From eb928b17c5c4a3918ba1d16aed5fbd797e69e75e Mon Sep 17 00:00:00 2001
From: Laszlo Ersek <lersek@redhat.com>
Date: Sat, 9 Sep 2017 23:41:01 +0200
Subject: [PATCH] MdeModulePkg/UdfDxe: replace zero-init of local variables
 with ZeroMem()

In edk2, initialization of local variables is forbidden, both for
stylistic reasons and because such initialization may generate calls to
compiler intrinsics.

For the following initialization in UdfRead():

  CHAR16                          FileName[UDF_FILENAME_LENGTH] = { 0 };

clang-3.8 generates a memset() call, when building UdfDxe for IA32, which
then fails to link.

Replace the initialization with ZeroMem().

Do the same to "FilePath" in UdfOpen().

Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Eric Dong <eric.dong@intel.com>
Cc: Paulo Alcantara <pcacjr@zytor.com>
Cc: Ruiyu Ni <ruiyu.ni@intel.com>
Cc: Star Zeng <star.zeng@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Star Zeng <star.zeng@intel.com>
Reviewed-by: Paulo Alcantara <pcacjr@zytor.com>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
---
 MdeModulePkg/Universal/Disk/UdfDxe/File.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/MdeModulePkg/Universal/Disk/UdfDxe/File.c b/MdeModulePkg/Universal/Disk/UdfDxe/File.c
index 8b9339567f..e7159ff861 100644
--- a/MdeModulePkg/Universal/Disk/UdfDxe/File.c
+++ b/MdeModulePkg/Universal/Disk/UdfDxe/File.c
@@ -176,11 +176,12 @@ UdfOpen (
   EFI_STATUS                  Status;
   PRIVATE_UDF_FILE_DATA       *PrivFileData;
   PRIVATE_UDF_SIMPLE_FS_DATA  *PrivFsData;
-  CHAR16                      FilePath[UDF_PATH_LENGTH] = { 0 };
+  CHAR16                      FilePath[UDF_PATH_LENGTH];
   UDF_FILE_INFO               File;
   PRIVATE_UDF_FILE_DATA       *NewPrivFileData;
   CHAR16                      *TempFileName;
 
+  ZeroMem (FilePath, sizeof FilePath);
   OldTpl = gBS->RaiseTPL (TPL_CALLBACK);
 
   if (This == NULL || NewHandle == NULL || FileName == NULL) {
@@ -324,10 +325,11 @@ UdfRead (
   UDF_FILE_INFO                   FoundFile;
   UDF_FILE_IDENTIFIER_DESCRIPTOR  *NewFileIdentifierDesc;
   VOID                            *NewFileEntryData;
-  CHAR16                          FileName[UDF_FILENAME_LENGTH] = { 0 };
+  CHAR16                          FileName[UDF_FILENAME_LENGTH];
   UINT64                          FileSize;
   UINT64                          BufferSizeUint64;
 
+  ZeroMem (FileName, sizeof FileName);
   OldTpl = gBS->RaiseTPL (TPL_CALLBACK);
 
   if (This == NULL || BufferSize == NULL || (*BufferSize != 0 &&
-- 
2.39.2