--- QtSingleApplication-2.6.1/buildlib/buildlib.pro.orig	2015-06-29 15:40:53.000000000 +0200
+++ QtSingleApplication-2.6.1/buildlib/buildlib.pro	2018-12-31 18:20:11.008121897 +0100
@@ -5,9 +5,12 @@
 include(../src/qtsingleapplication.pri)
 TARGET = $$QTSINGLEAPPLICATION_LIBNAME
 DESTDIR = $$QTSINGLEAPPLICATION_LIBDIR
+isEmpty(INSTALL_LIBDIR) {
+  INSTALL_LIBDIR = $$QTSINGLEAPPLICATION_LIBDIR
+}
 win32 {
     DLLDESTDIR = $$[QT_INSTALL_BINS]
     QMAKE_DISTCLEAN += $$[QT_INSTALL_BINS]\\$${QTSINGLEAPPLICATION_LIBNAME}.dll
 }
-target.path = $$DESTDIR
+target.path = $$INSTALL_LIBDIR
 INSTALLS += target
--- QtSingleApplication-2.6.1/buildlib/buildcorelib.pro.orig	2018-12-31 18:05:26.731465328 +0100
+++ QtSingleApplication-2.6.1/buildlib/buildcorelib.pro	2018-12-31 18:20:37.364788263 +0100
@@ -5,9 +5,12 @@
 include(../src/qtsinglecoreapplication.pri)
 TARGET = $$QTSINGLECOREAPPLICATION_LIBNAME
 DESTDIR = $$QTSINGLEAPPLICATION_LIBDIR
+isEmpty(INSTALL_LIBDIR) {
+  INSTALL_LIBDIR = $$QTSINGLEAPPLICATION_LIBDIR
+}
 win32 {
     DLLDESTDIR = $$[QT_INSTALL_BINS]
     QMAKE_DISTCLEAN += $$[QT_INSTALL_BINS]\\$${QTSINGLECOREAPPLICATION_LIBNAME}.dll
 }
-target.path = $$DESTDIR
+target.path = $$INSTALL_LIBDIR
 INSTALLS += target