CMake: Port the reduce-relocations feature

As reduce-relocations implies bsymbolic_functions, we also add the
-Bsymbolic-functions linker flag.
Also, handle the .dynlist files that are passed to the linker by
bsymbolic_functions.prf in the qmake build.

Change-Id: I535c33fba888596d2f8975b16864bbe9f0a7caa4
Reviewed-by: Alexandru Croitor <alexandru.croitor@qt.io>

cmake/QtBuild.cmake

@@ -1573,6 +1573,7 @@ function(qt_add_module target)
 
     ### Define Targets:
     set(is_interface_lib 0)
+    set(is_shared_lib 0)
     if(${arg_HEADER_MODULE})
         add_library("${target}" INTERFACE)
         set(is_interface_lib 1)
@@ -1580,6 +1581,7 @@ function(qt_add_module target)
         add_library("${target}" STATIC)
     elseif(${QT_BUILD_SHARED_LIBS})
         add_library("${target}" SHARED)
+        set(is_shared_lib 1)
     else()
         add_library("${target}" STATIC)
     endif()
@@ -1596,6 +1598,19 @@ function(qt_add_module target)
         )
     endif()
 
+    if(QT_FEATURE_reduce_relocations AND UNIX AND NOT is_interface_lib)
+        # On x86 and x86-64 systems with ELF binaries (especially Linux), due to
+        # a new optimization in GCC 5.x in combination with a recent version of
+        # GNU binutils, compiling Qt applications with -fPIE is no longer
+        # enough.
+        # Applications now need to be compiled with the -fPIC option if the Qt option
+        # \"reduce relocations\" is active.
+        target_compile_options(${target} INTERFACE -fPIC)
+        if(GCC AND is_shared_lib)
+            target_link_options(${target} PRIVATE LINKER:-Bsymbolic-functions)
+        endif()
+    endif()
+
     if (ANDROID)
         qt_android_apply_arch_suffix("${target}")
     endif()

configure.cmake

@@ -447,6 +447,12 @@ qt_feature("reduce_exports" PRIVATE
 )
 qt_feature_definition("reduce_exports" "QT_VISIBILITY_AVAILABLE")
 qt_feature_config("reduce_exports" QMAKE_PUBLIC_QT_CONFIG)
+qt_feature("reduce_relocations" PRIVATE
+    LABEL "Reduce amount of relocations"
+    CONDITION NOT WIN32 AND TEST_reduce_relocations
+)
+qt_feature_definition("reduce_relocations" "QT_REDUCE_RELOCATIONS")
+qt_feature_config("reduce_relocations" QMAKE_PUBLIC_QT_CONFIG)
 qt_feature("signaling_nan" PUBLIC
     LABEL "Signaling NaN"
     CONDITION TEST_signaling_nan

src/corelib/.prev_CMakeLists.txt

@@ -250,6 +250,10 @@ qt_add_simd_part(Core SIMD mips_dsp
         text/qstring_mips_dsp_asm.S
 )
 
+if(QT_FEATURE_reduce_relocations AND UNIX AND GCC)
+    target_link_options(Core PRIVATE
+                        "LINKER:--dynamic-list=${CMAKE_CURRENT_LIST_DIR}/QtCore.dynlist")
+endif()
 
 if(ANDROID)
     set_property(TARGET Core APPEND PROPERTY QT_ANDROID_BUNDLED_JAR_DEPENDENCIES
@@ -272,7 +276,6 @@ endif()
 # MODULE = "core"
 # MODULE_CONFIG = "moc" "resources"
 # QMAKE_DSYM_DEBUG_SCRIPT = "$$PWD/debug_script.py"
-# QMAKE_DYNAMIC_LIST_FILE = "$$PWD/QtCore.dynlist"
 # QMAKE_PKGCONFIG_VARIABLES = "host_bins" "qt_conf"
 # QMAKE_SUBSTITUTES = "ctest_macros_file" "cmake_umbrella_config_file" "cmake_umbrella_config_module_location" "cmake_umbrella_config_module_location_for_install" "cmake_umbrella_config_version_file" "cmake_extras_mkspec_dir" "cmake_extras_mkspec_dir_for_install"
 # cmake_extras_mkspec_dir.input = "$$PWD/Qt5CoreConfigExtrasMkspecDir.cmake.in"

src/corelib/CMakeLists.txt

@@ -358,6 +358,10 @@ qt_add_simd_part(Core SIMD mips_dsp
         text/qstring_mips_dsp_asm.S
 )
 
