diff --git a/configure.json b/configure.json
index a079572c0a..bf0416417b 100644
--- a/configure.json
+++ b/configure.json
@@ -858,14 +858,10 @@
             "test": "unix/reduce_relocs"
         },
         "skip_modules": {
-            "description": "modules to skip",
-            "type": "skipModules",
-            "log": "value"
+            "type": "skipModules"
         },
         "build_parts": {
-            "description": "parts of Qt to build",
-            "type": "buildParts",
-            "log": "value"
+            "type": "buildParts"
         },
         "dlopen": {
             "description": "dlopen() in libc",
@@ -2104,7 +2100,6 @@
             "output": [ { "type": "varAssign", "name": "QT_SKIP_MODULES", "value": "tests.skip_modules.value" } ]
         },
         "build_parts": {
-            "description": "Qt build parts",
             "output": [ { "type": "varAppend", "name": "QT_BUILD_PARTS", "value": "tests.build_parts.value" } ]
         },
         "qreal": {
diff --git a/configure.pri b/configure.pri
index bd899073c4..21ceb68d33 100644
--- a/configure.pri
+++ b/configure.pri
@@ -203,6 +203,9 @@ defineTest(qtConfTest_neon) {
 }
 
 defineTest(qtConfTest_skipModules) {
+    $${1}.cache = -
+    export($${1}.cache)
+
     skip =
     uikit {
         skip += qtdoc qtmacextras qtserialport qtwebkit qtwebkit-examples
@@ -220,8 +223,6 @@ defineTest(qtConfTest_skipModules) {
     }
     $${1}.value = $$unique(skip)
     export($${1}.value)
-    $${1}.cache += value
-    export($${1}.cache)
     return(true)
 }
 
@@ -243,7 +244,7 @@ defineTest(qtConfTest_buildParts) {
 
     $${1}.value = $$parts
     export($${1}.value)
-    $${1}.cache += value
+    $${1}.cache = -
     export($${1}.cache)
     return(true)
 }
diff --git a/mkspecs/features/qt_configure.prf b/mkspecs/features/qt_configure.prf
index 9b388ab556..64f0f48400 100644
--- a/mkspecs/features/qt_configure.prf
+++ b/mkspecs/features/qt_configure.prf
@@ -789,6 +789,8 @@ defineTest(qtLogTestResult) {
 }
 
 defineTest(qtConfSaveResult) {
+    equals($${1}.cache, -): \
+        return()
     keys = result $$eval($${1}.cache)
     cont = "cache.$${2}._KEYS_ = $$keys"
     for (k, keys): \