diff --git a/lib/copy-sync/copy-sync.js b/lib/copy-sync/copy-sync.js
index d1e821d1..a0265104 100644
--- a/lib/copy-sync/copy-sync.js
+++ b/lib/copy-sync/copy-sync.js
@@ -65,6 +65,9 @@ function mayCopyFile (srcStat, src, dest, opts) {
   }
 }
 
+let copyFileUsed = false
+let copyFileFallbackUsed = false
+
 function copyFile (srcStat, src, dest, opts) {
   if (typeof fs.copyFileSync === 'function') {
     fs.copyFileSync(src, dest)
@@ -74,8 +77,10 @@ function copyFile (srcStat, src, dest, opts) {
       // (through utimes call)
       fs.chmodSync(dest, srcStat.mode | 0o200)
     }
+    if (!copyFileUsed) { copyFileUsed = true; console.log('copyFile used (sync)') }
     return setDestTimestampsAndMode(srcStat, src, dest, opts)
   }
+  if (!copyFileFallbackUsed) { copyFileFallbackUsed = true; console.log('copyFileFallback used (sync)') }
   return copyFileFallback(srcStat, src, dest, opts)
 }
 
diff --git a/lib/copy/copy.js b/lib/copy/copy.js
index 373d06d0..c03eb600 100644
--- a/lib/copy/copy.js
+++ b/lib/copy/copy.js
@@ -93,6 +93,9 @@ function mayCopyFile (srcStat, src, dest, opts, cb) {
   } else return cb()
 }
 
+let copyFileUsed = false
+let copyFileFallbackUsed = false
+
 function copyFile (srcStat, src, dest, opts, cb) {
   if (typeof fs.copyFile === 'function') {
     return fs.copyFile(src, dest, err => {
@@ -106,9 +109,11 @@ function copyFile (srcStat, src, dest, opts, cb) {
           return setDestTimestampsAndMode(srcStat, src, dest, opts, cb)
         })
       }
+      if (!copyFileUsed) { copyFileUsed = true; console.log('copyFile used') }
       return setDestTimestampsAndMode(srcStat, src, dest, opts, cb)
     })
   }
+  if (!copyFileFallbackUsed) { copyFileFallbackUsed = true; console.log('copyFileFallback used') }
   return copyFileFallback(srcStat, src, dest, opts, cb)
 }