utilities: Fix build failure with -Werror=maybe-uninitialized

Initialize magic_number to zero to avoid such failure.
utilities/blob_db/blob_log_format.cc:91:3: error: 'magic_number' may be used
uninitialized in this function [-Werror=maybe-uninitialized]
   if (magic_number != kMagicNumber) {
   ^~

Signed-off-by: He Zhe <zhe.he@windriver.com>
Signed-off-by: Khem Raj <raj.khem@gmail.com>

2 files changed, 36 insertions, 0 deletions

diff --git a/meta-oe/recipes-dbs/rocksdb/files/0001-utilities-Fix-build-failure-with-Werror-maybe-uninit.patch b/meta-oe/recipes-dbs/rocksdb/files/0001-utilities-Fix-build-failure-with-Werror-maybe-uninit.patch
new file mode 100644
index 000000000..ef0429a3c
--- /dev/null
+++ b/meta-oe/recipes-dbs/rocksdb/files/0001-utilities-Fix-build-failure-with-Werror-maybe-uninit.patch
@@ -0,0 +1,35 @@
+From 8996f075e64da0e6ffeda57632ef31f8710defcc Mon Sep 17 00:00:00 2001
+From: He Zhe <zhe.he@windriver.com>
+Date: Fri, 15 Mar 2019 16:47:03 +0800
+Subject: [PATCH] utilities: Fix build failure with -Werror=maybe-uninitialized
+
+Summary:
+Initialize magic_number to zero to avoid such failure.
+utilities/blob_db/blob_log_format.cc:91:3: error: 'magic_number' may be used
+uninitialized in this function [-Werror=maybe-uninitialized]
+   if (magic_number != kMagicNumber) {
+   ^~
+
+Upstream-Status: Accepted [expected version 5.19]
+
+Signed-off-by: He Zhe <zhe.he@windriver.com>
+---
+ utilities/blob_db/blob_log_format.cc | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/utilities/blob_db/blob_log_format.cc b/utilities/blob_db/blob_log_format.cc
+index 2bf7028..8726cb8 100644
+--- a/utilities/blob_db/blob_log_format.cc
++++ b/utilities/blob_db/blob_log_format.cc
+@@ -82,7 +82,7 @@ Status BlobLogFooter::DecodeFrom(Slice src) {
+   uint32_t src_crc = 0;
+   src_crc = crc32c::Value(src.data(), BlobLogFooter::kSize - sizeof(uint32_t));
+   src_crc = crc32c::Mask(src_crc);
+-  uint32_t magic_number;
++  uint32_t magic_number = 0;
+   if (!GetFixed32(&src, &magic_number) || !GetFixed64(&src, &blob_count) ||
+       !GetFixed64(&src, &expiration_range.first) ||
+       !GetFixed64(&src, &expiration_range.second) || !GetFixed32(&src, &crc)) {
+-- 
+2.7.4
+
diff --git a/meta-oe/recipes-dbs/rocksdb/rocksdb_git.bb b/meta-oe/recipes-dbs/rocksdb/rocksdb_git.bb
index 78520f99b..27c7b20e1 100644
--- a/meta-oe/recipes-dbs/rocksdb/rocksdb_git.bb
+++ b/meta-oe/recipes-dbs/rocksdb/rocksdb_git.bb
@@ -12,6 +12,7 @@ PV = "5.18.2"
 
 SRC_URI = "git://github.com/facebook/${BPN}.git;branch=${SRCBRANCH} \
            file://0001-Disable-Wshadow-and-do-not-mark-default-copy-constru.patch \
+           file://0001-utilities-Fix-build-failure-with-Werror-maybe-uninit.patch \
           "
 
 S = "${WORKDIR}/git"