From c879910102cc301904e74d08e2d08be9ed4fb125 Mon Sep 17 00:00:00 2001
From: Adam Retter <adam.retter@googlemail.com>
Date: Wed, 8 Dec 2021 21:57:57 -0800
Subject: [PATCH] Fix fstatfs call for compilation on 32 bit systems (#9251)

Summary:
On some 32-bit systems, BTRFS_SUPER_MAGIC is unsigned while __fsword_t is signed.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9251

Reviewed By: ajkr

Differential Revision: D32961651

Pulled By: pdillinger

fbshipit-source-id: 78e85fc1336f304a21e4d5961e60957c90daed63
---
 env/io_posix.cc | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/env/io_posix.cc b/env/io_posix.cc
index 8b09cce57..dbc6bec7e 100644
--- a/env/io_posix.cc
+++ b/env/io_posix.cc
@@ -1543,7 +1543,8 @@ PosixDirectory::PosixDirectory(int fd) : fd_(fd) {
 #ifdef OS_LINUX
   struct statfs buf;
   int ret = fstatfs(fd, &buf);
-  is_btrfs_ = (ret == 0 && buf.f_type == BTRFS_SUPER_MAGIC);
+  is_btrfs_ = (ret == 0 && buf.f_type == static_cast<decltype(buf.f_type)>(
+                                             BTRFS_SUPER_MAGIC));
 #endif
 }