1 /* Functions for deciding which macros are currently in scope.
2 Copyright (C) 2002-2013 Free Software Foundation, Inc.
3 Contributed by Red Hat, Inc.
5 This file is part of GDB.
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 3 of the License, or
10 (at your option) any later version.
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with this program. If not, see <http://www.gnu.org/licenses/>. */
22 #include "macroscope.h"
28 #include "complaints.h"
30 /* A table of user-defined macros. Unlike the macro tables used for
31 symtabs, this one uses xmalloc for all its allocation, not an
32 obstack, and it doesn't bcache anything; it just xmallocs things. So
33 it's perfectly possible to remove things from this, or redefine
35 struct macro_table *macro_user_macros;
39 sal_macro_scope (struct symtab_and_line sal)
41 struct macro_source_file *main_file, *inclusion;
42 struct macro_scope *ms;
45 || ! sal.symtab->macro_table)
48 ms = (struct macro_scope *) xmalloc (sizeof (*ms));
50 main_file = macro_main (sal.symtab->macro_table);
51 inclusion = macro_lookup_inclusion (main_file, sal.symtab->filename);
60 /* There are, unfortunately, cases where a compilation unit can
61 have a symtab for a source file that doesn't appear in the
62 macro table. For example, at the moment, Dwarf doesn't have
63 any way in the .debug_macinfo section to describe the effect
64 of #line directives, so if you debug a YACC parser you'll get
65 a macro table which only mentions the .c files generated by
66 YACC, but symtabs that mention the .y files consumed by YACC.
68 In the long run, we should extend the Dwarf macro info
69 representation to handle #line directives, and get GCC to
72 For the time being, though, we'll just treat these as
73 occurring at the end of the main source file. */
77 complaint (&symfile_complaints,
78 _("symtab found for `%s', but that file\n"
79 "is not covered in the compilation unit's macro information"),
80 symtab_to_filename_for_display (sal.symtab));
88 user_macro_scope (void)
90 struct macro_scope *ms;
92 ms = XNEW (struct macro_scope);
93 ms->file = macro_main (macro_user_macros);
99 default_macro_scope (void)
101 struct symtab_and_line sal;
102 struct macro_scope *ms;
103 struct frame_info *frame;
106 /* If there's a selected frame, use its PC. */
107 frame = deprecated_safe_get_selected_frame ();
108 if (frame && get_frame_pc_if_available (frame, &pc))
109 sal = find_pc_line (pc, 0);
111 /* Fall back to the current listing position. */
114 /* Don't call select_source_symtab here. That can raise an
115 error if symbols aren't loaded, but GDB calls the expression
116 evaluator in all sorts of contexts.
118 For example, commands like `set width' call the expression
119 evaluator to evaluate their numeric arguments. If the
120 current language is C, then that may call this function to
121 choose a scope for macro expansion. If you don't have any
122 symbol files loaded, then get_current_or_default would raise an
123 error. But `set width' shouldn't raise an error just because
124 it can't decide which scope to macro-expand its argument in. */
125 struct symtab_and_line cursal =
126 get_current_source_symtab_and_line ();
128 sal.symtab = cursal.symtab;
129 sal.line = cursal.line;
132 ms = sal_macro_scope (sal);
134 ms = user_macro_scope ();
140 /* Look up the definition of the macro named NAME in scope at the source
141 location given by BATON, which must be a pointer to a `struct
142 macro_scope' structure. */
143 struct macro_definition *
144 standard_macro_lookup (const char *name, void *baton)
146 struct macro_scope *ms = (struct macro_scope *) baton;
147 struct macro_definition *result;
149 /* Give user-defined macros priority over all others. */
150 result = macro_lookup_definition (macro_main (macro_user_macros), -1, name);
152 result = macro_lookup_definition (ms->file, ms->line, name);
156 /* Provide a prototype to silence -Wmissing-prototypes. */
157 extern initialize_file_ftype _initialize_macroscope;
160 _initialize_macroscope (void)
162 macro_user_macros = new_macro_table (0, 0);
163 macro_set_main (macro_user_macros, "<user-defined>");
164 macro_allow_redefinitions (macro_user_macros);