[PATCH v4 1/3] memtx: renamed memtx_tree.c to memtx_tree.cc

[Kirill Shcherbatov <kshcherbatov@tarantool.org>]

Changed memtx_tree source extension to use C++ compiler. We need
it as we going to use templates and class methods in further
patches.

Needed for #3961
---
 src/box/CMakeLists.txt                  | 2 +-
 src/box/{memtx_tree.c => memtx_tree.cc} | 3 ++-
 2 files changed, 3 insertions(+), 2 deletions(-)
 rename src/box/{memtx_tree.c => memtx_tree.cc} (99%)

diff --git a/src/box/CMakeLists.txt b/src/box/CMakeLists.txt
index 59e91b65a..d4d9b7aeb 100644
--- a/src/box/CMakeLists.txt
+++ b/src/box/CMakeLists.txt
@@ -64,7 +64,7 @@ add_library(box STATIC
     index_def.c
     iterator_type.c
     memtx_hash.c
-    memtx_tree.c
+    memtx_tree.cc
     memtx_rtree.c
     memtx_bitset.c
     engine.c
diff --git a/src/box/memtx_tree.c b/src/box/memtx_tree.cc
similarity index 99%
rename from src/box/memtx_tree.c
rename to src/box/memtx_tree.cc
index 250df7f2d..9c2bcbf8e 100644
--- a/src/box/memtx_tree.c
+++ b/src/box/memtx_tree.cc
@@ -564,7 +564,8 @@ memtx_tree_index_create_iterator(struct index *base, enum iterator_type type,
 		key = NULL;
 	}
 
-	struct tree_iterator *it = mempool_alloc(&memtx->iterator_pool);
+	struct tree_iterator *it =
+		(struct tree_iterator *)mempool_alloc(&memtx->iterator_pool);
 	if (it == NULL) {
 		diag_set(OutOfMemory, sizeof(struct tree_iterator),
 			 "memtx_tree_index", "iterator");
-- 
2.21.0