diff --git a/cpp_thread_test/test_dgemm_f90.f b/cpp_thread_test/test_dgemm_f90.f
index 8b1378917..9a34c7b1b 100644
--- a/cpp_thread_test/test_dgemm_f90.f
+++ b/cpp_thread_test/test_dgemm_f90.f
@@ -1 +1,23 @@
+    SUBROUTINE tester(i)
+    REAL_8, DIMENSION(:), ALLOCATABLE :: A,B,C
+    REAL_8 :: rnd(3)
+    INTEGER :: i
+    INTEGER :: M,N,K
+    ! test random sizes
+    CALL RANDOM_NUMBER(rnd)
+    M=rnd(1)_37+1 ; N=rnd(2)_37+1 ; K=rnd(3)_37+1
+    ALLOCATE(C(M_N),A(M_K),B(K_N))
+    A=0 ; B=0 ; C=0
+    CALL DGEMM("N","N",M,N,K,1.0D0,A,M,B,K,0.0D0,C,M)
+    CALL DGEMM("T","N",M,N,K,1.0D0,A,K,B,K,0.0D0,C,M)
+    CALL DGEMM("N","T",M,N,K,1.0D0,A,M,B,N,0.0D0,C,M)
+    CALL DGEMM("T","T",M,N,K,1.0D0,A,K,B,N,0.0D0,C,M)
+    END SUBROUTINE tester
+
+PROGRAM TEST_THREAD_SAFE
+!$OMP PARALLEL DO
+DO i=1,30
+CALL tester(i)
+ENDDO
+END PROGRAM