1/* Support for offering suggestions for handling unrecognized names.
2 Copyright (C) 2016-2017 Free Software Foundation, Inc.
3
4This file is part of GCC.
5
6GCC is free software; you can redistribute it and/or modify it under
7the terms of the GNU General Public License as published by the Free
8Software Foundation; either version 3, or (at your option) any later
9version.
10
11GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12WARRANTY; without even the implied warranty of MERCHANTABILITY or
13FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14for more details.
15
16You should have received a copy of the GNU General Public License
17along with GCC; see the file COPYING3. If not see
18<http://www.gnu.org/licenses/>. */
19
20#ifndef GCC_NAME_HINT_H
21#define GCC_NAME_HINT_H
22
23/* This header uses gnu::unique_ptr, but unique-ptr.h can't be directly
24 included due to issues with macros. Hence it must be included from
25 system.h by defining INCLUDE_UNIQUE_PTR in any source file using it. */
26
27#ifndef GNU_UNIQUE_PTR_H
28# error "You must define INCLUDE_UNIQUE_PTR before including system.h to use name-hint.h"
29#endif
30
31enum lookup_name_fuzzy_kind {
32 /* Names of types. */
33 FUZZY_LOOKUP_TYPENAME,
34
35 /* Names of function decls. */
36 FUZZY_LOOKUP_FUNCTION_NAME,
37
38 /* Any name. */
39 FUZZY_LOOKUP_NAME
40};
41
42/* A deferred_diagnostic is a wrapper around optional extra diagnostics
43 that we may want to bundle into a name_hint.
44
45 The diagnostic is emitted by the subclass destructor, which should
46 check that is_suppressed_p () is not true. */
47
48class deferred_diagnostic
49{
50 public:
51 virtual ~deferred_diagnostic () {}
52
53 location_t get_location () const { return m_loc; }
54
55 /* Call this if the corresponding warning was not emitted,
56 in which case we should also not emit the deferred_diagnostic. */
57 void suppress ()
58 {
59 m_suppress = true;
60 }
61
62 bool is_suppressed_p () const { return m_suppress; }
63
64 protected:
65 deferred_diagnostic (location_t loc)
66 : m_loc (loc), m_suppress (false) {}
67
68 private:
69 location_t m_loc;
70 bool m_suppress;
71};
72
73/* A name_hint is an optional string suggestion, along with an
74 optional deferred_diagnostic.
75 For example:
76
77 error: unknown foo named 'bar'
78
79 if the SUGGESTION is "baz", then one might print:
80
81 error: unknown foo named 'bar'; did you mean 'baz'?
82
83 and the deferred_diagnostic allows for additional (optional)
84 diagnostics e.g.:
85
86 note: did you check behind the couch?
87
88 The deferred_diagnostic is emitted by its destructor, when the
89 name_hint goes out of scope. */
90
91class name_hint
92{
93public:
94 name_hint () : m_suggestion (NULL), m_deferred () {}
95
96 name_hint (const char *suggestion, deferred_diagnostic *deferred)
97 : m_suggestion (suggestion), m_deferred (deferred)
98 {
99 }
100
101 const char *suggestion () const { return m_suggestion; }
102 operator bool () const { return m_suggestion != NULL; }
103
104 /* Call this on a name_hint if the corresponding warning was not emitted,
105 in which case we should also not emit the deferred_diagnostic. */
106
107 void suppress ()
108 {
109 if (m_deferred)
110 m_deferred->suppress ();
111 }
112
113private:
114 const char *m_suggestion;
115 gnu::unique_ptr<deferred_diagnostic> m_deferred;
116};
117
118extern name_hint lookup_name_fuzzy (tree, enum lookup_name_fuzzy_kind,
119 location_t);
120
121#endif /* ! GCC_NAME_HINT_H */
122