1 files changed, 22 insertions, 0 deletions
diff --git a/gcc/testsuite/gfortran.dg/do_check_3.f90 b/gcc/testsuite/gfortran.dg/do_check_3.f90
new file mode 100644
index 000000000..15086c20a
--- /dev/null
+++ b/gcc/testsuite/gfortran.dg/do_check_3.f90
@@ -0,0 +1,22 @@
+! { dg-do run }
+! { dg-options "-fcheck=do" }
+! { dg-shouldfail "DO check" }
+!
+! PR fortran/34656
+! Run-time check for modifing loop variables
+!
+program test
+  implicit none
+  real :: i, j, k
+  j = 10.0
+  k = 1.0
+  do i = 1.0, j, k ! { dg-warning "must be integer" }
+    call modLoopVar(i)
+  end do
+contains
+  subroutine modLoopVar(x)
+    real :: x
+    x = x + 1
+  end subroutine modLoopVar
+end program test
+! { dg-output "Fortran runtime error: Loop variable has been modified" }