diff -Nru xz-5.2.4.orig/configure.ac xz-5.2.4/configure.ac
--- xz-5.2.4.orig/configure.ac	2018-04-29 18:10:38.000000000 +0300
+++ xz-5.2.4/configure.ac	2019-12-12 00:47:48.808460129 +0300
@@ -551,6 +551,7 @@
 		echo
 		echo "POSIX threading support:"
 		AX_PTHREAD([:]) dnl We don't need the HAVE_PTHREAD macro.
+		PTHREAD_LIBS="$PTHREAD_LIBS -lpthread"
 		LIBS="$LIBS $PTHREAD_LIBS"
 		AM_CFLAGS="$AM_CFLAGS $PTHREAD_CFLAGS"
 
diff -Nru xz-5.2.4.orig/Makefile.in xz-5.2.4/Makefile.in
--- xz-5.2.4.orig/Makefile.in	2018-04-29 19:01:26.000000000 +0300
+++ xz-5.2.4/Makefile.in	2019-12-12 00:48:19.857460850 +0300
@@ -351,7 +351,7 @@
 PREFERABLY_POSIX_SHELL = @PREFERABLY_POSIX_SHELL@
 PTHREAD_CC = @PTHREAD_CC@
 PTHREAD_CFLAGS = @PTHREAD_CFLAGS@
-PTHREAD_LIBS = @PTHREAD_LIBS@
+PTHREAD_LIBS = @PTHREAD_LIBS@ -lpthread
 RANLIB = @RANLIB@
 RC = @RC@
 SED = @SED@