From cca2c91058047ce6328ed7523aeef2417359e63a Mon Sep 17 00:00:00 2001
From: Leo Yuriev <leo@yuriev.ru>
Date: Mon, 4 Mar 2019 13:34:38 +0300
Subject: [PATCH] mdbx: don't check __GLIBC_PREREQ/_BSD_SOURCE/_XOPEN_SOURCE
 for use fsync (musl).

---
 src/osal.c | 5 +----
 1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/src/osal.c b/src/osal.c
index 925c43b9..be65bf99 100644
--- a/src/osal.c
+++ b/src/osal.c
@@ -673,8 +673,7 @@ int mdbx_filesync(mdbx_filehandle_t fd, bool filesize_changed) {
 #if defined(_WIN32) || defined(_WIN64)
   (void)filesize_changed;
   return FlushFileBuffers(fd) ? MDBX_SUCCESS : GetLastError();
-#elif __GLIBC_PREREQ(2, 16) || _BSD_SOURCE || _XOPEN_SOURCE ||                 \
-    (__GLIBC_PREREQ(2, 8) && _POSIX_C_SOURCE >= 200112L)
+#else
   for (;;) {
 /* LY: It is no reason to use fdatasync() here, even in case
  * no such bug in a kernel. Because "no-bug" mean that a kernel
@@ -699,8 +698,6 @@ int mdbx_filesync(mdbx_filehandle_t fd, bool filesize_changed) {
     if (rc != EINTR)
       return rc;
   }
-#else
-#error FIXME
 #endif
 }