diff --git a/tests/tcg/i386/test-avx.c b/tests/tcg/i386/test-avx.c
index 230e6d84b8..80fe363cfc 100644
--- a/tests/tcg/i386/test-avx.c
+++ b/tests/tcg/i386/test-avx.c
@@ -244,7 +244,7 @@ v4di indexd = {0x00000002ffffffcdull, 0xfffffff500000010ull,
                0x0000003afffffff0ull, 0x000000000000000eull};
 
 v4di gather_mem[0x20];
-_Static_assert(sizeof(gather_mem) == 1024);
+_Static_assert(sizeof(gather_mem) == 1024, "gather_mem not expected size");
 
 void init_f16reg(v4di *r)
 {