+if(QT_FEATURE_reduce_relocations AND UNIX AND GCC)
+    target_link_options(Core PRIVATE
+                        "LINKER:--dynamic-list=${CMAKE_CURRENT_LIST_DIR}/QtCore.dynlist")
+endif()
 
 if(ANDROID)
     set_property(TARGET Core APPEND PROPERTY QT_ANDROID_BUNDLED_JAR_DEPENDENCIES
@@ -380,7 +384,6 @@ endif()
 # MODULE = "core"
 # MODULE_CONFIG = "moc" "resources"
 # QMAKE_DSYM_DEBUG_SCRIPT = "$$PWD/debug_script.py"
-# QMAKE_DYNAMIC_LIST_FILE = "$$PWD/QtCore.dynlist"
 # QMAKE_PKGCONFIG_VARIABLES = "host_bins" "qt_conf"
 # QMAKE_SUBSTITUTES = "ctest_macros_file" "cmake_umbrella_config_file" "cmake_umbrella_config_module_location" "cmake_umbrella_config_module_location_for_install" "cmake_umbrella_config_version_file" "cmake_extras_mkspec_dir" "cmake_extras_mkspec_dir_for_install"
 # cmake_extras_mkspec_dir.input = "$$PWD/Qt5CoreConfigExtrasMkspecDir.cmake.in"

src/corelib/Qt6CoreConfigExtras.cmake.in

@@ -18,18 +18,6 @@ if (NOT QT_NO_CREATE_TARGETS)
     set_property(TARGET @QT_CMAKE_EXPORT_NAMESPACE@::Core APPEND PROPERTY
       COMPATIBLE_INTERFACE_STRING QT_MAJOR_VERSION QT_COORD_TYPE
     )
-
-    # On x86 and x86-64 systems with ELF binaries (especially Linux), due to
-    # a new optimization in GCC 5.x in combination with a recent version of
-    # GNU binutils, compiling Qt applications with -fPIE is no longer
-    # enough.
-    # Applications now need to be compiled with the -fPIC option if the Qt option
-    # \"reduce relocations\" is active. For backward compatibility only, Qt accepts
-    # the use of -fPIE for GCC 4.x versions.
-    if (CMAKE_CXX_COMPILER MATCHES "icc.*$" OR CMAKE_CXX_COMPILER_ID STREQUAL "GNU")
-        set_property(TARGET @QT_CMAKE_EXPORT_NAMESPACE@::Core APPEND PROPERTY INTERFACE_COMPILE_OPTIONS "-fPIC")
-    endif()
-
     if (NOT "@QT_NAMESPACE@" STREQUAL "")
         set_property(TARGET @QT_CMAKE_EXPORT_NAMESPACE@::Core APPEND PROPERTY INTERFACE_COMPILE_DEFINITIONS QT_NAMESPACE=@QT_NAMESPACE@)
     endif()

src/gui/.prev_CMakeLists.txt

@@ -241,9 +241,12 @@ qt_add_resource(Gui "qpdf"
         ${qpdf_resource_files}
 )
 
+if(QT_FEATURE_reduce_relocations AND UNIX AND GCC)
+    target_link_options(Gui PRIVATE
+                        "LINKER:--dynamic-list=${CMAKE_CURRENT_LIST_DIR}/QtGui.dynlist")
+endif()
 
 #### Keys ignored in scope 1:.:.:gui.pro:<TRUE>:
-# QMAKE_DYNAMIC_LIST_FILE = "$$PWD/QtGui.dynlist"
 # QMAKE_LIBS = "$$QMAKE_LIBS_GUI"
 
 ## Scopes:

src/gui/CMakeLists.txt

@@ -290,6 +290,11 @@ qt_add_resource(Gui "qpdf"
         ${qpdf_resource_files}
 )
 
