[Fortran, PR20897] Disallow intrinsic type names as derived type names

[Tobias Schlüter <tobias dot schlueter at physik dot uni-muenchen dot de>]

Hi,

this is a very simple fix for this old bug.  The patch is self-explaining.

Built and tested on i386-darwin.  Ok?

- Tobi

2007-03-22  Tobias Schlüter  <tobi@gcc.gnu.org>

	PR fortran/20897
fortran/
	* decl.c (gfc_match_derived_decl): Reliably reject
	'doubleprecision' and 'doublecomplex' as type names.
testsuite/
	* gfortran.dg/derived_name_1.f90: New.
	* gfortran.dg/derived_name_2.f: New.

Index: fortran/decl.c
===================================================================
--- fortran/decl.c	(revision 123109)
+++ fortran/decl.c	(working copy)
@@ -4341,12 +4341,16 @@ loop:
     return m;
 
   /* Make sure the name isn't the name of an intrinsic type.  The
-     'double precision' type doesn't get past the name matcher.  */
+     'double {precision,complex}' types don't get past the name
+     matcher, unless they're written as a single word or in fixed
+     form.  */
   if (strcmp (name, "integer") == 0
       || strcmp (name, "real") == 0
       || strcmp (name, "character") == 0
       || strcmp (name, "logical") == 0
-      || strcmp (name, "complex") == 0)
+      || strcmp (name, "complex") == 0
+      || strcmp (name, "doubleprecision") == 0
+      || strcmp (name, "doublecomplex") == 0)
     {
       gfc_error ("Type name '%s' at %C cannot be the same as an intrinsic "
 		 "type", name);
Index: testsuite/gfortran.dg/derived_name_1.f90
===================================================================
--- testsuite/gfortran.dg/derived_name_1.f90	(revision 0)
+++ testsuite/gfortran.dg/derived_name_1.f90	(revision 0)
@@ -0,0 +1,19 @@
+! { dg-do compile }
+! PR 20897
+! Make sure intrinsic type names do not appear as names of derived types
+type integer ! { dg-error "cannot be the same as an intrinsic type" }
+type real    ! { dg-error "cannot be the same as an intrinsic type" }
+type complex ! { dg-error "cannot be the same as an intrinsic type" }
+type character ! { dg-error "cannot be the same as an intrinsic type" }
+type logical ! { dg-error "cannot be the same as an intrinsic type" }
+type complex ! { dg-error "cannot be the same as an intrinsic type" }
+type double precision ! { dg-error "Unclassifiable statement" }
+type doubleprecision ! { dg-error "cannot be the same as an intrinsic type" }
+type double complex ! { dg-error "Unclassifiable statement" }
+type doublecomplex ! { dg-error "cannot be the same as an intrinsic type" }
+
+type x
+   integer y
+end type x
+end
+
Index: testsuite/gfortran.dg/derived_name_2.f
===================================================================
--- testsuite/gfortran.dg/derived_name_2.f	(revision 0)
+++ testsuite/gfortran.dg/derived_name_2.f	(revision 0)
@@ -0,0 +1,19 @@
+! { dg-do compile }
+! PR 20897
+! Make sure intrinsic type names do not appear as names of derived types
+      type integer     ! { dg-error "cannot be the same as an intrinsic type" }
+      type real        ! { dg-error "cannot be the same as an intrinsic type" }
+      type complex     ! { dg-error "cannot be the same as an intrinsic type" }
+      type character   ! { dg-error "cannot be the same as an intrinsic type" }
+      type logical     ! { dg-error "cannot be the same as an intrinsic type" }
+      type complex     ! { dg-error "cannot be the same as an intrinsic type" }
+      type double precision     ! { dg-error "cannot be the same as an intrinsic type" }
+      type doubleprecision      ! { dg-error "cannot be the same as an intrinsic type" }
+      type double complex       ! { dg-error "cannot be the same as an intrinsic type" }
+      type doublecomplex        ! { dg-error "cannot be the same as an intrinsic type" }
+
+      type x
+      integer y
+      end type x
+      end
+