diff --git a/ggml-quants.c b/ggml-quants.c
index 42bf749e9..5e4da4d37 100644
--- a/ggml-quants.c
+++ b/ggml-quants.c
@@ -1273,8 +1273,12 @@ static float make_qkx2_quants(int n, int nmax, const float * restrict x, const f
     float max = x[0];
     float sum_w = weights[0];
     float sum_x = sum_w * x[0];
-    // Mark i as volatile to prevent the -O3 optimizer from unrolling this loop and breaking MacOS Sonoma quantization
-    for (volatile int i = 1; i < n; ++i) {
++#if defined(__APPLE__) && defined(__clang_major__) && __clang_major__ >= 15
++    // use 'volatile' to prevent unroll and work around a bug in Apple clang 15.x.x
++    for (volatile int i = 1; i < n; ++i) {
++#else
+     for (int i = 1; i < n; ++i) {
++#endif
         if (x[i] < min) min = x[i];
         if (x[i] > max) max = x[i];
         float w = weights[i];