From 8ef4edc09ea27ef301c866f812481cf0697cbfba Mon Sep 17 00:00:00 2001
From: Joerg Bornemann <joerg.bornemann@qt.io>
Date: Mon, 20 Apr 2020 20:31:31 +0200
Subject: [PATCH] CMake: Fix handling of negated feature config values

Consider a negated feature config value like the following:
qt_feature_config("foo" QMAKE_PUBLIC_QT_CONFIG NEGATE)

If this feature was disabled, it would turn up in both,
enabled_features and disabled_features of module .pri files.
Also, QT_CONFIG would contain foo.

Expected however is that QT_CONFIG contains no-foo, and only
disabled_features contains foo.

Fix this by prepending a "no_" prefix to the value, similar to the
"no-" prefix in the qmake build. The qt_correct_config function was
adjusted to recognize "no_foo" and translate it to the qmakeish
"no-foo" config value.

Config values that start with "no_" but do not correspond to a feature
are left untouched. You can still have values like
"no_valley_too_deep" or "no_mountain_too_high".

Change-Id: I23d8b18c84e04ea6dfa25cc6ccd8f7e86211b144
Reviewed-by: Alexandru Croitor <alexandru.croitor@qt.io>
---
 cmake/QtBuild.cmake   | 18 ++++++++++++++++--
 cmake/QtFeature.cmake | 11 ++++++-----
 2 files changed, 22 insertions(+), 7 deletions(-)

diff --git a/cmake/QtBuild.cmake b/cmake/QtBuild.cmake
index 5fa81fe807a..2ade160779a 100644
--- a/cmake/QtBuild.cmake
+++ b/cmake/QtBuild.cmake
@@ -696,12 +696,26 @@ endfunction()
 function(qt_correct_config out_var config)
     set(corrected_config "")
     foreach(name ${config})
+        # Is the config value a known feature?
         get_property(feature_original_name GLOBAL PROPERTY "QT_FEATURE_ORIGINAL_NAME_${name}")
         if(feature_original_name)
             list(APPEND corrected_config "${feature_original_name}")
-        else()
-            list(APPEND corrected_config "${name}")
+            continue()
         endif()
+
+        # Is the config value a negated known feature, e.g. no_foo?
+        # Then add the config value no-foo.
+        if(name MATCHES "^no_(.*)")
+            get_property(feature_original_name GLOBAL PROPERTY
+                "QT_FEATURE_ORIGINAL_NAME_${CMAKE_MATCH_1}")
+            if(feature_original_name)
+                list(APPEND corrected_config "no-${feature_original_name}")
+                continue()
+            endif()
+        endif()
+
+        # The config value is no known feature. Add the value as is.
+        list(APPEND corrected_config "${name}")
     endforeach()
     set(${out_var} ${corrected_config} PARENT_SCOPE)
 endfunction()
diff --git a/cmake/QtFeature.cmake b/cmake/QtFeature.cmake
index 4cf7c0f9466..52475dfa853 100644
--- a/cmake/QtFeature.cmake
+++ b/cmake/QtFeature.cmake
@@ -312,16 +312,17 @@ function(qt_evaluate_qmake_config_values key)
         "FEATURE;NAME;CONFIG_VAR_NAME"
         "" ${${key}})
 
-    set(expected "NOT")
-    if (arg_NEGATE)
-        set(expected "")
-    endif()
-
     # If no custom name is specified, then the config value is the same as the feature name.
     if(NOT arg_NAME)
         set(arg_NAME "${arg_FEATURE}")
     endif()
 
+    set(expected "NOT")
+    if (arg_NEGATE)
+        set(expected "")
+        string(PREPEND arg_NAME "no_")
+    endif()
+
     # The feature condition is false, there is no need to export any config values.
     if(${expected} ${QT_FEATURE_${arg_FEATURE}})
         return()