[C++ PATCH]: fix bug 262 ICE

[Nathan Sidwell <nathan at codesourcery dot com>]

Hi,
I've installed the attached patch and tests which fix bug 262
That report turned out to be user error, but we ICE before
telling so.

handle_class_head pushes the scope within which the decl it locates
resides. later on we pop the scope of the type to  which that decl
refers to. If that decl is a typedef within one scope to a type in
another scope, we go bang! The common error is to write something like
        class X::X
here X::X is the implicit typedef of ::X within its own scope. So we
push ::X as a scope, but pop ::.

Approved by Mark, built & tested on i686-pc-linux-gnu

nathan
-- 
Dr Nathan Sidwell   ::   http://www.codesourcery.com   ::   CodeSourcery LLC
         'But that's a lie.' - 'Yes it is. What's your point?'
nathan@codesourcery.com : http://www.cs.bris.ac.uk/~nathan/ : nathan@acm.org
2000-06-23  Nathan Sidwell  <nathan@codesourcery.com>

	* decl2.c (handle_class_head): Bash typedefs to the type's main
	decl.

Index: cp/decl2.c
===================================================================
RCS file: /cvs/gcc/egcs/gcc/cp/decl2.c,v
retrieving revision 1.370
diff -c -3 -p -r1.370 decl2.c
*** decl2.c	2000/06/23 01:14:39	1.370
--- decl2.c	2000/06/23 10:27:08
*************** handle_class_head (aggr, scope, id)
*** 5362,5368 ****
    tree decl;
  
    if (TREE_CODE (id) == TYPE_DECL)
!     decl = id;
    else if (DECL_CLASS_TEMPLATE_P (id))
      decl = DECL_TEMPLATE_RESULT (id);
    else 
--- 5362,5370 ----
    tree decl;
  
    if (TREE_CODE (id) == TYPE_DECL)
!     /* We must bash typedefs back to the main decl of the type. Otherwise
!        we become confused about scopes.  */
!     decl = TYPE_MAIN_DECL (TREE_TYPE (id));
    else if (DECL_CLASS_TEMPLATE_P (id))
      decl = DECL_TEMPLATE_RESULT (id);
    else 
2000-06-26  Nathan Sidwell  <nathan@codesourcery.com>

	* g++.old-deja/g++.pt/syntax1.C: New test.
	* g++.old-deja/g++.pt/syntax2.C: New test.
	* g++.old-deja/g++.other/syntax3.C: New test.
	* g++.old-deja/g++.other/syntax4.C: New test.

Index: testsuite/g++.old-deja/g++.other/syntax3.C
===================================================================
RCS file: syntax3.C
diff -N syntax3.C
*** /dev/null	Tue May  5 13:32:27 1998
--- syntax3.C	Mon Jun 26 03:58:47 2000
***************
*** 0 ****
--- 1,21 ----
+ // Build don't link:
+ 
+ // Copyright (C) 2000 Free Software Foundation, Inc.
+ // Contributed by Nathan Sidwell 22 June 2000 <nathan@codesourcery.com>
+ 
+ // Origin GNATS bug report 262 from Jeremy Sanders <jss@ast.cam.ac.uk>
+ // and several others. With templates, it's very easy to say something
+ // erroneous like
+ //    template class X::X<whatever>
+ // The culprit
+ //    ... class X::X ...
+ // caused us to ICE as we got confused about pushing and popping scopes.
+ 
+ class X
+ {
+   public:
+   X();
+ };
+ 
+ class X::X () {}    // ERROR - parse error
+ X::X () {}
Index: testsuite/g++.old-deja/g++.other/syntax4.C
===================================================================
RCS file: syntax4.C
diff -N syntax4.C
*** /dev/null	Tue May  5 13:32:27 1998
--- syntax4.C	Mon Jun 26 03:58:47 2000
***************
*** 0 ****
--- 1,26 ----
+ // Build don't link:
+ 
+ // Copyright (C) 2000 Free Software Foundation, Inc.
+ // Contributed by Nathan Sidwell 22 June 2000 <nathan@codesourcery.com>
+ 
+ // Origin GNATS bug report 262 from Jeremy Sanders <jss@ast.cam.ac.uk>
+ // and several others. With templates, it's very easy to say something
+ // erroneous like
+ //    template class X::X<whatever>
+ // The culprit
+ //    ... class X::X ...
+ // caused us to ICE as we got confused about pushing and popping scopes.
+ 
+ class X {
+   X ();
+ };
+ 
+ class Y {
+   public:
+   typedef ::X W;
+   class Z;
+ };
+ 
+ class Y::Z {};
+ class Y::W  () {}  // ERROR - parse error
+ Y::W::X () {}
Index: testsuite/g++.old-deja/g++.pt/syntax1.C
===================================================================
RCS file: syntax1.C
diff -N syntax1.C
*** /dev/null	Tue May  5 13:32:27 1998
--- syntax1.C	Mon Jun 26 03:58:47 2000
***************
*** 0 ****
--- 1,26 ----
+ // Build don't link:
+ 
+ // Copyright (C) 2000 Free Software Foundation, Inc.
+ // Contributed by Nathan Sidwell 22 June 2000 <nathan@codesourcery.com>
+ 
+ // Origin GNATS bug report 262 from Jeremy Sanders <jss@ast.cam.ac.uk>
+ // and several others. With templates, it's very easy to say something
+ // erroneous like
+ //    template class X::X<whatever>
+ // The culprit
+ //    ... class X::X ...
+ // caused us to ICE as we got confused about pushing and popping scopes.
+ 
+ 
+ 
+ class Y
+ {
+   public:
+   template <class T> Y(T &);
+ };
+ template <class T> Y::Y(T &) {}
+ 
+ template class Y::Y (int);  // ERROR - parse error
+ template Y::Y (int);        // ERROR - template-id does not match
+ template Y::Y (int &);
+ 
Index: testsuite/g++.old-deja/g++.pt/syntax2.C
===================================================================
RCS file: syntax2.C
diff -N syntax2.C
*** /dev/null	Tue May  5 13:32:27 1998
--- syntax2.C	Mon Jun 26 03:58:47 2000
***************
*** 0 ****
--- 1,27 ----
+ // Build don't link:
+ 
+ // Copyright (C) 2000 Free Software Foundation, Inc.
+ // Contributed by Nathan Sidwell 22 June 2000 <nathan@codesourcery.com>
+ 
+ // Origin GNATS bug report 262 from Jeremy Sanders <jss@ast.cam.ac.uk>
+ // and several others. With templates, it's very easy to say something
+ // erroneous like
+ //    template class X::X<whatever>
+ // The culprit
+ //    ... class X::X ...
+ // caused us to ICE as we got confused about pushing and popping scopes.
+ 
+ template <class T> class image
+ {
+ public:   
+   template <class U> image(const image<U> &copy);
+ };
+ 
+ template <class T> template <class U> image<T>::image(const image<U> &copy)
+ {
+ }
+ 
+ template class image<double>;
+ template class image<double>::image (const image<int> &); // ERROR - parse error
+ template class image<double>::image (image<int>); // ERROR - specified as declarator-id
+ template image<double>::image (const image<int> &);