              (MAX_BIT | (a))
+#define ENCODE_ERROR(a)              ((RETURN_STATUS)(MAX_BIT | (a)))
 
 #define ENCODE_WARNING(a)            (a)
 #define RETURN_ERROR(a)              ((a) < 0)
-- 
2.11.0