qmake: don't misuse cache()

... when QMAKE_DEFAULT_{INC,LIB}DIRS cannot be determined. it would have been nicer to actually persist empty results, but cache() won't do that, and fixing it doesn't seem worth the effort now. Change-Id: I95d5645e40a0da572f0def16462703373eaeb804 Reviewed-by: Joerg Bornemann <[email protected]>
boris-fx · Dec 14, 2018 · 852b1af · 852b1af
1 parent 74cdd89
commit 852b1af
Showing 1 changed file with 5 additions and 2 deletions.
diff --git a/mkspecs/features/toolchain.prf b/mkspecs/features/toolchain.prf
@@ -183,8 +183,11 @@ isEmpty($${target_prefix}.INCDIRS) {
         isEmpty(QMAKE_DEFAULT_LIBDIRS): QMAKE_DEFAULT_LIBDIRS = /lib /usr/lib
     }
 
-    cache($${target_prefix}.INCDIRS, set stash, QMAKE_DEFAULT_INCDIRS)
-    cache($${target_prefix}.LIBDIRS, set stash, QMAKE_DEFAULT_LIBDIRS)
+    # cache() complains about undefined variables and doesn't persist empty ones.
+    !isEmpty(QMAKE_DEFAULT_INCDIRS): \
+        cache($${target_prefix}.INCDIRS, set stash, QMAKE_DEFAULT_INCDIRS)
+    !isEmpty(QMAKE_DEFAULT_LIBDIRS): \
+        cache($${target_prefix}.LIBDIRS, set stash, QMAKE_DEFAULT_LIBDIRS)
 } else {
     QMAKE_DEFAULT_INCDIRS = $$eval($${target_prefix}.INCDIRS)
     QMAKE_DEFAULT_LIBDIRS = $$eval($${target_prefix}.LIBDIRS)