gdb/

gdb/
	Fix crashes on dangling display expressions.
	* ada-lang.c (ada_operator_check): New function.
	(ada_exp_descriptor): Fill-in the field operator_check.
	* c-lang.c (exp_descriptor_c): Fill-in the field operator_check.
	* jv-lang.c (exp_descriptor_java): Likewise.
	* m2-lang.c (exp_descriptor_modula2): Likewise.
	* scm-lang.c (exp_descriptor_scm): Likewise.
	* parse.c (exp_descriptor_standard): Likewise.
	(operator_check_standard): New function.
	(exp_iterate, exp_uses_objfile_iter, exp_uses_objfile): New functions.
	* parser-defs.h (struct exp_descriptor): New field operator_check.
	(operator_check_standard, exp_uses_objfile): New declarations.
	* printcmd.c: Remove the inclusion of solib.h.
	(display_uses_solib_p): Remove the function.
	(clear_dangling_display_expressions): Call lookup_objfile_from_block
	and exp_uses_objfile instead of display_uses_solib_p.
	* solist.h (struct so_list) <objfile>: New comment.
	* symtab.c (lookup_objfile_from_block): Remove the static qualifier.
	* symtab.h (lookup_objfile_from_block): New declaration.
	(struct general_symbol_info) <obj_section>: Extend the comment.

gdb/testsuite/
	Fix crashes on dangling display expressions.
	* gdb.base/solib-display.exp: Call gdb_gnu_strip_debug if LIBSEPDEBUG
	is SEP.
	(lib_flags): Remove the "debug" keyword.
	(libsepdebug): New variable for iterating new loop.
	(save_pf_prefix): New variable wrapping the loop.
	(sep_lib_flags): New variable derived from LIB_FLAGS.  Use it.
	* lib/gdb.exp (gdb_gnu_strip_debug): Document the return code.