diff --git a/bison.pri b/bison.pri
index fcfad6f8..14e2e01f 100644
--- a/bison.pri
+++ b/bison.pri
@@ -17,7 +17,13 @@ win32 {
   QMAKE_EXTRA_COMPILERS += bison_header
 }
 
-unix:freebsd-g++ {
+unix:linux* {
+  exists(/usr/bin/bison) {
+    QMAKE_YACC = /usr/bin/bison
+  }
+}
+
+freebsd* {
   # on bsd /usr/bin/bison is outdated, dont use it
   exists(/usr/local/bin/bison) {
     QMAKE_YACC = /usr/local/bin/bison
@@ -26,16 +32,10 @@ unix:freebsd-g++ {
   }
 }
 
-unix:netbsd* {
+netbsd* {
   exists(/usr/pkg/bin/bison) {
     QMAKE_YACC = /usr/pkg/bin/bison
   } else { # look in $PATH
     QMAKE_YACC = bison
   }
 }
-
-unix:linux* {
-  exists(/usr/bin/bison) {
-    QMAKE_YACC = /usr/bin/bison
-  }
-}
diff --git a/eigen.pri b/eigen.pri
index 5dd32792..fd7ac746 100644
--- a/eigen.pri
+++ b/eigen.pri
@@ -49,13 +49,13 @@ CONFIG(mingw-cross-env) {
 isEmpty(EIGEN_INCLUDEPATH) {
   freebsd-g++: EIGEN_INCLUDEPATH = /usr/local/include/eigen3
   macx: EIGEN_INCLUDEPATH = /opt/local/include/eigen3
-  linux*|hurd*: EIGEN_INCLUDEPATH = /usr/include/eigen3
   netbsd*: EIGEN_INCLUDEPATH = /usr/pkg/include/eigen3
-  !exists($$EIGEN_INCLUDEPATH) {
+  linux*|hurd*|unix: EIGEN_INCLUDEPATH = /usr/include/eigen3
+  isEmpty(EIGEN_INCLUDEPATH) {
     freebsd-g++: EIGEN_INCLUDEPATH = /usr/local/include/eigen2
     macx: EIGEN_INCLUDEPATH = /opt/local/include/eigen2
-    linux*|hurd*: EIGEN_INCLUDEPATH = /usr/include/eigen2
     netbsd*: EIGEN_INCLUDEPATH = /usr/pkg/include/eigen2
+    linux*|hurd*|unix*: EIGEN_INCLUDEPATH = /usr/include/eigen2
   }
 }
 
diff --git a/flex.pri b/flex.pri
index 57f854e0..203d90d2 100644
--- a/flex.pri
+++ b/flex.pri
@@ -9,16 +9,17 @@ win32 {
   QMAKE_EXTRA_COMPILERS += flex
 }
 
-unix:freebsd-g++ {
-  QMAKE_LEX = /usr/local/bin/flex
-}
-
-unix:netbsd* {
-  QMAKE_LEX = /usr/pkg/bin/flex
-}
-
 unix:linux* {
   exists(/usr/bin/flex) {
     QMAKE_LEX = /usr/bin/flex
   }
 }
+
+freebsd* {
+  QMAKE_LEX = /usr/local/bin/flex
+}
+
+netbsd* {
+  QMAKE_LEX = /usr/pkg/bin/flex
+}
+
diff --git a/glew.pri b/glew.pri
index f4a6ccd0..9898af59 100644
--- a/glew.pri
+++ b/glew.pri
@@ -6,7 +6,6 @@ glew {
     QMAKE_INCDIR += $$GLEW_DIR/include
     QMAKE_LIBDIR += $$GLEW_DIR/lib
     QMAKE_LIBDIR += $$GLEW_DIR/lib64
-    message("GLEW location: $$GLEW_DIR")
   }
 
   unix:LIBS += -lGLEW
diff --git a/openscad.pro b/openscad.pro
index 49b764f6..6d9556bc 100644
--- a/openscad.pro
+++ b/openscad.pro
@@ -116,11 +116,6 @@ netbsd* {
 	QMAKE_CXXFLAGS_WARN_ON += -Wno-sign-compare
 }
 
-CONFIG(skip-version-check) {
-  # force the use of outdated libraries
-  DEFINES += OPENSCAD_SKIP_VERSION_CHECK
-}
-
 # Application configuration
 macx:CONFIG += mdi
 CONFIG += cgal
@@ -144,6 +139,12 @@ CONFIG(mingw-cross-env) {
   include(mingw-cross-env.pri)
 }
 
+# force the use of outdated libraries
+CONFIG(skip-version-check) {
+  DEFINES += OPENSCAD_SKIP_VERSION_CHECK
+}
+
+
 win32 {
   FLEXSOURCES = src/lexer.l
   BISONSOURCES = src/parser.y