Add PCH builds via 'SFML_ENABLE_PCH' CMake option

CMakeLists.txt

@@ -288,6 +288,17 @@ if(SFML_INSTALL_PKGCONFIG_FILES)
     endforeach()
 endif()
 
+# option to enable precompiled headers
+sfml_set_option(SFML_ENABLE_PCH FALSE BOOL "TRUE to enable precompiled headers for SFML builds -- only supported on Windows/Linux and for static library builds")
+
+if(SFML_ENABLE_PCH AND BUILD_SHARED_LIBS)
+    message(FATAL_ERROR "Precompiled headers are currently not supported for shared library builds")
+endif()
+
+if(SFML_ENABLE_PCH AND SFML_OS_MACOSX)
+    message(FATAL_ERROR "Precompiled headers are currently not supported in MacOS builds")
+endif()
+
 # setup the install rules
 if(NOT SFML_BUILD_FRAMEWORKS)
     install(DIRECTORY include

cmake/Macros.cmake

@@ -3,6 +3,14 @@ include(CMakeParseArguments)
 # include the compiler warnings helpers
 include(${CMAKE_CURRENT_LIST_DIR}/CompilerWarnings.cmake)
 
+# helper function to tweak visibility of public symbols
+function(set_public_symbols_hidden target)
+    # ensure public symbols are hidden by default (exported ones are explicitly marked)
+    set_target_properties(${target} PROPERTIES
+                          CXX_VISIBILITY_PRESET hidden
+                          VISIBILITY_INLINES_HIDDEN YES)
+endfunction()
+
 # This little macro lets you set any Xcode specific property
 macro(sfml_set_xcode_property TARGET XCODE_PROPERTY XCODE_VALUE)
     set_property (TARGET ${TARGET} PROPERTY XCODE_ATTRIBUTE_${XCODE_PROPERTY} ${XCODE_VALUE})
@@ -80,6 +88,13 @@ macro(sfml_add_library module)
     endif()
 
     set_target_warnings(${target})
+    set_public_symbols_hidden(${target})
+
+    # enable precompiled headers
+    if (SFML_ENABLE_PCH AND (NOT ${target} STREQUAL "sfml-system"))
+        message(VERBOSE "enabling PCH for SFML library '${target}'")
+        target_precompile_headers(${target} REUSE_FROM sfml-system)
+    endif()
 
     # define the export symbol of the module
     string(REPLACE "-" "_" NAME_UPPER "${target}")
@@ -163,6 +178,14 @@ macro(sfml_add_library module)
             set_target_properties(${target} PROPERTIES
                                   PDB_NAME "${target}${SFML_PDB_POSTFIX}"
                                   PDB_OUTPUT_DIRECTORY "${PROJECT_BINARY_DIR}/lib")
+        else()
+            if(SFML_ENABLE_PCH)
+                message(VERBOSE "overriding PDB name for '${target}' with \"sfml-s${SFML_PDB_POSTFIX}\" due to PCH being enabled")
+
+                # For PCH builds with PCH reuse, the PDB name must be the same as the target that's being reused
+                set_target_properties(${target} PROPERTIES
+                                      COMPILE_PDB_NAME "sfml-system"
+                                      COMPILE_PDB_OUTPUT_DIRECTORY "${PROJECT_BINARY_DIR}/lib")
             else()
                 # Static libraries have no linker PDBs, thus the compiler PDBs are relevant
                 set_target_properties(${target} PROPERTIES
@@ -170,11 +193,7 @@ macro(sfml_add_library module)
                                       COMPILE_PDB_OUTPUT_DIRECTORY "${PROJECT_BINARY_DIR}/lib")
             endif()
         endif()
-
+    endif()
-    # ensure public symbols are hidden by default (exported ones are explicitly marked)
-    set_target_properties(${target} PROPERTIES
-                          CXX_VISIBILITY_PRESET hidden
-                          VISIBILITY_INLINES_HIDDEN YES)
 
     # build frameworks or dylibs
     if(SFML_OS_MACOSX AND BUILD_SHARED_LIBS AND NOT THIS_STATIC)
@@ -285,7 +304,14 @@ macro(sfml_add_example target)
         set_property(TARGET ${target} PROPERTY MSVC_RUNTIME_LIBRARY "MultiThreaded$<$<CONFIG:Debug>:Debug>")
     endif()
 
