support cmake LINK_LIBRARY:WHOLE_ARCHIVE

cmake/Modules/Platform/Emscripten.cmake

@@ -279,6 +279,10 @@ set(CMAKE_CXX_USE_RESPONSE_FILE_FOR_INCLUDES 1)
 set(CMAKE_C_RESPONSE_FILE_LINK_FLAG "@")
 set(CMAKE_CXX_RESPONSE_FILE_LINK_FLAG "@")
 
+# Enable $<LINK_LIBRARY:WHOLE_ARCHIVE,static_lib> for CMake 3.24+
+set(CMAKE_LINK_LIBRARY_USING_WHOLE_ARCHIVE "-Wl,--whole-archive" "<LINK_ITEM>" "-Wl,--no-whole-archive")
+set(CMAKE_LINK_LIBRARY_USING_WHOLE_ARCHIVE_SUPPORTED True)
+
 # Set a global EMSCRIPTEN variable that can be used in client CMakeLists.txt to
 # detect when building using Emscripten.
 set(EMSCRIPTEN 1 CACHE INTERNAL "If true, we are targeting Emscripten output.")

test/cmake/whole_archive/CMakeLists.txt

@@ -0,0 +1,7 @@
+cmake_minimum_required(VERSION 3.24)
+
+project(whole)
+
+add_library(whole_lib STATIC lib.cpp)
+add_executable(whole main.cpp)
+target_link_libraries(whole $<LINK_LIBRARY:WHOLE_ARCHIVE,whole_lib>)

test/cmake/whole_archive/lib.cpp

@@ -0,0 +1,6 @@
+#include <iostream>
+
+static void init(void) __attribute__((constructor));
+static void init(void) {
+    std::cout << "init" << std::endl;
+}

test/cmake/whole_archive/main.cpp

@@ -0,0 +1,5 @@
+#include <iostream>
+
+int main() {
+    std::cout << "main" << std::endl;
+}

test/cmake/whole_archive/out.txt

@@ -0,0 +1,2 @@
+init
+main

test/test_other.py

@@ -913,12 +913,13 @@ def test_emstrip(self):
     # would take 10 minutes+ to finish (CMake feature detection is slow), so
     # combine multiple features into one to try to cover as much as possible
     # while still keeping this test in sensible time limit.
-    'js':          ('target_js',      'test_cmake.js',         ['-DCMAKE_BUILD_TYPE=Debug']),
-    'html':        ('target_html',    'hello_world_gles.html', ['-DCMAKE_BUILD_TYPE=Release']),
-    'library':     ('target_library', 'libtest_cmake.a',       ['-DCMAKE_BUILD_TYPE=MinSizeRel']),
-    'static_cpp':  ('target_library', 'libtest_cmake.a',       ['-DCMAKE_BUILD_TYPE=RelWithDebInfo', '-DCPP_LIBRARY_TYPE=STATIC']),
-    'stdproperty': ('stdproperty',    'helloworld.js',         []),
-    'post_build':  ('post_build',     'hello.js',              []),
+    'js':            ('target_js',      'test_cmake.js',         ['-DCMAKE_BUILD_TYPE=Debug']),
+    'html':          ('target_html',    'hello_world_gles.html', ['-DCMAKE_BUILD_TYPE=Release']),
+    'library':       ('target_library', 'libtest_cmake.a',       ['-DCMAKE_BUILD_TYPE=MinSizeRel']),
+    'static_cpp':    ('target_library', 'libtest_cmake.a',       ['-DCMAKE_BUILD_TYPE=RelWithDebInfo', '-DCPP_LIBRARY_TYPE=STATIC']),
+    'whole_archive': ('whole_archive',  'whole.js',              []),
+    'stdproperty':   ('stdproperty',    'helloworld.js',         []),
+    'post_build':    ('post_build',     'hello.js',              []),
   })
   def test_cmake(self, test_dir, output_file, cmake_args):
     # Test all supported generators.