[gcc r9-9749] Fortran - ensure simplification of bounds of array-valued named constants

[gcc r9-9749] Fortran - ensure simplification of bounds of array-valued named constants

[Harald Anlauf]

https://gcc.gnu.org/g:3a70195d7da49fe793ce3eb0e839b9ceea96c97a

commit r9-9749-g3a70195d7da49fe793ce3eb0e839b9ceea96c97a
Author: Harald Anlauf <anlauf@gmx.de>
Date:   Mon Sep 13 19:28:10 2021 +0200

    Fortran - ensure simplification of bounds of array-valued named constants
    
    gcc/fortran/ChangeLog:
    
            PR fortran/82314
            * decl.c (add_init_expr_to_sym): For proper initialization of
            array-valued named constants the array bounds need to be
            simplified before adding the initializer.
    
    gcc/testsuite/ChangeLog:
    
            PR fortran/82314
            * gfortran.dg/pr82314.f90: New test.
    
    (cherry picked from commit 104c05c5284b7822d770ee51a7d91946c7e56d50)

Diff:
---
 gcc/fortran/decl.c                    | 18 ++++++++++++++++++
 gcc/testsuite/gfortran.dg/pr82314.f90 | 11 +++++++++++
 2 files changed, 29 insertions(+)

diff --git a/gcc/fortran/decl.c b/gcc/fortran/decl.c
index 00321da827e..51238e49fb1 100644
--- a/gcc/fortran/decl.c
+++ b/gcc/fortran/decl.c
@@ -2043,6 +2043,24 @@ add_init_expr_to_sym (const char *name, gfc_expr **initp, locus *var_locus)
 	  sym->as->type = AS_EXPLICIT;
 	}
 
+      /* Ensure that explicit bounds are simplified.  */
+      if (sym->attr.flavor == FL_PARAMETER && sym->attr.dimension
+	  && sym->as->type == AS_EXPLICIT)
+	{
+	  for (int dim = 0; dim < sym->as->rank; ++dim)
+	    {
+	      gfc_expr *e;
+
+	      e = sym->as->lower[dim];
+	      if (e->expr_type != EXPR_CONSTANT)
+		gfc_reduce_init_expr (e);
+
+	      e = sym->as->upper[dim];
+	      if (e->expr_type != EXPR_CONSTANT)
+		gfc_reduce_init_expr (e);
+	    }
+	}
+
       /* Need to check if the expression we initialized this
 	 to was one of the iso_c_binding named constants.  If so,
 	 and we're a parameter (constant), let it be iso_c.
diff --git a/gcc/testsuite/gfortran.dg/pr82314.f90 b/gcc/testsuite/gfortran.dg/pr82314.f90
new file mode 100644
index 00000000000..3a147e22711
--- /dev/null
+++ b/gcc/testsuite/gfortran.dg/pr82314.f90
@@ -0,0 +1,11 @@
+! { dg-do run }
+! PR fortran/82314 - ICE in gfc_conv_expr_descriptor
+
+program p
+  implicit none
+  integer, parameter :: karray(merge(3,7,.true.):merge(3,7,.false.)) = 1
+  integer, parameter :: i = size   (karray)
+  integer, parameter :: l = lbound (karray,1)
+  integer, parameter :: u = ubound (karray,1)
+  if (l /= 3 .or. u /= 7 .or. i /= 5) stop 1
+end