diff -Naur qt-everywhere-src-5.12.4-orig/qtbase/mkspecs/features/qt_functions.prf qt-everywhere-src-5.12.4/qtbase/mkspecs/features/qt_functions.prf
--- qt-everywhere-src-5.12.4-orig/qtbase/mkspecs/features/qt_functions.prf	2019-06-12 23:59:14.000000000 +0300
+++ qt-everywhere-src-5.12.4/qtbase/mkspecs/features/qt_functions.prf	2019-06-15 15:24:17.668460200 +0300
@@ -67,40 +67,36 @@
 
 # variable, default, [suffix for variable for system() use], [prepare primary variable for system() use]
 defineTest(qtPrepareTool) {
-    cmd = $$eval(QT_TOOL.$${2}.binary)
-    isEmpty(cmd) {
-        cmd = $$[QT_HOST_BINS]/$$2
-        exists($${cmd}.pl) {
-            $${1}_EXE = $${cmd}.pl
-            cmd = perl -w $$system_path($${cmd}.pl)
+    $$1 = $$eval(QT_TOOL.$${2}.binary)
+    isEmpty($$1) {
+        $$1 = $$[QT_HOST_BINS]/$$2
+        exists($$eval($$1).pl) {
+            $${1}_EXE =  $$eval($$1).pl
+            $$1 = perl -w $$eval($$1).pl
         } else: contains(QMAKE_HOST.os, Windows) {
-            $${1}_EXE = $${cmd}.exe
-            cmd = $$system_path($${cmd}.exe)
+            $${1}_EXE = $$eval($$1).exe
+            $$1 = $$eval($$1).exe
         } else:contains(QMAKE_HOST.os, Darwin) {
-            BUNDLENAME = $${cmd}.app/Contents/MacOS/$$2
+            BUNDLENAME = $$eval($$1).app/Contents/MacOS/$$2
             exists($$BUNDLENAME) {
-                cmd = $$BUNDLENAME
+                $$1 = $$BUNDLENAME
             }
-            $${1}_EXE = $$cmd
+            $${1}_EXE = $$eval($$1).exe
         } else {
-            $${1}_EXE = $$cmd
+            $${1}_EXE = $$eval($$1).exe
         }
     } else {
-        $${1}_EXE = $$last(cmd)
+        $${1}_EXE = $$last($$eval($$1))
     }
     export($${1}_EXE)
     QT_TOOL_ENV += $$eval(QT_TOOL.$${2}.envvars)
     QT_TOOL_NAME = $$2
     !isEmpty(3)|!isEmpty(4) {
-        $$1$$3 =
-        for (arg, cmd): \
-            $$1$$3 += $$system_quote($$arg)
+        $$1$$3 = $$system_path($$eval($$1))
         qtAddTargetEnv($$1$$3, QT_TOOL.$${2}.depends, system)
     }
     isEmpty(4) {
-        $$1 =
-        for (arg, cmd): \
-            $$1 += $$shell_quote($$arg)
+        $$1 = $$shell_path($$eval($$1))
         qtAddTargetEnv($$1, QT_TOOL.$${2}.depends, )
     }
 }
diff -Naur qt-everywhere-src-5.12.4-orig/qtbase/mkspecs/features/qt_tool.prf qt-everywhere-src-5.12.4/qtbase/mkspecs/features/qt_tool.prf
--- qt-everywhere-src-5.12.4-orig/qtbase/mkspecs/features/qt_tool.prf	2019-06-12 23:59:14.000000000 +0300
+++ qt-everywhere-src-5.12.4/qtbase/mkspecs/features/qt_tool.prf	2019-06-15 15:24:17.668460200 +0300
@@ -50,15 +50,14 @@
             module_envvars =
         }
 
-        bin = $$system_path($$QMAKE_RESOLVED_TARGET)
+        bin = $$QMAKE_RESOLVED_TARGET
     } else {
         bin = $${HOST_QT_TOOLS}/$${TARGET}
         equals(QMAKE_HOST.os, Windows): bin = $${bin}.exe
-        bin = $$system_path($$bin)
     }
 
     TOOL_PRI_CONT = \
-        "QT_TOOL.$${MODULE}.binary = $$val_escape(bin)" \
+        "QT_TOOL.$${MODULE}.binary = $$bin" \
         "QT_TOOL.$${MODULE}.depends =$$join(MODULE_DEPENDS, " ", " ")" \
         $$module_envvars
     write_file($$TOOL_PRI, TOOL_PRI_CONT)|error()