+if(QT_FEATURE_reduce_relocations AND UNIX AND GCC)
+    target_link_options(Gui PRIVATE
+                        "LINKER:--dynamic-list=${CMAKE_CURRENT_LIST_DIR}/QtGui.dynlist")
+endif()
+
 # special case begin
 # Replace arch_haswell with avx2 feature. That is what is used in the code requireing
 # this file, too!

src/widgets/.prev_CMakeLists.txt

@@ -279,10 +279,13 @@ qt_add_resource(Widgets "qstyle1"
         ${qstyle1_resource_files}
 )
 
+if(QT_FEATURE_reduce_relocations AND UNIX AND GCC)
+    target_link_options(Widgets PRIVATE
+                        "LINKER:--dynamic-list=${CMAKE_CURRENT_LIST_DIR}/QtWidgets.dynlist")
+endif()
 
 #### Keys ignored in scope 1:.:.:widgets.pro:<TRUE>:
 # MODULE_CONFIG = "uic"
-# QMAKE_DYNAMIC_LIST_FILE = "$$PWD/QtWidgets.dynlist"
 # QMAKE_LIBS = "$$QMAKE_LIBS_GUI"
 
 ## Scopes:

src/widgets/CMakeLists.txt

@@ -281,10 +281,13 @@ qt_add_resource(Widgets "qstyle1"
         ${qstyle1_resource_files}
 )
 
+if(QT_FEATURE_reduce_relocations AND UNIX AND GCC)
+    target_link_options(Widgets PRIVATE
+                        "LINKER:--dynamic-list=${CMAKE_CURRENT_LIST_DIR}/QtWidgets.dynlist")
+endif()
 
 #### Keys ignored in scope 1:.:.:widgets.pro:<TRUE>:
 # MODULE_CONFIG = "uic"
-# QMAKE_DYNAMIC_LIST_FILE = "$$PWD/QtWidgets.dynlist"
 # QMAKE_LIBS = "$$QMAKE_LIBS_GUI"
 
 ## Scopes:

util/cmake/configurejson2cmake.py

@@ -742,7 +742,6 @@ def parseFeature(ctx, feature, data, cm_fh):
         "profile": None,
         "qmakeargs": None,
         "qpa_default_platform": None,  # Not a bool!
-        "reduce_relocations": None,
         "release": None,
         "release_tools": None,
         "rpath_dir": None,  # rpath related

util/cmake/pro2cmake.py

@@ -2519,6 +2519,19 @@ def write_simd_part(cm_fh: IO[str], target: str, scope: Scope, indent: int = 0):
         cm_fh.write(extend_scope)
 
 
+def write_reduce_relocations_part(cm_fh: IO[str], target: str, scope: Scope, indent: int = 0):
+    ind = spaces(indent)
+    dynlist_file = scope.get_files("QMAKE_DYNAMIC_LIST_FILE")
+    if dynlist_file:
+        dynlist_path = "${CMAKE_CURRENT_LIST_DIR}/" + dynlist_file[0]
+        cm_fh.write(f'{ind}if(QT_FEATURE_reduce_relocations AND UNIX AND GCC)\n')
+        ind = spaces(indent + 1)
+        cm_fh.write(f'{ind}target_link_options({target} PRIVATE\n')
+        cm_fh.write(f'{ind}                    "LINKER:--dynamic-list={dynlist_path}")\n')
+        ind = spaces(indent)
+        cm_fh.write(f'{ind}endif()\n')
+
+
 def write_android_part(cm_fh: IO[str], target: str, scope: Scope, indent: int = 0):
     keys = [
         "ANDROID_BUNDLED_JAR_DEPENDENCIES",
@@ -2825,6 +2838,8 @@ def write_main_part(
 
     write_simd_part(cm_fh, name, scope, indent)
 
+    write_reduce_relocations_part(cm_fh, name, scope, indent)
+
     write_android_part(cm_fh, name, scopes[0], indent)
 
     write_wayland_part(cm_fh, name, scopes[0], indent)