Add more define-detection for ARM64.
Fixes #6.
diff --git a/src/utils.h b/src/utils.h
index 62de6d8..2609efa 100644
--- a/src/utils.h
+++ b/src/utils.h
@@ -62,7 +62,7 @@
defined(__sparc__) || defined(__sparc) || defined(__s390__) || \
defined(__SH4__) || defined(__alpha__) || \
defined(_MIPS_ARCH_MIPS32R2) || \
- defined(__AARCH64EL__)
+ defined(__AARCH64EL__) || defined(__aarch64__)
#define DOUBLE_CONVERSION_CORRECT_DOUBLE_OPERATIONS 1
#elif defined(__mc68000__)
#undef DOUBLE_CONVERSION_CORRECT_DOUBLE_OPERATIONS