diff --git a/.clang-format b/.clang-format
index 634ebdb9..63269ac7 100644
--- a/.clang-format
+++ b/.clang-format
@@ -111,6 +111,9 @@ SpacesInCStyleCastParentheses: false
 SpacesInParentheses: false
 SpacesInSquareBrackets: false
 Standard:        Cpp11
+StatementMacros: 
+  - Q_UNUSED
+  - QT_REQUIRE_VERSION
 TabWidth:        8
 UseTab:          Never
 ...
diff --git a/doc/sources/contribute.rst b/doc/sources/contribute.rst
index a4e50173..bea72b13 100644
--- a/doc/sources/contribute.rst
+++ b/doc/sources/contribute.rst
@@ -26,14 +26,14 @@ Coding style
 We use clang-format to format source code consistently.  The
 clang-format configuration file .clang-format is located at the root
 directory.  Since clang-format produces slightly different results
-between versions, we currently use clang-format-7.
+between versions, we currently use clang-format-8.
 
 To detect any violation to the coding style, we recommend to setup git
 pre-commit hook to check coding style of the changes you introduced.
 The pre-commit file is located at the root directory.  Copy it under
 .git/hooks and make sure that it is executable.  The pre-commit script
 uses clang-format-diff.py to detect any style errors.  If it is not in
-your PATH or it exists under different name (e.g., clang-format-diff-7
+your PATH or it exists under different name (e.g., clang-format-diff-8
 in debian), either add it to PATH variable or add git option
 ``clangformatdiff.binary`` to point to the script.
 
diff --git a/src/shrpx_memcached_connection.cc b/src/shrpx_memcached_connection.cc
index d2353897..5f9aa67e 100644
--- a/src/shrpx_memcached_connection.cc
+++ b/src/shrpx_memcached_connection.cc
@@ -106,7 +106,8 @@ MemcachedConnection::MemcachedConnection(const Address *addr,
       do_read_(&MemcachedConnection::noop),
       do_write_(&MemcachedConnection::noop),
       sni_name_(sni_name),
-      connect_blocker_(gen, loop, [] {}, [] {}),
+      connect_blocker_(
+          gen, loop, [] {}, [] {}),
       parse_state_{},
       addr_(addr),
       ssl_ctx_(ssl_ctx),