CMake: Fix many failing qtdeclarative MinGW tests

A lot of qtdeclarative tests fail due to not finding the
QtTest qml plugin in ${prefix}/qml. This is just the symptom, the
problem is that the combination of CMake + MinGW + Qt relocatability
behaves incorrectly.

The value returned by
QLibraryInfo::location(QLibraryInfo::Qml2ImportsPath) for the
qmltestrunner executable is ${prefix}/bin/qml which is incorrect.

This happens due to a combination of things. The
c33916a279ef5908e1ebd44644c873933f6a7c77 change in qtbase introduced
checks to figure out whether an application is a windeployqt-ed app
to adjust the prefix path.

This check tries to find the import library libQt6Core.a in the lib
subfolder whenever the executed app dir path is equal to the
computed prefix path.

If it's found, the code assumes we are running a tool in
${prefix}/bin. If it's not found, the code assumes it's a
windeployqt'ed app, where the Qt .dlls are next to the executable.

Currently when QtCore is built with CMake targeting MinGW, we actually
create a libQt6Core.dll file instead of a Qt6Core.dll file, and also
an import library called libQt6Core.dll.a, instead of libQt6Core.a.

The prefix check code actually prepends an additional "lib", thus
trying to find the liblibQt6Core.a import library.

This fails, the code assumes a windeployqt'ed app, and returns the
currently executed app path dir as the prefix aka ${prefix}/bin in
the case of qmltestrunner, and thus none of the qml plugins are found.

To fix this, generated the shared library and the import library names
as qmake expects them, aka Qt6Core.dll and libQt6Core.a.

Some of this renaming was done for MinGW plugins and shared libraries,
but not for modules in 9b0e23ef8a915a8c58808fa356f771ecdb6f020c.

Extract the duplicate code and apply it to all shared libraries built
by Qt on Windows. Adjust the prefix and suffix accordingly, depending
on whether we use MinGW or not.

Amends 9b0e23ef8a915a8c58808fa356f771ecdb6f020c

Task-number: QTBUG-84886
Change-Id: I5a8618597df5f57ce256739adced3f24eb13dac7
Reviewed-by: Cristian Adam <cristian.adam@qt.io>
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>

1 files changed, 19 insertions, 8 deletions

diff --git a/cmake/QtBuild.cmake b/cmake/QtBuild.cmake
index e4d501f1f6..3ab3e80e0d 100644
--- a/cmake/QtBuild.cmake
+++ b/cmake/QtBuild.cmake
@@ -2395,6 +2395,8 @@ function(qt_add_module target)
             )
         endif()
 
+        qt_internal_apply_win_prefix_and_suffix("${target}")
+
         if (WIN32 AND BUILD_SHARED_LIBS)
             qt6_generate_win32_rc_file(${target})
         endif()
@@ -3230,10 +3232,7 @@ function(qt_internal_add_plugin target)
             # but Qt plugins are actually suffixed with .dylib.
             set_property(TARGET "${target}" PROPERTY SUFFIX ".dylib")
         endif()
-        if(WIN32)
-            # CMake sets for Windows-GNU platforms the suffix "lib"
-            set_property(TARGET "${target}" PROPERTY PREFIX "")
-        endif()
+        qt_internal_apply_win_prefix_and_suffix("${target}")
     endif()
 
     qt_set_common_target_properties(${target})
@@ -3999,6 +3998,7 @@ function(qt_add_cmake_library target)
         add_library("${target}" STATIC)
     elseif(${arg_SHARED})
         add_library("${target}" SHARED)
+        qt_internal_apply_win_prefix_and_suffix("${target}")
     elseif(${arg_MODULE})
         add_library("${target}" MODULE)
         set_property(TARGET ${name} PROPERTY C_VISIBILITY_PRESET default)
@@ -4009,10 +4009,7 @@ function(qt_add_cmake_library target)
             # but Qt plugins are actually suffixed with .dylib.
             set_property(TARGET "${target}" PROPERTY SUFFIX ".dylib")
         endif()
-        if(WIN32)
-            # CMake sets for Windows-GNU platforms the suffix "lib"
-            set_property(TARGET "${target}" PROPERTY PREFIX "")
-        endif()
+        qt_internal_apply_win_prefix_and_suffix("${target}")
     else()
         add_library("${target}")
     endif()
@@ -5438,6 +5435,20 @@ function(qt_internal_set_up_sanitizer_features)
     endif()
 endfunction()
 
+function(qt_internal_apply_win_prefix_and_suffix target)
+    if(WIN32)
+        # CMake sets for Windows-GNU platforms the prefix "lib", whereas qmake expects
+        # no prefix.
+        set_property(TARGET "${target}" PROPERTY PREFIX "")
+
+        # CMake sets for Windows-GNU platforms the import suffix "dll.a", whereas qmake
+        # expects an ".a" import suffix.
+        if(MINGW)
+            set_property(TARGET "${target}" PROPERTY IMPORT_SUFFIX ".a")
+        endif()
+    endif()
+endfunction()
+
 # Compatibility macros that should be removed once all their usages are removed.
 function(extend_target)
     qt_extend_target(${ARGV})