[thirdparty/gcc.git] / gcc / tree-diagnostic.c

/* Language-independent diagnostic subroutines for the GNU Compiler
   Collection that are only for use in the compilers proper and not
   the driver or other programs.
   Copyright (C) 1999-2016 Free Software Foundation, Inc.

This file is part of GCC.

GCC 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, or (at your option) any later
version.

GCC 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 GCC; see the file COPYING3.  If not see
<http://www.gnu.org/licenses/>.  */

#include "config.h"
#include "system.h"
#include "coretypes.h"
#include "tree.h"
#include "diagnostic.h"
#include "tree-pretty-print.h"
#include "tree-diagnostic.h"
#include "dumpfile.h" /* TDF_DIAGNOSTIC */
#include "langhooks.h"
#include "intl.h"

/* Prints out, if necessary, the name of the current function
   that caused an error.  Called from all error and warning functions.  */
void
diagnostic_report_current_function (diagnostic_context *context,
				    diagnostic_info *diagnostic)
{
  diagnostic_report_current_module (context, diagnostic_location (diagnostic));
  lang_hooks.print_error_function (context, LOCATION_FILE (input_location),
				   diagnostic);
}

static void
default_tree_diagnostic_starter (diagnostic_context *context,
				 diagnostic_info *diagnostic)
{
  diagnostic_report_current_function (context, diagnostic);
  pp_set_prefix (context->printer, diagnostic_build_prefix (context,
							    diagnostic));
}

/* This is a pair made of a location and the line map it originated
   from.  It's used in the maybe_unwind_expanded_macro_loc function
   below.  */
struct loc_map_pair
{
  const line_map_macro *map;
  source_location where;
};


/* Unwind the different macro expansions that lead to the token which
   location is WHERE and emit diagnostics showing the resulting
   unwound macro expansion trace.  Let's look at an example to see how
   the trace looks like.  Suppose we have this piece of code,
   artificially annotated with the line numbers to increase
   legibility:

    $ cat -n test.c
      1    #define OPERATE(OPRD1, OPRT, OPRD2) \
      2      OPRD1 OPRT OPRD2;
      3
      4    #define SHIFTL(A,B) \
      5      OPERATE (A,<<,B)
      6
      7    #define MULT(A) \
      8      SHIFTL (A,1)
      9
     10    void
     11    g ()
     12    {
     13      MULT (1.0);// 1.0 << 1; <-- so this is an error.
     14    }

   Here is the diagnostic that we want the compiler to generate:

    test.c: In function ‘g’:
    test.c:5:14: error: invalid operands to binary << (have ‘double’ and ‘int’)
    test.c:2:9: note: in definition of macro 'OPERATE'
    test.c:8:3: note: in expansion of macro 'SHIFTL'
    test.c:13:3: note: in expansion of macro 'MULT'

   The part that goes from the third to the fifth line of this
   diagnostic (the lines containing the 'note:' string) is called the
   unwound macro expansion trace.  That's the part generated by this
   function.  */

static void
maybe_unwind_expanded_macro_loc (diagnostic_context *context,
                                 const diagnostic_info *diagnostic,
                                 source_location where)
{
  const struct line_map *map;
  auto_vec<loc_map_pair> loc_vec;
  unsigned ix;
  loc_map_pair loc, *iter;

  map = linemap_lookup (line_table, where);
  if (!linemap_macro_expansion_map_p (map))
    return;

  /* Let's unwind the macros that got expanded and led to the token
     which location is WHERE.  We are going to store these macros into
     LOC_VEC, so that we can later walk it at our convenience to
     display a somewhat meaningful trace of the macro expansion
     history to the user.  Note that the first macro of the trace
     (which is OPERATE in the example above) is going to be stored at
     the beginning of LOC_VEC.  */

  do
    {
      loc.where = where;
      loc.map = linemap_check_macro (map);

      loc_vec.safe_push (loc);

