Apply -lpthread withou windows.

sqlite3.go

@@ -9,7 +9,6 @@ package sqlite3
 #cgo CFLAGS: -std=gnu99
 #cgo CFLAGS: -DSQLITE_ENABLE_RTREE -DSQLITE_THREADSAFE
 #cgo CFLAGS: -DSQLITE_ENABLE_FTS3 -DSQLITE_ENABLE_FTS3_PARENTHESIS
-#cgo LDFLAGS: -lpthread
 #include <sqlite3-binding.h>
 #include <stdlib.h>
 #include <string.h>

sqlite3_other.go

@@ -9,6 +9,6 @@ package sqlite3
 /*
 #cgo CFLAGS: -I.
 #cgo linux LDFLAGS: -ldl
-#cgo CFLAGS: -DSQLITE_ENABLE_RTREE -DSQLITE_THREADSAFE
+#cgo LDFLAGS: -lpthread
 */
 import "C"

sqlite3_windows.go

@@ -2,6 +2,7 @@
 //
 // Use of this source code is governed by an MIT-style
 // license that can be found in the LICENSE file.
+// +build windows
 
 package sqlite3