From 63807139c3ee9fc6a370c77e884115a18c2b0e17 Mon Sep 17 00:00:00 2001
From: Andrey Akhmichin <15944199+nekonomicon@users.noreply.github.com>
Date: Mon, 15 Jan 2024 07:16:49 +0500
Subject: [PATCH] cmake: always use LTO if possible.

---
 CMakeLists.txt        | 8 ++++++++
 cl_dll/CMakeLists.txt | 4 ++++
 cl_dll/cl_util.h      | 3 ++-
 cl_dll/util.cpp       | 2 +-
 dlls/CMakeLists.txt   | 4 ++++
 5 files changed, 19 insertions(+), 2 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 9412d493..04cf5bce 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -33,6 +33,7 @@ set(CMAKE_MODULE_PATH ${CMAKE_MODULE_PATH} "${CMAKE_CURRENT_SOURCE_DIR}/cmake/")
 include(CheckIncludeFile)
 include(CheckCSourceCompiles)
 include(VSForceXPToolchain) # Force XP toolchain for Visual Studio
+include(CheckIPOSupported)
 
 project (HLSDK-PORTABLE)
 
@@ -152,6 +153,13 @@ if(VITA)
 	add_compile_options(-fno-use-cxa-atexit)
 endif()
 
+check_ipo_supported(RESULT HAVE_LTO OUTPUT LTO_ERROR)
+if(HAVE_LTO)
+	message(STATUS "IPO / LTO enabled")
+else()
+	message(STATUS "IPO / LTO not supported: <${LTO_ERROR}>")
+endif()
+
 check_include_file("tgmath.h" HAVE_TGMATH_H)
 if(HAVE_TGMATH_H)
 	if(NOT MSVC)
diff --git a/cl_dll/CMakeLists.txt b/cl_dll/CMakeLists.txt
index b88821a2..be856edf 100644
--- a/cl_dll/CMakeLists.txt
+++ b/cl_dll/CMakeLists.txt
@@ -208,6 +208,10 @@ if(MSVC)
 	set_property(TARGET ${CLDLL_LIBRARY} PROPERTY MSVC_RUNTIME_LIBRARY "MultiThreaded$<$<CONFIG:Debug>:Debug>")
 endif()
 
+if(HAVE_LTO)
+	set_property(TARGET ${CLDLL_LIBRARY} PROPERTY INTERPROCEDURAL_OPTIMIZATION TRUE)
+endif()
+
 install( TARGETS ${CLDLL_LIBRARY}
 	DESTINATION "${GAMEDIR}/${CLIENT_INSTALL_DIR}/"
 	PERMISSIONS OWNER_READ OWNER_WRITE OWNER_EXECUTE
diff --git a/cl_dll/cl_util.h b/cl_dll/cl_util.h
index 91615660..65275c69 100644
--- a/cl_dll/cl_util.h
+++ b/cl_dll/cl_util.h
@@ -166,7 +166,8 @@ void VectorScale( const float *in, float scale, float *out );
 float VectorNormalize( float *v );
 void VectorInverse( float *v );
 
-extern vec3_t vec3_origin;
+// extern vec3_t vec3_origin;
+extern float vec3_origin[3];
 
 // disable 'possible loss of data converting float to int' warning message
 #pragma warning( disable: 4244 )
diff --git a/cl_dll/util.cpp b/cl_dll/util.cpp
index 7d6b6669..8b5792b4 100644
--- a/cl_dll/util.cpp
+++ b/cl_dll/util.cpp
@@ -33,7 +33,7 @@
 #if !defined(M_PI_F)
 #define M_PI_F		(float)M_PI
 #endif
-extern vec3_t vec3_origin;
+// extern vec3_t vec3_origin;
 
 // if C++ mangling differs from C symbol name
 #if _MSC_VER || __WATCOMC__
diff --git a/dlls/CMakeLists.txt b/dlls/CMakeLists.txt
index 638f1a73..981a2ca1 100644
--- a/dlls/CMakeLists.txt
+++ b/dlls/CMakeLists.txt
@@ -173,6 +173,10 @@ if(MSVC)
 	set_property(TARGET ${SVDLL_LIBRARY} PROPERTY MSVC_RUNTIME_LIBRARY "MultiThreaded$<$<CONFIG:Debug>:Debug>")
 endif()
 
+if(HAVE_LTO)
+	set_property(TARGET ${SVDLL_LIBRARY} PROPERTY INTERPROCEDURAL_OPTIMIZATION TRUE)
+endif()
+
 install( TARGETS ${SVDLL_LIBRARY}
 	DESTINATION "${GAMEDIR}/${SERVER_INSTALL_DIR}/"
 	PERMISSIONS OWNER_READ OWNER_WRITE OWNER_EXECUTE