      /* WHERE is the location of a token inside the expansion of a
         macro.  MAP is the map holding the locations of that macro
         expansion.  Let's get the location of the token inside the
         context that triggered the expansion of this macro.
         This is basically how we go "down" in the trace of macro
         expansions that led to WHERE.  */
      where = linemap_unwind_toward_expansion (line_table, where, &map);
    } while (linemap_macro_expansion_map_p (map));

  /* Now map is set to the map of the location in the source that
     first triggered the macro expansion.  This must be an ordinary map.  */
  const line_map_ordinary *ord_map = linemap_check_ordinary (map);

  /* Walk LOC_VEC and print the macro expansion trace, unless the
     first macro which expansion triggered this trace was expanded
     inside a system header.  */
  int saved_location_line =
    expand_location_to_spelling_point (diagnostic_location (diagnostic)).line;

  if (!LINEMAP_SYSP (ord_map))
    FOR_EACH_VEC_ELT (loc_vec, ix, iter)
      {
	/* Sometimes, in the unwound macro expansion trace, we want to
	   print a part of the context that shows where, in the
	   definition of the relevant macro, is the token (we are
	   looking at) used.  That is the case in the introductory
	   comment of this function, where we print:

	       test.c:2:9: note: in definition of macro 'OPERATE'.

	   We print that "macro definition context" because the
	   diagnostic line (emitted by the call to
	   pp_ouput_formatted_text in diagnostic_report_diagnostic):

	       test.c:5:14: error: invalid operands to binary << (have ‘double’ and ‘int’)

	   does not point into the definition of the macro where the
	   token '<<' (that is an argument to the function-like macro
	   OPERATE) is used.  So we must "display" the line of that
	   macro definition context to the user somehow.

	   A contrario, when the first interesting diagnostic line
	   points into the definition of the macro, we don't need to
	   display any line for that macro definition in the trace
	   anymore, otherwise it'd be redundant.  */

        /* Okay, now here is what we want.  For each token resulting
           from macro expansion we want to show: 1/ where in the
           definition of the macro the token comes from; 2/ where the
           macro got expanded.  */

        /* Resolve the location iter->where into the locus 1/ of the
           comment above.  */
        source_location resolved_def_loc =
          linemap_resolve_location (line_table, iter->where,
                                    LRK_MACRO_DEFINITION_LOCATION, NULL);

	/* Don't print trace for locations that are reserved or from
	   within a system header.  */
        const line_map_ordinary *m = NULL;
        source_location l = 
          linemap_resolve_location (line_table, resolved_def_loc,
                                    LRK_SPELLING_LOCATION,  &m);
        if (l < RESERVED_LOCATION_COUNT || LINEMAP_SYSP (m))
          continue;
        
	/* We need to print the context of the macro definition only
	   when the locus of the first displayed diagnostic (displayed
	   before this trace) was inside the definition of the
	   macro.  */
        int resolved_def_loc_line = SOURCE_LINE (m, l);
        if (ix == 0 && saved_location_line != resolved_def_loc_line)
          {
            diagnostic_append_note (context, resolved_def_loc, 
                                    "in definition of macro %qs",
                                    linemap_map_get_macro_name (iter->map));
            /* At this step, as we've printed the context of the macro
               definition, we don't want to print the context of its
               expansion, otherwise, it'd be redundant.  */
            continue;
          }

        /* Resolve the location of the expansion point of the macro
           which expansion gave the token represented by def_loc.
           This is the locus 2/ of the earlier comment.  */
        source_location resolved_exp_loc =
          linemap_resolve_location (line_table,
                                    MACRO_MAP_EXPANSION_POINT_LOCATION (iter->map),
                                    LRK_MACRO_DEFINITION_LOCATION, NULL);

        diagnostic_append_note (context, resolved_exp_loc, 
                                "in expansion of macro %qs",
                                linemap_map_get_macro_name (iter->map));
      }
}

/*  This is a diagnostic finalizer implementation that is aware of
    virtual locations produced by libcpp.

    It has to be called by the diagnostic finalizer of front ends that
    uses libcpp and wish to get diagnostics involving tokens resulting
    from macro expansion.

