+# Allocating Aligned Memory Blocks
+include(CheckIncludeFiles)
+check_include_files(malloc.h OPJ_HAVE_MALLOC_H)
+include(CheckSymbolExists)
+# _aligned_alloc https://msdn.microsoft.com/en-us/library/8z34s9c6.aspx
+check_symbol_exists(_aligned_malloc malloc.h OPJ_HAVE__ALIGNED_MALLOC)
+# posix_memalign (needs _POSIX_C_SOURCE >= 200112L on Linux)
+set(CMAKE_REQUIRED_DEFINITIONS -D_POSIX_C_SOURCE=200112L)
+check_symbol_exists(posix_memalign stdlib.h OPJ_HAVE_POSIX_MEMALIGN)
+unset(CMAKE_REQUIRED_DEFINITIONS)
+# memalign (obsolete)
+check_symbol_exists(memalign malloc.h OPJ_HAVE_MEMALIGN)