Make symfile_add_flags and objfile->flags strongly typed

This makes these flag types be "enum flag" types.  The benefit is
making use of C++'s stronger typing -- mixing the flags types by
mistake errors at compile time.

This caught one old bug in symbol_file_add_main_1 already, fixed by
this patch as well:

  @@ -1318,7 +1326,7 @@ symbol_file_add_main_1 (const char *args, int from_tty, int flags)
	what is frameless.  */
     reinit_frame_cache ();

  -  if ((flags & SYMFILE_NO_READ) == 0)
  +  if ((add_flags & SYMFILE_NO_READ) == 0)
       set_initial_language ();
   }

Above, "flags" are objfile flags, not symfile_add_flags.  So that was
actually checking for "flag & OBJF_PSYMTABS_READ", which has the same
value as SYMFILE_NO_READ...

I moved the flags definitions to separate files to break circular
dependencies.

Built with --enable-targets=all and tested on x86-64 Fedora 23.

gdb/ChangeLog:
2016-10-26  Pedro Alves  <palves@redhat.com>

	* coffread.c (coff_symfile_read): Use symfile_add_flags.
	* dbxread.c (dbx_symfile_read): Ditto.
	* elfread.c (elf_symfile_read): Ditto.
	* inferior.h: Include symfile-add-flags.h.
	(struct inferior) <symfile_flags>: Now symfile_add_flags.
	* machoread.c (macho_add_oso_symfile, macho_symfile_read_all_oso)
	(macho_symfile_read, mipscoff_symfile_read): Use
	symfile_add_flags.
	* objfile-flags.h: New file.
	* objfiles.c (allocate_objfile): Use objfile_flags.
	* objfiles.h: Include objfile-flags.h.
	(struct objfile) <flags>: Now an objfile_flags.
	(OBJF_REORDERED, OBJF_SHARED, OBJF_READNOW, OBJF_USERLOADED)
	(OBJF_PSYMTABS_READ, OBJF_MAINLINE, OBJF_NOT_FILENAME): Delete.
	Converted to an enum-flags in objfile-flags.h.
	(allocate_objfile): Use objfile_flags.
	* python/py-objfile.c (objfpy_add_separate_debug_file): Remove
	unnecessary local.
	* solib.c (solib_read_symbols, solib_add)
	(reload_shared_libraries_1): Use symfile_add_flags.
	* solib.h: Include "symfile-add-flags.h".
	(solib_read_symbols): Use symfile_add_flags.
	* symfile-add-flags.h: New file.
	* symfile-debug.c (debug_sym_read): Use symfile_add_flags.
	* symfile-mem.c (symbol_file_add_from_memory): Use
	symfile_add_flags.
	* symfile.c (read_symbols, syms_from_objfile_1)
	(syms_from_objfile, finish_new_objfile): Use symfile_add_flags.
	(symbol_file_add_with_addrs): Use symfile_add_flags and
	objfile_flags.
	(symbol_file_add_separate): Use symfile_add_flags.
	(symbol_file_add_from_bfd, symbol_file_add): Use symfile_add_flags
	and objfile_flags.
	(symbol_file_add_main_1): : Use objfile_flags.  Fix add_flags vs
	flags confusion.
	(symbol_file_command): Use objfile_flags.
	(add_symbol_file_command): Use symfile_add_flags and
	objfile_flags.
	(clear_symtab_users): Use symfile_add_flags.
	* symfile.h: Include "symfile-add-flags.h" and "objfile-flags.h".
	(struct sym_fns) <sym_read>: Use symfile_add_flags.
	(clear_symtab_users): Use symfile_add_flags.
	(enum symfile_add_flags): Delete, moved to symfile-add-flags.h and
	converted to enum-flags.
	(symbol_file_add, symbol_file_add_from_bfd)
	(symbol_file_add_separate): Use symfile_add_flags.
	* xcoffread.c (xcoff_initial_scan): Use symfile_add_flags.

1 files changed, 48 insertions, 0 deletions

diff --git a/gdb/symfile-add-flags.h b/gdb/symfile-add-flags.h
new file mode 100644
index 0000000..c7f5d79
--- /dev/null
+++ b/gdb/symfile-add-flags.h
@@ -0,0 +1,48 @@
+/* Definition of symfile add flags.
+
+   Copyright (C) 1990-2016 Free Software Foundation, Inc.
+
+   This file is part of GDB.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
+
+#if !defined (SYMFILE_ADD_FLAGS_H)
+#define SYMFILE_ADD_FLAGS_H
+
+#include "common/enum-flags.h"
+
+/* This enum encodes bit-flags passed as ADD_FLAGS parameter to
+   symbol_file_add, etc.  Defined in a separate file to break circular
+   header dependencies.  */
+
+enum symfile_add_flag
+  {
+    /* Be chatty about what you are doing.  */
+    SYMFILE_VERBOSE = 1 << 1,
+
+    /* This is the main symbol file (as opposed to symbol file for
+       dynamically loaded code).  */
+    SYMFILE_MAINLINE = 1 << 2,
+
+    /* Do not call breakpoint_re_set when adding this symbol file.  */
+    SYMFILE_DEFER_BP_RESET = 1 << 3,
+
+    /* Do not immediately read symbols for this file.  By default,
+       symbols are read when the objfile is created.  */
+    SYMFILE_NO_READ = 1 << 4
+  };
+
+DEF_ENUM_FLAGS_TYPE (enum symfile_add_flag, symfile_add_flags);
+
+#endif /* !defined(SYMFILE_ADD_FLAGS_H) */