Automatic detection of the ENABLE_SIMD setting for SG:

* Scrapped the previous code
* Instead use the symbol value imported from SG via the "CONFIG" mode of CMake find_package()

CMakeLists.txt

@@ -357,23 +357,9 @@ else()
     message(STATUS "RTI: DISABLED")
 endif(ENABLE_RTI)
 
-# Check if the flag ENABLE_SIMD was enabled during the compilation of SimGear.
-# The same value has to be carried over for FlightGear to prevent crashes.
-set(INCLUDE_DIRECTORIES "${SIMGEAR_INCLUDE_DIRS}")
-foreach(dir ${CMAKE_PREFIX_PATH})
-  set(INCLUDE_DIRECTORIES "${dir}/include;${INCLUDE_DIRECTORIES}")
-endforeach()
-
-try_run(ENABLE_SIMD COMPILE_RESULT_TEST_SIMD ${CMAKE_CURRENT_BINARY_DIR}
-  ${CMAKE_CURRENT_SOURCE_DIR}/tests/test-simd-enabled.c
-  CMAKE_FLAGS "-DINCLUDE_DIRECTORIES=${INCLUDE_DIRECTORIES}")
-
-if (COMPILE_RESULT_TEST_SIMD AND ENABLE_SIMD
-    AND NOT (ENABLE_SIMD EQUAL FAILED_TO_RUN))
-  set(ENABLE_SIMD ON)
+if (ENABLE_SIMD)
   message(STATUS "SSE/SSE2 support: ENABLED")
 else()
-  set(ENABLE_SIMD OFF)
   message(STATUS "SSE/SSE2 support: DISABLED")
 endif()
 

tests/test-simd-enabled.c

@@ -1,9 +0,0 @@
-#include "simgear/simgear_config.h"
-
-int main(void) {
-  #ifdef ENABLE_SIMD
-  return 1;
-  #else
-  return 0;
-  #endif
-}