finally fix cross-LTO on windows builds

CMakeLists.txt

@@ -13,9 +13,10 @@ option(USE_AVX2 "enable avx2 code" OFF)
 option(USE_NETNS "enable networking namespace support. Linux only" OFF)
 option(NATIVE_BUILD "optimise for host system and FPU" ON)
 option(EMBEDDED_CFG "optimise for older hardware or embedded systems" OFF)
-if (NOT MSVC)
-option(STATIC_LINK "link statically against dependencies" OFF)
-option(STATIC_LINK_RUNTIME "link statically against compiler runtime, standard library and pthreads" OFF)
+if (WIN32)
+  option(STATIC_LINK_RUNTIME "link statically against compiler runtime, standard library and pthreads" OFF)
+else()
+  option(STATIC_LINK "link statically against dependencies" OFF)
 endif()
 option(SHADOW "use shadow testing framework. linux only" OFF)
 option(XSAN "use sanitiser, if your system has it" OFF)

cmake/DownloadLibSodium.cmake

@@ -13,7 +13,12 @@ file(MAKE_DIRECTORY ${LIBSODIUM_PREFIX}/include)
 include(ExternalProject)
 include(ProcessorCount)
 
-set(SODIUM_CONFIGURE ./configure --prefix=${LIBSODIUM_PREFIX} --enable-static --disable-shared CC=${CMAKE_C_COMPILER})
+if (CMAKE_C_COMPILER_ARG1)
+  set(SODIUM_CONFIGURE ./configure --prefix=${LIBSODIUM_PREFIX} --enable-static --disable-shared CC=${CMAKE_C_COMPILER} CPPFLAGS=${CMAKE_C_COMPILER_ARG1})
+else()
+  set(SODIUM_CONFIGURE ./configure --prefix=${LIBSODIUM_PREFIX} --enable-static --disable-shared CC=${CMAKE_C_COMPILER})
+endif()
+
 if (LIBSODIUM_CROSS_TARGET)
     set(SODIUM_CONFIGURE ${SODIUM_CONFIGURE} --target=${LIBSODIUM_CROSS_TARGET} --host=${LIBSODIUM_CROSS_TARGET})
 endif()

cmake/static_link_runtime.cmake

@@ -1,38 +1,14 @@
+# This is now Win32 exclusive, other platforms can use static_link
 if(NOT STATIC_LINK_RUNTIME)
   return()
 endif()
 
-# not supported on Solaris - system libraries are not available as archives
-# LTO is supported only for native builds
-if(SOLARIS)
-  link_libraries( -static-libstdc++ -static-libgcc )
-  return()
-endif()
-
-if(NOT CMAKE_CROSSCOMPILING)
-  add_compile_options(-static -flto)
-else()
-  add_compile_options(-static)
-endif()
-
-if (CMAKE_CXX_COMPILER_ID MATCHES "Clang")
-  if(APPLE)
-    link_libraries( -flto)
-  else()
-    link_libraries( -static -static-libstdc++ -pthread -flto )
-  endif()
-
-  return()
-endif()
-
-if(NOT CMAKE_CROSSCOMPILING)
-  set(CMAKE_AR "gcc-ar")
+if (CMAKE_C_COMPILER_AR)
+  add_compile_options(-flto)
+  set(CMAKE_AR ${CMAKE_C_COMPILER_AR})
   set(CMAKE_C_ARCHIVE_CREATE "<CMAKE_AR> qcs <TARGET> <LINK_FLAGS> <OBJECTS>")
   set(CMAKE_C_ARCHIVE_FINISH "true")
   set(CMAKE_CXX_ARCHIVE_CREATE "<CMAKE_AR> qcs <TARGET> <LINK_FLAGS> <OBJECTS>")
   set(CMAKE_CXX_ARCHIVE_FINISH "true")
   link_libraries( -flto -static-libstdc++ -static-libgcc -static ${CMAKE_CXX_FLAGS} ${CRYPTO_FLAGS} )
-else()
-  set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -static-libstdc++ -static-libgcc -static" )
-  set(CMAKE_SHARED_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS}")
 endif()