diff --git a/libavcodec/nellymoser.c b/libavcodec/nellymoser.c
index 0740c75a0f..d6d5b7a910 100644
--- a/libavcodec/nellymoser.c
+++ b/libavcodec/nellymoser.c
@@ -85,7 +85,7 @@ const int16_t ff_nelly_delta_table[32] = {
 
 static inline int signed_shift(int i, int shift) {
     if (shift > 0)
-        return i << shift;
+        return (unsigned)i << shift;
     return i >> -shift;
 }
 
@@ -109,7 +109,7 @@ static int headroom(int *la)
         return 31;
     }
     l = 30 - av_log2(FFABS(*la));
-    *la <<= l;
+    *la *= 1<<l;
     return l;
 }