diff --git a/bin/xbps-fbulk/main.c b/bin/xbps-fbulk/main.c
index 4bd10b05..e54bea17 100644
--- a/bin/xbps-fbulk/main.c
+++ b/bin/xbps-fbulk/main.c
@@ -47,8 +47,6 @@
  * Only one attempt is made to build any given package, no matter how many
  * other packages depend on it.
  */
-#define _DEFAULT_SOURCE
-#define _BSD_SOURCE
 
 #include <sys/file.h>
 #include <sys/stat.h>
diff --git a/bin/xbps-query/search.c b/bin/xbps-query/search.c
index bf1bac27..98bd4c1d 100644
--- a/bin/xbps-query/search.c
+++ b/bin/xbps-query/search.c
@@ -23,12 +23,6 @@
  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
-#ifdef HAVE_STRCASESTR
-# define _GNU_SOURCE    /* for strcasestr(3) */
-#endif
-
-#include "compat.h"
-
 #include <assert.h>
 #include <errno.h>
 #include <fnmatch.h>
diff --git a/bin/xbps-uchroot/main.c b/bin/xbps-uchroot/main.c
index 410afe3b..fefa65a0 100644
--- a/bin/xbps-uchroot/main.c
+++ b/bin/xbps-uchroot/main.c
@@ -32,28 +32,28 @@
  * 	- Supports overlayfs on a temporary directory or a tmpfs mount.
  * 	- Supports read-only bind mounts.
  */
-#define _GNU_SOURCE
-#define _XOPEN_SOURCE 700
-#include <sys/types.h>
-#include <sys/prctl.h>
+
 #include <sys/fsuid.h>
 #include <sys/mount.h>
+#include <sys/prctl.h>
 #include <sys/syscall.h>
+#include <sys/types.h>
 #include <sys/wait.h>
-#include <unistd.h>
-#include <stdio.h>
-#include <fcntl.h>
-#include <errno.h>
-#include <stdarg.h>
-#include <string.h>
+
 #include <assert.h>
-#include <stdlib.h>
-#include <sched.h>
-#include <limits.h>	/* PATH_MAX */
+#include <dirent.h>
+#include <errno.h>
+#include <fcntl.h>
 #include <ftw.h>
-#include <signal.h>
 #include <getopt.h>
-#include <dirent.h>
+#include <limits.h>
+#include <sched.h>
+#include <signal.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
 
 #include <xbps.h>
 #include "queue.h"
diff --git a/bin/xbps-uunshare/main.c b/bin/xbps-uunshare/main.c
index ac257d38..8e0f5a27 100644
--- a/bin/xbps-uunshare/main.c
+++ b/bin/xbps-uunshare/main.c
@@ -22,25 +22,26 @@
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
-#define _GNU_SOURCE
-#include <sys/types.h>
-#include <sys/mount.h>
+
 #include <sys/fsuid.h>
+#include <sys/mount.h>
+#include <sys/types.h>
 #include <sys/wait.h>
+
+#include <assert.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <getopt.h>
+#include <grp.h>
+#include <limits.h>
 #include <sched.h>
+#include <signal.h>
+#include <stdarg.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
-#include <unistd.h>
-#include <stdarg.h>
-#include <signal.h>
-#include <fcntl.h>
-#include <grp.h>
-#include <errno.h>
-#include <limits.h>
 #include <syscall.h>
-#include <assert.h>
-#include <getopt.h>
+#include <unistd.h>
 
 #include <xbps.h>
 #include "queue.h"
diff --git a/configure b/configure
index 516a32ba..b5fce521 100755
--- a/configure
+++ b/configure
@@ -219,9 +219,10 @@ if [ -n "$FULL_DEBUG" ]; then
 	echo "CPPFLAGS+= -DFULL_DEBUG" >>$CONFIG_MK
 fi
 
