+
−! { dg-do compile }
+
−! { dg-options "-ffrontend-optimize -fdump-tree-original" }
+
−! PR fortran/52537 - optimize comparisons with empty strings
+
−program main
+
−  implicit none
+
−  character(len=10) :: a
+
−  character(len=30) :: line
+
−  character(len=4,kind=4) :: c4
+
−  line = 'x'
+
−  read (unit=line,fmt='(A)') a
+
−  c4 = 4_'foo'
+
−  if (c4 == 4_' ') print *,"foobar"
+
−  if (trim(a) == '') print *,"empty"
+
−  call foo(a)
+
−  if (trim(a) == '    ') print *,"empty"
+
−contains
+
−  subroutine foo(b)
+
−    character(*) :: b
+
−    if (b /= '   ') print *,"full"
+
−  end subroutine foo
+
−end program main
+
−! { dg-final { scan-tree-dump-times "_gfortran_string_len_trim" 4 "original" } }