diff --git a/src/libstore/gc.cc b/src/libstore/gc.cc
index 366dbfb0..f7360167 100644
--- a/src/libstore/gc.cc
+++ b/src/libstore/gc.cc
@@ -920,11 +920,11 @@ void LocalStore::autoGC(bool sync)
                     promise.set_value();
                 });
 
-                printInfo("running auto-GC to free %d bytes", settings.maxFree - avail);
-
                 GCOptions options;
                 options.maxFreed = settings.maxFree - avail;
 
+                printInfo("running auto-GC to free %d bytes", options.maxFreed);
+
                 GCResults results;
 
                 collectGarbage(options, results);