diff --git a/kitty/simd-string-impl.h b/kitty/simd-string-impl.h
index 0cb1d431e..12fde57d2 100644
--- a/kitty/simd-string-impl.h
+++ b/kitty/simd-string-impl.h
@@ -24,6 +24,7 @@ _Pragma("clang diagnostic pop")
 #define FUNC(name) CONCAT_EXPAND(name##_, BITS)
 #define integer_t CONCAT_EXPAND(CONCAT_EXPAND(simde__m, BITS), i)
 #define shift_right_by_bytes128 simde_mm_srli_si128
+#define count_trailing_zeros __builtin_ctz
 
 #if BITS == 128
 #define set1_epi8 simde_mm_set1_epi8
@@ -68,7 +69,7 @@ FUNC(find_either_of_two_bytes)(const uint8_t *haystack, const size_t sz, const u
         const integer_t matches = or_si(a_cmp, b_cmp);
         const int mask = movemask_epi8(matches);
         if (mask != 0) {
-            size_t pos = __builtin_ctz(mask);
+            size_t pos = count_trailing_zeros(mask);
             const uint8_t *ans = haystack + pos;
             if (ans < limit) return ans;
         }
@@ -128,7 +129,7 @@ FUNC(utf8_decode_to_esc)(UTF8Decoder *d, const uint8_t *src, size_t src_sz) {
     const integer_t esc_cmp = cmpeq_epi8(vec, esc_vec);
     const int esc_test_mask = movemask_epi8(esc_cmp);
     bool sentinel_found = false;
-    const unsigned num_of_bytes_to_first_esc = __builtin_ctz(esc_test_mask);
+    const unsigned num_of_bytes_to_first_esc = count_trailing_zeros(esc_test_mask);
     if (num_of_bytes_to_first_esc < src_sz) {
         sentinel_found = true;
         d->num_consumed = num_of_bytes_to_first_esc + 1;  // esc is also consumed
@@ -136,7 +137,7 @@ FUNC(utf8_decode_to_esc)(UTF8Decoder *d, const uint8_t *src, size_t src_sz) {
     } else d->num_consumed = src_sz;
 
     const int ascii_test_mask = movemask_epi8(vec);
-    const unsigned num_of_bytes_to_first_non_ascii_byte = __builtin_ctz(ascii_test_mask);
+    const unsigned num_of_bytes_to_first_non_ascii_byte = count_trailing_zeros(ascii_test_mask);
 
     if (num_of_bytes_to_first_non_ascii_byte >= src_sz) {  // no bytes with high bit (0x80) set, so just plain ASCII
         FUNC(output_plain_ascii)(d, vec, src_sz);
diff --git a/kitty/simd-string.c b/kitty/simd-string.c
index c2e8b7a32..65c39055c 100644
--- a/kitty/simd-string.c
+++ b/kitty/simd-string.c
@@ -117,13 +117,14 @@ bool
 init_simd(void *x) {
     PyObject *module = (PyObject*)x;
     if (PyModule_AddFunctions(module, module_methods) != 0) return false;
+    __builtin_cpu_init();
 #define A(x, val) { Py_INCREF(Py_##val); if (0 != PyModule_AddObject(module, #x, Py_##val)) return false; }
 #ifdef __APPLE__
 #ifdef __arm64__
     // simde takes care of NEON on Apple Silicon
     has_sse4_2 = true; has_avx2 = true;
 #else
-    has_sse4_2 = __builtin_cpu_supports("sse4.2") != 0; has_avx2 = __builtin_cpu_supports("avx2");
+    has_sse4_2 = __builtin_cpu_supports("sse4.2") != 0; has_avx2 = __builtin_cpu_supports("avx2") != 0;
 #endif
 #else
 #ifdef __aarch64__
@@ -131,7 +132,7 @@ init_simd(void *x) {
     // basic AVX2 and SSE4.2 intrinsics, so hopefully they work on ARM
     has_sse4_2 = true; has_avx2 = true;
 #else
-    has_sse4_2 = __builtin_cpu_supports("sse4.2") != 0; has_avx2 = __builtin_cpu_supports("avx2");
+    has_sse4_2 = __builtin_cpu_supports("sse4.2") != 0; has_avx2 = __builtin_cpu_supports("avx2") != 0;
 #endif
 #endif
     if (has_avx2) {