re PR fortran/78392 (ICE in gfc_trans_auto_array_allocation, at fortran/trans-array.c:5979)

2016-12-12  Janus Weil  <janus@gcc.gnu.org>

	PR fortran/78392
	* expr.c (gfc_is_constant_expr): Specification functions are not
	compile-time constants. Update documentation (add reference to F08
	standard), add a FIXME.
	(external_spec_function): Add reference to F08 standard.
	* resolve.c (resolve_fl_variable): Ditto.

2016-12-12  Janus Weil  <janus@gcc.gnu.org>

	PR fortran/78392
	* gfortran.dg/constant_shape.f90: New test case.

From-SVN: r243580

5 files changed, 41 insertions, 25 deletions

diff --git a/gcc/fortran/ChangeLog b/gcc/fortran/ChangeLog
index 1597a89..7a47db2 100644
--- a/gcc/fortran/ChangeLog
+++ b/gcc/fortran/ChangeLog
@@ -1,3 +1,12 @@
+2016-12-12  Janus Weil  <janus@gcc.gnu.org>
+
+	PR fortran/78392
+	* expr.c (gfc_is_constant_expr): Specification functions are not
+	compile-time constants. Update documentation (add reference to F08
+	standard), add a FIXME.
+	(external_spec_function): Add reference to F08 standard.
+	* resolve.c (resolve_fl_variable): Ditto.
+
 2016-12-10  Thomas Koenig  <tkoenig@gcc.gnu.org>
 
 	PR fortran/78226
diff --git a/gcc/fortran/expr.c b/gcc/fortran/expr.c
index 3464a20..c4a6ae1 100644
--- a/gcc/fortran/expr.c
+++ b/gcc/fortran/expr.c
@@ -881,15 +881,15 @@ done:
 }
 
 
-/* Function to determine if an expression is constant or not.  This
-   function expects that the expression has already been simplified.  */
+/* Determine if an expression is constant in the sense of F08:7.1.12.
+ * This function expects that the expression has already been simplified.
+ * FIXME: Return a bool, not an int.  */
 
 int
 gfc_is_constant_expr (gfc_expr *e)
 {
   gfc_constructor *c;
   gfc_actual_arglist *arg;
-  gfc_symbol *sym;
 
   if (e == NULL)
     return 1;
@@ -918,25 +918,6 @@ gfc_is_constant_expr (gfc_expr *e)
 	      return 0;
 	}
 
-      /* Specification functions are constant.  */
-      /* F95, 7.1.6.2; F2003, 7.1.7  */
-      sym = NULL;
-      if (e->symtree)
-	sym = e->symtree->n.sym;
-      if (e->value.function.esym)
-	sym = e->value.function.esym;
-
-      if (sym
-	  && sym->attr.function
-	  && sym->attr.pure
-	  && !sym->attr.intrinsic
-	  && !sym->attr.recursive
-	  && sym->attr.proc != PROC_INTERNAL
-	  && sym->attr.proc != PROC_ST_FUNCTION
-	  && sym->attr.proc != PROC_UNKNOWN
-	  && gfc_sym_get_dummy_args (sym) == NULL)
-	return 1;
-
       if (e->value.function.isym
 	  && (e->value.function.isym->elemental
 	      || e->value.function.isym->pure
@@ -2739,7 +2720,8 @@ restricted_args (gfc_actual_arglist *a)
 /************* Restricted/specification expressions *************/
 
 
-/* Make sure a non-intrinsic function is a specification function.  */
+/* Make sure a non-intrinsic function is a specification function,
+ * see F08:7.1.11.5.  */
 
 static bool
 external_spec_function (gfc_expr *e)
diff --git a/gcc/fortran/resolve.c b/gcc/fortran/resolve.c
index c7d872c..ece4d75 100644
--- a/gcc/fortran/resolve.c
+++ b/gcc/fortran/resolve.c
@@ -11825,8 +11825,8 @@ resolve_fl_variable (gfc_symbol *sym, int mp_flag)
       && !sym->attr.pointer
       && is_non_constant_shape_array (sym))
     {
-      /* The shape of a main program or module array needs to be
-	 constant.  */
+      /* F08:C541. The shape of an array defined in a main program or module
+       * needs to be constant.  */
       gfc_error ("The module or main program array %qs at %L must "
 		 "have constant shape", sym->name, &sym->declared_at);
       specification_expr = saved_specification_expr;
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index d6657b5..d333de1 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2016-12-12  Janus Weil  <janus@gcc.gnu.org>
+
+	PR fortran/78392
+	* gfortran.dg/constant_shape.f90: New test case.
+
 2016-12-12  Marek Polacek  <polacek@redhat.com>
 
 	PR c++/78647
diff --git a/gcc/testsuite/gfortran.dg/constant_shape.f90 b/gcc/testsuite/gfortran.dg/constant_shape.f90
new file mode 100644
index 0000000..c2eaf82
--- /dev/null
+++ b/gcc/testsuite/gfortran.dg/constant_shape.f90
@@ -0,0 +1,20 @@
+! { dg-do compile }
+!
+! PR 78392: ICE in gfc_trans_auto_array_allocation, at fortran/trans-array.c:5979
+!
+! Contributed by Janus Weil <janus@gcc.gnu.org>
+
+module mytypes
+   implicit none
+ contains
+   pure integer function get_i ()
+     get_i = 13
+   end function
+end module
+
+program test
+  use mytypes
+  implicit none
+  integer, dimension(get_i()) :: x  ! { dg-error "must have constant shape" }
+  print *, size (x)
+end