diff --git a/hadoop-common-project/hadoop-common/CHANGES.txt b/hadoop-common-project/hadoop-common/CHANGES.txt
index ce9ef402747..937eb1bdf2a 100644
--- a/hadoop-common-project/hadoop-common/CHANGES.txt
+++ b/hadoop-common-project/hadoop-common/CHANGES.txt
@@ -25,6 +25,8 @@ Release 2.6.0 - UNRELEASED
     HADOOP-10780. hadoop_user_info_alloc fails on FreeBSD due to incorrect
     sysconf use (Dmitry Sivachenko via Colin Patrick McCabe)
 
+    HADOOP-10810. Clean up native code compilation warnings. (cnauroth)
+
 Release 2.5.0 - UNRELEASED
 
   INCOMPATIBLE CHANGES
diff --git a/hadoop-common-project/hadoop-common/src/main/native/src/org/apache/hadoop/io/compress/zlib/ZlibCompressor.c b/hadoop-common-project/hadoop-common/src/main/native/src/org/apache/hadoop/io/compress/zlib/ZlibCompressor.c
index 142f5eb4064..f7c0cb9db99 100644
--- a/hadoop-common-project/hadoop-common/src/main/native/src/org/apache/hadoop/io/compress/zlib/ZlibCompressor.c
+++ b/hadoop-common-project/hadoop-common/src/main/native/src/org/apache/hadoop/io/compress/zlib/ZlibCompressor.c
@@ -379,6 +379,7 @@ Java_org_apache_hadoop_io_compress_zlib_ZlibCompressor_getLibraryName(JNIEnv *en
       return (*env)->NewStringUTF(env, dl_info.dli_fname);
     }
   }
+  return (*env)->NewStringUTF(env, "Unavailable");
 #endif
 
 #ifdef WINDOWS
diff --git a/hadoop-common-project/hadoop-common/src/main/native/src/org/apache/hadoop/io/nativeio/NativeIO.c b/hadoop-common-project/hadoop-common/src/main/native/src/org/apache/hadoop/io/nativeio/NativeIO.c
index e3ad3272423..95bb987602f 100644
--- a/hadoop-common-project/hadoop-common/src/main/native/src/org/apache/hadoop/io/nativeio/NativeIO.c
+++ b/hadoop-common-project/hadoop-common/src/main/native/src/org/apache/hadoop/io/nativeio/NativeIO.c
@@ -580,6 +580,8 @@ Java_org_apache_hadoop_io_nativeio_NativeIO_00024POSIX_getUserName(
   JNIEnv *env, jclass clazz, jint uid)
 {
 #ifdef UNIX
+  jstring jstr_username = NULL;
+  char *pw_buf = NULL;
   int pw_lock_locked = 0;
   if (pw_lock_object != NULL) {
     if ((*env)->MonitorEnter(env, pw_lock_object) != JNI_OK) {
@@ -588,7 +590,6 @@ Java_org_apache_hadoop_io_nativeio_NativeIO_00024POSIX_getUserName(
     pw_lock_locked = 1;
   }
 
-  char *pw_buf = NULL;
   int rc;
   size_t pw_buflen = get_pw_buflen();
   if ((pw_buf = malloc(pw_buflen)) == NULL) {
@@ -623,7 +624,7 @@ Java_org_apache_hadoop_io_nativeio_NativeIO_00024POSIX_getUserName(
     goto cleanup;
   }
 
-  jstring jstr_username = (*env)->NewStringUTF(env, pwd.pw_name);
+  jstr_username = (*env)->NewStringUTF(env, pwd.pw_name);
 
 cleanup:
   if (pw_lock_locked) {
@@ -664,7 +665,7 @@ Java_org_apache_hadoop_io_nativeio_NativeIO_00024POSIX_mmap(
 #ifdef WINDOWS
   THROW(env, "java/io/IOException",
     "The function POSIX.mmap() is not supported on Windows");
-  return NULL;
+  return (jlong)(intptr_t)NULL;
 #endif
 }
 
@@ -684,7 +685,6 @@ Java_org_apache_hadoop_io_nativeio_NativeIO_00024POSIX_munmap(
 #ifdef WINDOWS
   THROW(env, "java/io/IOException",
     "The function POSIX.munmap() is not supported on Windows");
-  return NULL;
 #endif
 }
 
