diff --git a/src/common/mipmap_cache.c b/src/common/mipmap_cache.c
index 741598d3c6b4..58a360f4bb53 100644
--- a/src/common/mipmap_cache.c
+++ b/src/common/mipmap_cache.c
@@ -461,7 +461,7 @@ void dt_mipmap_cache_init(dt_mipmap_cache_t *cache)
   // we want at least 100MB, and consider 8G just still reasonable.
   int64_t cache_memory = dt_conf_get_int64("cache_memory");
   int worker_threads = dt_conf_get_int("worker_threads");
-  size_t max_mem = CLAMPS(cache_memory, 100u << 20, ((uint64_t)8) << 30);
+  size_t max_mem = CLAMPS(cache_memory, 100u << 20, ((size_t)8) << 30);
   const uint32_t parallel = CLAMP(worker_threads, 1, 8);
 
   // Fixed sizes for the thumbnail mip levels, selected for coverage of most screen sizes