[gcc r11-9213] Fortran: handle initialization of derived type parameter arrays from scalar

[gcc r11-9213] Fortran: handle initialization of derived type parameter arrays from scalar

[Harald Anlauf]

https://gcc.gnu.org/g:1b740d8000cac8048c728fb0bd75c71464eeee29

commit r11-9213-g1b740d8000cac8048c728fb0bd75c71464eeee29
Author: Harald Anlauf <anlauf@gmx.de>
Date:   Sun Oct 10 20:11:43 2021 +0200

    Fortran: handle initialization of derived type parameter arrays from scalar
    
    gcc/fortran/ChangeLog:
    
            PR fortran/99348
            PR fortran/102521
            * decl.c (add_init_expr_to_sym): Extend initialization of
            parameter arrays from scalars to handle derived types.
    
    gcc/testsuite/ChangeLog:
    
            PR fortran/99348
            PR fortran/102521
            * gfortran.dg/parameter_array_init_8.f90: New test.
    
    (cherry picked from commit 74ccca380cde5e79e082d39214b306a90ded0344)

Diff:
---
 gcc/fortran/decl.c                                 | 10 ++++++---
 .../gfortran.dg/parameter_array_init_8.f90         | 25 ++++++++++++++++++++++
 2 files changed, 32 insertions(+), 3 deletions(-)

diff --git a/gcc/fortran/decl.c b/gcc/fortran/decl.c
index 4606155f699..982e3e9d9ac 100644
--- a/gcc/fortran/decl.c
+++ b/gcc/fortran/decl.c
@@ -2126,12 +2126,16 @@ add_init_expr_to_sym (const char *name, gfc_expr **initp, locus *var_locus)
 	  gfc_expr *array;
 	  int n;
 	  if (sym->attr.flavor == FL_PARAMETER
-		&& init->expr_type == EXPR_CONSTANT
-		&& spec_size (sym->as, &size)
-		&& mpz_cmp_si (size, 0) > 0)
+	      && gfc_is_constant_expr (init)
+	      && (init->expr_type == EXPR_CONSTANT
+		  || init->expr_type == EXPR_STRUCTURE)
+	      && spec_size (sym->as, &size)
+	      && mpz_cmp_si (size, 0) > 0)
 	    {
 	      array = gfc_get_array_expr (init->ts.type, init->ts.kind,
 					  &init->where);
+	      if (init->ts.type == BT_DERIVED)
+		array->ts.u.derived = init->ts.u.derived;
 	      for (n = 0; n < (int)mpz_get_si (size); n++)
 		gfc_constructor_append_expr (&array->value.constructor,
 					     n == 0
diff --git a/gcc/testsuite/gfortran.dg/parameter_array_init_8.f90 b/gcc/testsuite/gfortran.dg/parameter_array_init_8.f90
new file mode 100644
index 00000000000..2e5f7694d3a
--- /dev/null
+++ b/gcc/testsuite/gfortran.dg/parameter_array_init_8.f90
@@ -0,0 +1,25 @@
+! { dg-do run }
+! PR fortran/99348
+! PR fortran/102521
+! Check simplifications for initialization of DT parameter arrays
+
+program p
+  type t
+     integer :: n
+  end type
+  type(t), parameter :: a(4)   = t(1)
+  type(t), parameter :: d(*)   = a
+  type(t), parameter :: b(2,2) = reshape(d, [2,2])
+  integer, parameter :: nn     = b(2,2)% n
+  type u
+     character(3) :: c
+  end type
+  type(u),      parameter :: x(2,3) = u('ab')
+  type(u),      parameter :: y(*,*) = transpose (x)
+  character(*), parameter :: c      = y(3,2)% c
+  integer,      parameter :: lc     = c% len
+  integer,      parameter :: lyc    = len (y(3,2)% c)
+! integer,      parameter :: lxc    = x(1,1)% c% len    ! fails (pr101735?)
+  if (nn /= 1) stop 1
+  if (lc /= 3 .or. lyc /= 3 .or. c /= "ab ") stop 2
+end