PR fortran/97491 - Wrong restriction for VALUE arguments of pure procedures

A dummy argument with the VALUE attribute may be redefined in a PURE or
ELEMENTAL procedure.  Adjust the associated purity check.

gcc/fortran/ChangeLog:

	* resolve.c (gfc_impure_variable): A dummy argument with the VALUE
	attribute may be redefined without making a procedure impure.

gcc/testsuite/ChangeLog:

	* gfortran.dg/value_8.f90: New test.

gcc/fortran/resolve.c

@@ -16476,6 +16476,7 @@ gfc_impure_variable (gfc_symbol *sym)
 
   proc = sym->ns->proc_name;
   if (sym->attr.dummy
+      && !sym->attr.value
       && ((proc->attr.subroutine && sym->attr.intent == INTENT_IN)
 	  || proc->attr.function))
     return 1;

gcc/testsuite/gfortran.dg/value_8.f90

@@ -0,0 +1,16 @@
+! { dg-do compile }
+! PR97491 - Wrong restriction for VALUE arguments of pure procedures
+
+pure function foo (x) result (ret)
+  integer        :: ret
+  integer, value :: x
+  x = x / 2
+  ret = x
+end function foo
+
+elemental function foo1 (x)
+  integer        :: foo1
+  integer, value :: x
+  x = x / 2
+  foo1 = x
+end function foo1