diff --git a/src/aal/aal.h b/src/aal/aal.h
index 4f5355f..1fb58b7 100644
--- a/src/aal/aal.h
+++ b/src/aal/aal.h
@@ -77,12 +77,15 @@ namespace snmalloc
             tick.time_since_epoch())
             .count());
       }
+      else
+      {
 #if __has_builtin(__builtin_readcyclecounter) && \
   !defined(SNMALLOC_NO_AAL_BUILTINS)
-      return __builtin_readcyclecounter();
+        return __builtin_readcyclecounter();
 #else
-      return Arch::tick();
+        return Arch::tick();
 #endif
+      }
     }
   };
 
diff --git a/src/aal/aal_arm.h b/src/aal/aal_arm.h
index 9dc722b..1bdc053 100644
--- a/src/aal/aal_arm.h
+++ b/src/aal/aal_arm.h
@@ -1,6 +1,6 @@
 #pragma once
 
-#if defined(__arch64__)
+#if defined(__aarch64__)
 #  define SNMALLOC_VA_BITS_64
 #else
 #  define SNMALLOC_VA_BITS_32
diff --git a/src/pal/pal_posix.h b/src/pal/pal_posix.h
index 4c3a842..e15a63f 100644
--- a/src/pal/pal_posix.h
+++ b/src/pal/pal_posix.h
@@ -76,15 +76,15 @@ namespace snmalloc
       SNMALLOC_ASSERT(
         is_aligned_block<OS_PAGE_SIZE>(p, size) || (zero_mem == NoZero));
 
-      if constexpr (zero_mem == YesZero)
-        static_cast<OS*>(this)->template zero<true>(p, size);
-
 #ifdef USE_POSIX_COMMIT_CHECKS
       mprotect(p, size, PROT_READ | PROT_WRITE);
 #else
       UNUSED(p);
       UNUSED(size);
 #endif
+
+      if constexpr (zero_mem == YesZero)
+        static_cast<OS*>(this)->template zero<true>(p, size);
     }
 
     /**