ice in gfc_insert_bbt

[François-Xavier Coudert]

> Please note that somewhere between revisions 121818 and current HEAD,
> an ICE was introduced in f951 (x86_64).

Only two patches to the front-end might have introduced this regression:

2007-02-11  Tobias Schlüter  <tobi@gcc.gnu.org>

	PR fortran/30478
	* decl.c (add_init_expr_to_sym): Remove ENUM specific code.
	(variable_decl): Likewise.  Rewrap comment.
	(match_attr_spec): Remove ENUM specific code.
	(gfc_match_enum): Fix typo in error message.
	(enumerator_decl): New function.
	(gfc_match_enumerator_def): Use enumerator_decl instead of
	variable_decl.  Adapt code accordingly.

2007-02-11  Paul Thomas  <pault@gcc.gnu.org>

	PR fortran/30554
	* module.c (find_symtree_for_symbol): New function to return
	a symtree that is not a "unique symtree" given a symbol.
	(read_module): Do not automatically set pointer_info to
	referenced because this inhibits the generation of a unique
	symtree.  Recycle the existing symtree if possible by calling
	find_symtree_for_symbol.

	PR fortran/30319
	* decl.c (add_init_expr_to_sym): Make new charlen for an array
	constructor initializer.


Seeing your backtrace, I think it's Paul's patch. Could you confirm
that the code that gives the ICE doesn't use ENUMERATORs?

FX