--- dyld/dyld-960/cache-builder/kernel_collection_builder.cpp
+++ dyld/dyld-957/cache-builder/kernel_collection_builder.cpp
@@ -77,17 +77,12 @@
     void error(const char* format, ...) {
         va_list list;
         va_start(list, format);
-        char* buffer = nullptr;
-        vasprintf(&buffer, format, list);
+        Diagnostics diag;
+        diag.error(format, list);
         va_end(list);
 
-        if ( buffer == nullptr )
-            return;
-
-        errorStorage.push_back(buffer);
+        errorStorage.push_back(diag.errorMessage());
         errors.push_back(errorStorage.back().data());
-
-        free(buffer);
     }
 
     void retain(CFTypeRef v) {