From 062318feb2d3b7598409c7e81e4459c2f4607764 Mon Sep 17 00:00:00 2001
From: Joerg Bornemann <joerg.bornemann@qt.io>
Date: Mon, 22 Jun 2020 18:01:30 +0200
Subject: [PATCH] CMake: Fix non-prefix build detection when
 CMAKE_STAGING_PREFIX is set

It wasn't possible to create a cross, non-prefix build with
CMAKE_INSTALL_PREFIX set to something else but the qtbase build dir
and CMAKE_STAGING_PREFIX set to the qtbase build dir.
This would be equivalent to
    configure -prefix /usr \
              -extprefix ~/my/qtbase/build/dir

Fix this by comparing the qtbase build dir against
CMAKE_STAGING_PREFIX if it is set. We also have to adjust the
QT_BUILD_DIR variable in a similar way.

Change-Id: Iaba5cf0f6954ae4b15d8af1fc62634f5d7f68835
Reviewed-by: Alexandru Croitor <alexandru.croitor@qt.io>
---
 cmake/QtBuild.cmake | 15 ++++++++++++---
 cmake/QtSetup.cmake | 17 +++++++++++++----
 2 files changed, 25 insertions(+), 7 deletions(-)

diff --git a/cmake/QtBuild.cmake b/cmake/QtBuild.cmake
index c3a9d0135d..bde23072ea 100644
--- a/cmake/QtBuild.cmake
+++ b/cmake/QtBuild.cmake
@@ -145,8 +145,13 @@ function(qt_internal_set_up_global_paths)
             set(QT_BUILD_DIR "${QtBase_BINARY_DIR}")
             set(QT_INSTALL_DIR "")
         else()
-            set(QT_BUILD_DIR "${QtBase_BINARY_DIR}")
-            set(QT_INSTALL_DIR "${QtBase_BINARY_DIR}")
+            if("${CMAKE_STAGING_PREFIX}" STREQUAL "")
+                set(QT_BUILD_DIR "${QtBase_BINARY_DIR}")
+                set(QT_INSTALL_DIR "${QtBase_BINARY_DIR}")
+            else()
+                set(QT_BUILD_DIR "${CMAKE_STAGING_PREFIX}")
+                set(QT_INSTALL_DIR "${CMAKE_STAGING_PREFIX}")
+            endif()
         endif()
     else()
         if(QT_WILL_INSTALL)
@@ -157,7 +162,11 @@ function(qt_internal_set_up_global_paths)
         else()
             # When doing a non-prefix build, both the build dir and install dir are the same,
             # pointing to the qtbase build dir.
-            set(QT_BUILD_DIR "${CMAKE_INSTALL_PREFIX}")
+            if("${CMAKE_STAGING_PREFIX}" STREQUAL "")
+                set(QT_BUILD_DIR "${CMAKE_INSTALL_PREFIX}")
+            else()
+                set(QT_BUILD_DIR "${CMAKE_STAGING_PREFIX}")
+            endif()
             set(QT_INSTALL_DIR "${QT_BUILD_DIR}")
         endif()
     endif()
diff --git a/cmake/QtSetup.cmake b/cmake/QtSetup.cmake
index b23b9924e0..bdb93e6fd0 100644
--- a/cmake/QtSetup.cmake
+++ b/cmake/QtSetup.cmake
@@ -66,21 +66,30 @@ set(CMAKE_VISIBILITY_INLINES_HIDDEN 1)
 # This detection only happens when building qtbase, and later is propagated via the generated
 # QtBuildInternalsExtra.cmake file.
 if (PROJECT_NAME STREQUAL "QtBase" AND NOT QT_BUILD_STANDALONE_TESTS)
-    if((CMAKE_INSTALL_PREFIX STREQUAL QtBase_BINARY_DIR) OR
-        (CMAKE_INSTALL_PREFIX_INITIALIZED_TO_DEFAULT AND FEATURE_developer_build))
-
-        set(__qt_will_install_value OFF)
+    if(CMAKE_INSTALL_PREFIX_INITIALIZED_TO_DEFAULT AND FEATURE_developer_build)
         # Handle non-prefix builds by setting the CMake install prefix to point to qtbase's build
         # dir.
         # While building another repo (like qtsvg) the CMAKE_PREFIX_PATH
         # should be set on the command line to point to the qtbase build dir.
         set(CMAKE_INSTALL_PREFIX ${QtBase_BINARY_DIR} CACHE PATH
             "Install path prefix, prepended onto install directories." FORCE)
+    endif()
+    if(CMAKE_CROSSCOMPILING)
+        set(__qt_prefix "${CMAKE_STAGING_PREFIX}")
+    else()
+        set(__qt_prefix_ "")
+    endif()
+    if(__qt_prefix STREQUAL "")
+        set(__qt_prefix "${CMAKE_INSTALL_PREFIX}")
+    endif()
+    if(__qt_prefix STREQUAL QtBase_BINARY_DIR)
+        set(__qt_will_install_value OFF)
     else()
         set(__qt_will_install_value ON)
     endif()
     set(QT_WILL_INSTALL ${__qt_will_install_value} CACHE BOOL
         "Boolean indicating if doing a Qt prefix build (vs non-prefix build)." FORCE)
+    unset(__qt_prefix)
     unset(__qt_will_install_value)
 endif()