Detect support for "posix_memalign" in cmake.

CMakeLists.txt

@@ -6,13 +6,15 @@ set (NUMERIC_VERSION 0x01000000)
 set (PACKAGE_VERSION 1.0.0)
 
 include (${CMAKE_ROOT}/Modules/CheckCCompilerFlag.cmake)
+include (${CMAKE_ROOT}/Modules/CheckFunctionExists.cmake)
 include (${CMAKE_ROOT}/Modules/CheckIncludeFile.cmake)
 include (${CMAKE_ROOT}/Modules/FindSDL.cmake)
 include (${CMAKE_ROOT}/Modules/FindThreads.cmake)
 
 CHECK_INCLUDE_FILE(malloc.h HAVE_MALLOC_H)
 CHECK_INCLUDE_FILE(stdint.h HAVE_STDINT_H)
 CHECK_INCLUDE_FILE(stdbool.h HAVE_STDBOOL_H)
+CHECK_FUNCTION_EXISTS(posix_memalign HAVE_POSIX_MEMALIGN)
 
 if (HAVE_MALLOC_H)
   add_definitions(-DHAVE_MALLOC_H)
@@ -23,6 +25,9 @@ endif()
 if (HAVE_STDBOOL_H)
   add_definitions(-DHAVE_STDBOOL_H)
 endif()
+if (HAVE_POSIX_MEMALIGN)
+  add_definitions(-DHAVE_POSIX_MEMALIGN)
+endif()
 
 configure_file (
   "${PROJECT_SOURCE_DIR}/libde265/de265-version.h.in"