diff --git a/kernel/x86_64/zgemv_t_4.c b/kernel/x86_64/zgemv_t_4.c
index f5e5572f9..c4a38202b 100644
--- a/kernel/x86_64/zgemv_t_4.c
+++ b/kernel/x86_64/zgemv_t_4.c
@@ -313,7 +313,7 @@ int CNAME(BLASLONG m, BLASLONG n, BLASLONG dummy1, FLOAT alpha_r, FLOAT alpha_i,
 
 			for( i = 0; i < n1 ; i++)
 			{
-				memset(ybuffer,0,sizeoff(ybuffer));
+				memset(ybuffer,0,sizeof(ybuffer));
 				zgemv_kernel_4x4(NB,ap,xbuffer,ybuffer,alpha);
 				ap[0] += lda4;
 				ap[1] += lda4;