fix build on older macOs releases, aligned_alloc only from catalina.

closes #549

src/alloc-override.c

@@ -16,6 +16,7 @@ terms of the MIT license. A copy of the license can be found in the file
 #if defined(MI_MALLOC_OVERRIDE) && !(defined(_WIN32)) 
 
 #if defined(__APPLE__)
+#include <AvailabilityMacros.h>
 mi_decl_externc void   vfree(void* p);
 mi_decl_externc size_t malloc_size(const void* p);
 mi_decl_externc size_t malloc_good_size(size_t size);
@@ -77,7 +78,9 @@ typedef struct mi_nothrow_s { int _tag; } mi_nothrow_t;
     MI_INTERPOSE_MI(valloc),
     MI_INTERPOSE_MI(malloc_size),
     MI_INTERPOSE_MI(malloc_good_size),
+    #if defined(MAC_OS_X_VERSION_10_15) && MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_15 
     MI_INTERPOSE_MI(aligned_alloc),
+    #endif
     #ifdef MI_OSX_ZONE
     // we interpose malloc_default_zone in alloc-override-osx.c so we can use mi_free safely
     MI_INTERPOSE_MI(free),

src/random.c

@@ -195,6 +195,7 @@ static bool os_random_buf(void* buf, size_t buf_len) {
 #elif defined(__APPLE__)
 #include <AvailabilityMacros.h>
 #if defined(MAC_OS_X_VERSION_10_10) && MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_10
+#include <CommonCrypto/CommonCryptoError.h>
 #include <CommonCrypto/CommonRandom.h>
 #endif
 static bool os_random_buf(void* buf, size_t buf_len) {