diff --git a/libc/bionic/libc_init_static.cpp b/libc/bionic/libc_init_static.cpp
index 66aaeaa9b..36c61e876 100644
--- a/libc/bionic/libc_init_static.cpp
+++ b/libc/bionic/libc_init_static.cpp
@@ -224,17 +224,14 @@ static bool get_environment_memtag_setting(HeapTaggingLevel* level) {
 
   const char* basename = __gnu_basename(progname);
 
-  static constexpr size_t kOptionsSize = PROP_VALUE_MAX;
-  char options_str[kOptionsSize];
-  size_t sysprop_size = strlen(basename) + strlen(kMemtagPrognameSyspropPrefix) + 1;
-  char* sysprop_name = static_cast<char*>(alloca(sysprop_size));
-
-  async_safe_format_buffer(sysprop_name, sysprop_size, "%s%s", kMemtagPrognameSyspropPrefix,
+  char options_str[PROP_VALUE_MAX];
+  char sysprop_name[512];
+  async_safe_format_buffer(sysprop_name, sizeof(sysprop_name), "%s%s", kMemtagPrognameSyspropPrefix,
                            basename);
   const char* sys_prop_names[] = {sysprop_name, kMemtagGlobalSysprop};
 
   if (!get_config_from_env_or_sysprops("MEMTAG_OPTIONS", sys_prop_names, arraysize(sys_prop_names),
-                                       options_str, kOptionsSize)) {
+                                       options_str, sizeof(options_str))) {
     return false;
   }