diff --git a/tools/hitag2crack/common/hitagcrypto.c b/tools/hitag2crack/common/hitagcrypto.c
index fc1a84051..fef25661f 100644
--- a/tools/hitag2crack/common/hitagcrypto.c
+++ b/tools/hitag2crack/common/hitagcrypto.c
@@ -208,7 +208,7 @@
 
 // We want the crypto functions to be as fast as possible, so optimize!
 // The best compiler optimization in Microchip's free XC32 edition is -O1
-#ifndef __APPLE__
+#if defined(__GNUC__) && !defined(__clang__)
 #pragma GCC optimize("O1")
 #endif
 
@@ -369,6 +369,6 @@ uint32_t hitag2_nstep(Hitag_State *pstate, uint32_t steps) {
 }
 
 // end of crypto core, revert to default optimization level
-#ifndef __APPLE__
+#if defined(__GNUC__) && !defined(__clang__)
 #pragma GCC reset_options
 #endif