Distinguish AppleClang from LLVM on ARM64

Author: martin-frbg

c_check

@@ -335,7 +335,14 @@ if [ "$architecture" = "arm64" ]; then
 fi
 
 no_sme=0
+is_appleclang=0
 if [ "$architecture" = "arm64" ]; then
+    if [ "$compiler" = "CLANG" ]; then
+        data=`$compiler_name --version`
+	case "$data" in Apple*)
+	is_appleclang=1
+	esac
+    fi
     tmpd=$(mktemp -d 2>/dev/null || mktemp -d -t 'OBC')
     tmpf="$tmpd/a.S"
     printf ".text \n.global sme_test\n\nsme_test:\nsmstart\nsmstop\nret\n">> "$tmpf"
@@ -469,6 +476,7 @@ done
     [ "$no_avx512bf" -eq 1 ] && printf "NO_AVX512BF16=1\n"
     [ "$no_avx2" -eq 1 ] && printf "NO_AVX2=1\n"
     [ "$oldgcc" -eq 1 ] && printf "OLDGCC=1\n"
+    [ "$is_appleclang" -eq 1 ] && printf "APPLECLANG=1\n"
     exit 0
 }
 
@@ -499,6 +507,7 @@ done
     [ "$no_avx512bf" -eq 1 ] && printf "NO_AVX512BF16=1\n"
     [ "$no_avx2" -eq 1 ] && printf "NO_AVX2=1\n"
     [ "$oldgcc" -eq 1 ] && printf "OLDGCC=1\n"
+    [ "$is_appleclang" -eq 1 ] && printf "APPLECLANG=1\n"
     [ "$no_lsx" -eq 1 ] && printf "NO_LSX=1\n"
     [ "$no_lasx" -eq 1 ] && printf "NO_LASX=1\n"
 } >> "$makefile"