@@ -700,6 +700,8 @@ Java_org_apache_hadoop_io_nativeio_NativeIO_00024POSIX_getGroupName(
   JNIEnv *env, jclass clazz, jint gid)
 {
 #ifdef UNIX
+  jstring jstr_groupname = NULL;
+  char *pw_buf = NULL;
   int pw_lock_locked = 0;
  
   if (pw_lock_object != NULL) {
@@ -709,7 +711,6 @@ Java_org_apache_hadoop_io_nativeio_NativeIO_00024POSIX_getGroupName(
     pw_lock_locked = 1;
   }
   
-  char *pw_buf = NULL;
   int rc;
   size_t pw_buflen = get_pw_buflen();
   if ((pw_buf = malloc(pw_buflen)) == NULL) {
@@ -744,7 +745,7 @@ Java_org_apache_hadoop_io_nativeio_NativeIO_00024POSIX_getGroupName(
     goto cleanup;
   }
 
-  jstring jstr_groupname = (*env)->NewStringUTF(env, grp.gr_name);
+  jstr_groupname = (*env)->NewStringUTF(env, grp.gr_name);
   PASS_EXCEPTIONS_GOTO(env, cleanup);
   
 cleanup:
@@ -922,7 +923,7 @@ Java_org_apache_hadoop_io_nativeio_NativeIO_00024Windows_setFilePointer
 #ifdef UNIX
   THROW(env, "java/io/IOException",
     "The function setFilePointer(FileDescriptor) is not supported on Unix");
-  return NULL;
+  return (jlong)(intptr_t)NULL;
 #endif
 
 #ifdef WINDOWS
@@ -957,7 +958,7 @@ JNIEXPORT jboolean JNICALL Java_org_apache_hadoop_io_nativeio_NativeIO_00024Wind
 #ifdef UNIX
   THROW(env, "java/io/IOException",
     "The function access0(path, access) is not supported on Unix");
-  return NULL;
+  return (jlong)(intptr_t)NULL;
 #endif
 
 #ifdef WINDOWS
diff --git a/hadoop-common-project/hadoop-common/src/main/native/src/org/apache/hadoop/net/unix/DomainSocketWatcher.c b/hadoop-common-project/hadoop-common/src/main/native/src/org/apache/hadoop/net/unix/DomainSocketWatcher.c
index 8281e643672..dbaa4fefed6 100644
--- a/hadoop-common-project/hadoop-common/src/main/native/src/org/apache/hadoop/net/unix/DomainSocketWatcher.c
+++ b/hadoop-common-project/hadoop-common/src/main/native/src/org/apache/hadoop/net/unix/DomainSocketWatcher.c
@@ -120,17 +120,19 @@ Java_org_apache_hadoop_net_unix_DomainSocketWatcher_00024FdSet_remove(
 JNIEnv *env, jobject obj, jint fd)
 {
   struct fd_set_data *sd;
-  struct pollfd *pollfd, *last_pollfd;
+  struct pollfd *pollfd = NULL, *last_pollfd;
   int used_size, i;
 
   sd = (struct fd_set_data*)(intptr_t)(*env)->
       GetLongField(env, obj, fd_set_data_fid);
   used_size = sd->used_size;
   for (i = 0; i < used_size; i++) {
-    pollfd = sd->pollfd + i;
-    if (pollfd->fd == fd) break;
+    if (sd->pollfd[i].fd == fd) {
+      pollfd = sd->pollfd + i;
+      break;
+    }
   }
-  if (i == used_size) {
+  if (pollfd == NULL) {
     (*env)->Throw(env, newRuntimeException(env, "failed to remove fd %d "
           "from the FdSet because it was never present.", fd));
     return;
diff --git a/hadoop-common-project/hadoop-common/src/main/native/src/org/apache/hadoop/security/JniBasedUnixGroupsMappingWin.c b/hadoop-common-project/hadoop-common/src/main/native/src/org/apache/hadoop/security/JniBasedUnixGroupsMappingWin.c
index 28148d09c96..5d0e449aa9f 100644
--- a/hadoop-common-project/hadoop-common/src/main/native/src/org/apache/hadoop/security/JniBasedUnixGroupsMappingWin.c
+++ b/hadoop-common-project/hadoop-common/src/main/native/src/org/apache/hadoop/security/JniBasedUnixGroupsMappingWin.c
@@ -45,7 +45,7 @@ static void throw_ioexception(JNIEnv* env, DWORD errnum)
     FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_FROM_SYSTEM,
     NULL, *(DWORD*) (&errnum), // reinterpret cast
     MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
-    (LPSTR*)&buffer, 0, NULL);
+    buffer, 0, NULL);
 
   if (len > 0)
   {