+    # enable precompiled headers
+    if (SFML_ENABLE_PCH)
+        message(VERBOSE "enabling PCH for SFML example '${target}'")
+        target_precompile_headers(${target} REUSE_FROM sfml-system)
+    endif()
+
     set_target_warnings(${target})
+    set_public_symbols_hidden(${target})
 
     # set the debug suffix
     set_target_properties(${target} PROPERTIES DEBUG_POSTFIX -d)
@@ -322,6 +348,12 @@ function(sfml_add_test target SOURCES DEPENDS)
     # create the target
     add_executable(${target} ${SOURCES})
 
+    # enable precompiled headers
+    if (SFML_ENABLE_PCH)
+        message(VERBOSE "enabling PCH for SFML test '${target}'")
+        target_precompile_headers(${target} REUSE_FROM sfml-system)
+    endif()
+
     # set the target's folder (for IDEs that support it, e.g. Visual Studio)
     set_target_properties(${target} PROPERTIES FOLDER "Tests")
 
@@ -329,6 +361,7 @@ function(sfml_add_test target SOURCES DEPENDS)
     target_link_libraries(${target} PRIVATE ${DEPENDS} sfml-test-main)
 
     set_target_warnings(${target})
+    set_public_symbols_hidden(${target})
 
     # If coverage is enabled for MSVC and we are linking statically, use /WHOLEARCHIVE
     # to make sure the linker doesn't discard unused code sections before coverage can be measured

src/SFML/PCH.hpp

@@ -0,0 +1,62 @@
+////////////////////////////////////////////////////////////
+//
+// SFML - Simple and Fast Multimedia Library
+// Copyright (C) 2007-2022 Laurent Gomila (laurent@sfml-dev.org)
+//
+// This software is provided 'as-is', without any express or implied warranty.
+// In no event will the authors be held liable for any damages arising from the use of this software.
+//
+// Permission is granted to anyone to use this software for any purpose,
+// including commercial applications, and to alter it and redistribute it freely,
+// subject to the following restrictions:
+//
+// 1. The origin of this software must not be misrepresented;
+//    you must not claim that you wrote the original software.
+//    If you use this software in a product, an acknowledgment
+//    in the product documentation would be appreciated but is not required.
+//
+// 2. Altered source versions must be plainly marked as such,
+//    and must not be misrepresented as being the original software.
+//
+// 3. This notice may not be removed or altered from any source distribution.
+//
+////////////////////////////////////////////////////////////
+
+#ifndef SFML_SFML_PCH_HPP
+#define SFML_SFML_PCH_HPP
+
+////////////////////////////////////////////////////////////
+// Precompiled Headers
+////////////////////////////////////////////////////////////
+
+#include <SFML/Config.hpp>
+
+#ifdef SFML_SYSTEM_WINDOWS
+
+#define UNICODE  1
+#define _UNICODE 1
+#include <SFML/System/Win32/WindowsHeader.hpp>
+
+#endif // SFML_SYSTEM_WINDOWS
+
+#include <SFML/System/Err.hpp>
+#include <SFML/System/String.hpp>
+#include <SFML/System/Time.hpp>
+#include <SFML/System/Vector2.hpp>
+
+#include <algorithm>
+#include <cassert>
+#include <chrono>
+#include <cmath>
+#include <cstdint>
+#include <cstring>
+#include <filesystem>
+#include <iostream>
+#include <memory>
+#include <mutex>
+#include <ostream>
+#include <string>
+#include <unordered_map>
+#include <vector>
+
+#endif // SFML_SFML_PCH_HPP

src/SFML/System/CMakeLists.txt

@@ -67,6 +67,12 @@ endif()
 sfml_add_library(System
                  SOURCES ${SRC} ${PLATFORM_SRC})
 
+# enable precompiled headers
+if (SFML_ENABLE_PCH)
+    message(VERBOSE "enabling PCH for SFML library 'sfml-system' (reused as the PCH for other SFML libraries)")
+    target_precompile_headers(sfml-system PRIVATE ${PROJECT_SOURCE_DIR}/src/SFML/PCH.hpp)
+endif()
+
 if(SFML_OS_ANDROID)
     # glad sources
     target_include_directories(sfml-system PRIVATE "${PROJECT_SOURCE_DIR}/extlibs/headers/glad/include")