+echo "CPPFLAGS += 	-D_DEFAULT_SOURCE" >>$CONFIG_MK
+echo "CPPFLAGS += 	-D_GNU_SOURCE" >>$CONFIG_MK
 case "$OS" in
 linux)
-	echo "CPPFLAGS += 	-D_XOPEN_SOURCE=700" >>$CONFIG_MK
 	echo "CPPFLAGS += 	-D_FILE_OFFSET_BITS=64" >> $CONFIG_MK
 	;;
 *)
diff --git a/lib/cb_util.c b/lib/cb_util.c
index 1aa0f073..35fbaa77 100644
--- a/lib/cb_util.c
+++ b/lib/cb_util.c
@@ -23,10 +23,6 @@
  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
-#ifdef HAVE_VASPRINTF
-# define _GNU_SOURCE    /* for vasprintf(3) */
-#endif
-
 #include <stdio.h>
 #include <stdbool.h>
 #include <stdlib.h>
diff --git a/lib/external/dewey.c b/lib/external/dewey.c
index 80977d9c..033d2c15 100644
--- a/lib/external/dewey.c
+++ b/lib/external/dewey.c
@@ -31,9 +31,7 @@
 #include <assert.h>
 #include <stdio.h>
 #include <stdlib.h>
-#define _BSD_SOURCE
 #include <string.h>
-#undef _BSD_SOURCE
 #include <strings.h>
 #include <ctype.h>
 
diff --git a/lib/external/fexec.c b/lib/external/fexec.c
index 11c40120..8de8ad03 100644
--- a/lib/external/fexec.c
+++ b/lib/external/fexec.c
@@ -27,19 +27,15 @@
  * POSSIBILITY OF SUCH DAMAGE.
  */
 
-#define _BSD_SOURCE	/* for vfork and chroot */
-#define _DEFAULT_SOURCE	/* glibc>=2.20 */
 #include <sys/types.h>
-#include <unistd.h>
-
 #include <sys/wait.h>
+
 #include <errno.h>
 #include <stdarg.h>
 #include <stdlib.h>
 #include <string.h>
+#include <unistd.h>
 
-#undef _DEFAULT_SOURCE
-#undef _BSD_SOURCE
 #include "xbps_api_impl.h"
 
 static int
diff --git a/lib/fetch/ftp.c b/lib/fetch/ftp.c
index 28296a00..9986a57e 100644
--- a/lib/fetch/ftp.c
+++ b/lib/fetch/ftp.c
@@ -57,11 +57,6 @@
  *
  */
 
-#ifdef __linux__
-/* Keep this down to Linux, it can create surprises else where. */
-#define _GNU_SOURCE
-#endif
-
 #include <sys/types.h>
 #include <sys/socket.h>
 
diff --git a/lib/fetch/http.c b/lib/fetch/http.c
index 0165de32..e0832865 100644
--- a/lib/fetch/http.c
+++ b/lib/fetch/http.c
@@ -62,10 +62,6 @@
  * SUCH DAMAGE.
  */
 
-#if defined(__linux__)
-#define _GNU_SOURCE
-#endif
-
 #include <sys/types.h>
 #include <sys/socket.h>
 
diff --git a/lib/portableproplib/prop_object.c b/lib/portableproplib/prop_object.c
index 2e2a7c9d..daac88cf 100644
--- a/lib/portableproplib/prop_object.c
+++ b/lib/portableproplib/prop_object.c
@@ -36,9 +36,7 @@
 static pthread_mutex_t _prop_refcnt_mtx = PTHREAD_MUTEX_INITIALIZER;
 #endif /* _PROP_NEED_REFCNT_MTX */
 
-#define __USE_MISC     /* MAP_ANON on glibc */
-# include <sys/mman.h>
-#undef __USE_MISC
+#include <sys/mman.h>
 #include <sys/stat.h>
 #include <errno.h>
 #include <fcntl.h>
diff --git a/lib/util.c b/lib/util.c
index 2e29d4d5..d5722ef4 100644
--- a/lib/util.c
+++ b/lib/util.c
@@ -22,17 +22,6 @@
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
-
-#ifdef HAVE_VASPRINTF
-# define _GNU_SOURCE	/* for vasprintf(3) */
-#endif
-
-#if defined(HAVE_STRLCAT) || defined(HAVE_STRLCPY)
-# define _BSD_SOURCE
-#endif
-
-#include "compat.h"
-
 #include <sys/utsname.h>
 
 #include <assert.h>
@@ -47,6 +36,7 @@
 #include <stdlib.h>
 #include <string.h>
 
+#include "compat.h"
 #include "xbps_api_impl.h"
 
 #ifdef __clang__