diff --git a/driver/level2/trmv_thread.c b/driver/level2/trmv_thread.c
index 43eeb40d2..2cc6d8726 100644
--- a/driver/level2/trmv_thread.c
+++ b/driver/level2/trmv_thread.c
@@ -273,9 +273,17 @@ static int trmv_kernel(blas_arg_t *args, BLASLONG *range_m, BLASLONG *range_n, F
 }
 
 #ifndef COMPLEX
-int CNAME(BLASLONG m, FLOAT *a, BLASLONG lda, FLOAT *x, BLASLONG incx, FLOAT *buffer, int nthreads){
+int
+#ifndef C_MSVC
+__attribute__((visibility("hidden")))
+#endif
+	CNAME(BLASLONG m, FLOAT *a, BLASLONG lda, FLOAT *x, BLASLONG incx, FLOAT *buffer, int nthreads){
 #else
-int CNAME(BLASLONG m, FLOAT *a, BLASLONG lda, FLOAT *x, BLASLONG incx, FLOAT *buffer, int nthreads){
+int
+#ifndef C_MSVC
+__attribute__((visibility("hidden")))
+#endif
+	CNAME(BLASLONG m, FLOAT *a, BLASLONG lda, FLOAT *x, BLASLONG incx, FLOAT *buffer, int nthreads){
 #endif
 
   blas_arg_t args;