--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gcc/testsuite/gfortran.dg/warn_conversion.f90	Fri Oct 27 22:46:09 2017 +0900
@@ -0,0 +1,61 @@
+! { dg-do compile }
+! { dg-options "-Wconversion" }
+
+!
+! PR fortran/27866 -improve -Wconversion
+!
+SUBROUTINE pr27866
+  double precision :: d
+  real   :: r
+  d = 4d99
+  r = d                 ! { dg-warning "conversion" }
+END SUBROUTINE
+
+SUBROUTINE pr27866c4
+  real(kind=4)    :: a
+  real(kind=8)    :: b
+  integer(kind=1) :: i1
+  integer(kind=4) :: i4
+  i4 = 2.3              ! { dg-warning "conversion" }
+  i1 = 500              ! { dg-error "overflow" }
+  a = 2**26-1           ! { dg-warning "Change of value in conversion" }
+  b = 1d999             ! { dg-error "overflow" }
+
+  a = i4                ! assignment INTEGER(4) to REAL(4) - no warning
+  b = i4                ! assignment INTEGER(4) to REAL(8) - no warning
+  i1 = i4               ! { dg-warning "conversion" }
+  a = b                 ! { dg-warning "conversion" }
+END SUBROUTINE
+
+
+!
+! PR fortran/35003 - spurious warning with -Wconversion
+! Contributed by Brian Barnes <bcbarnes AT gmail DOT com>
+!
+SUBROUTINE pr35003
+  IMPLICIT NONE
+  integer(8) :: i, n
+  n = 1_8
+
+  do i = 1_8,n
+  enddo
+END SUBROUTINE
+
+
+!
+! PR fortran/42809 - Too much noise with -Wconversion
+! Contributed by Harald Anlauf <anlauf AT gmx DOT de>
+!
+SUBROUTINE pr42809
+  implicit none
+  integer, parameter :: sp = kind (1.0)
+  integer, parameter :: dp = kind (1.d0)
+  real(sp)     :: s
+  real(dp)     :: d
+  complex(dp)  :: z
+
+  s = 0                 ! assignment INTEGER(4) to REAL(4) - no warning
+  d = s                 ! assignment REAL((8)) to REAL(4) - no warning
+  z = (0, 1)            ! conversion INTEGER(4) to REAL(4),
+                        ! assignment COMPLEX(4) to COMPLEX(8) - no warning
+END SUBROUTINE