    For a given location, if said location belongs to a token
    resulting from a macro expansion, this starter prints the context
    of the token.  E.g, for multiply nested macro expansion, it
    unwinds the nested macro expansions and prints them in a manner
    that is similar to what is done for function call stacks, or
    template instantiation contexts.  */
void
virt_loc_aware_diagnostic_finalizer (diagnostic_context *context,
				     diagnostic_info *diagnostic)
{
  maybe_unwind_expanded_macro_loc (context, diagnostic,
				   diagnostic_location (diagnostic));
}

/* Default tree printer.   Handles declarations only.  */
static bool
default_tree_printer (pretty_printer *pp, text_info *text, const char *spec,
		      int precision, bool wide, bool set_locus, bool hash)
{
  tree t;

  /* FUTURE: %+x should set the locus.  */
  if (precision != 0 || wide || hash)
    return false;

  switch (*spec)
    {
    case 'E':
      t = va_arg (*text->args_ptr, tree);
      if (TREE_CODE (t) == IDENTIFIER_NODE)
	{
	  pp_identifier (pp, IDENTIFIER_POINTER (t));
	  return true;
	}
      break;

    case 'D':
      t = va_arg (*text->args_ptr, tree);
      if (VAR_P (t) && DECL_HAS_DEBUG_EXPR_P (t))
	t = DECL_DEBUG_EXPR (t);
      break;

    case 'F':
    case 'T':
      t = va_arg (*text->args_ptr, tree);
      break;

    case 'K':
      percent_K_format (text);
      return true;

    default:
      return false;
    }

  if (set_locus)
    text->set_location (0, DECL_SOURCE_LOCATION (t), true);

  if (DECL_P (t))
    {
      const char *n = DECL_NAME (t)
        ? identifier_to_locale (lang_hooks.decl_printable_name (t, 2))
        : _("<anonymous>");
      pp_string (pp, n);
    }
  else
    dump_generic_node (pp, t, 0, TDF_DIAGNOSTIC, 0);

  return true;
}

/* Sets CONTEXT to use language independent diagnostics.  */
void
tree_diagnostics_defaults (diagnostic_context *context)
{
  diagnostic_starter (context) = default_tree_diagnostic_starter;
  diagnostic_finalizer (context) = default_diagnostic_finalizer;
  diagnostic_format_decoder (context) = default_tree_printer;
}
Commit	Line	Data
cf835838 JM	1	/* Language-independent diagnostic subroutines for the GNU Compiler
	2	Collection that are only for use in the compilers proper and not
	3	the driver or other programs.
818ab71a	4	Copyright (C) 1999-2016 Free Software Foundation, Inc.
cf835838 JM	5
	6	This file is part of GCC.
	7
	8	GCC is free software; you can redistribute it and/or modify it under
	9	the terms of the GNU General Public License as published by the Free
	10	Software Foundation; either version 3, or (at your option) any later
	11	version.
	12
	13	GCC is distributed in the hope that it will be useful, but WITHOUT ANY
	14	WARRANTY; without even the implied warranty of MERCHANTABILITY or
	15	FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
	16	for more details.
	17
	18	You should have received a copy of the GNU General Public License
	19	along with GCC; see the file COPYING3. If not see
	20	<http://www.gnu.org/licenses/>. */
	21
	22	#include "config.h"
	23	#include "system.h"
	24	#include "coretypes.h"
957060b5	25	#include "tree.h"
cf835838	26	#include "diagnostic.h"
21e41715	27	#include "tree-pretty-print.h"
cf835838	28	#include "tree-diagnostic.h"
7ee2468b	29	#include "dumpfile.h" /* TDF_DIAGNOSTIC */
cf835838	30	#include "langhooks.h"
21e41715	31	#include "intl.h"
cf835838 JM	32
	33	/* Prints out, if necessary, the name of the current function
	34	that caused an error. Called from all error and warning functions. */
	35	void
	36	diagnostic_report_current_function (diagnostic_context *context,
	37	diagnostic_info *diagnostic)
	38	{
2a2703a2	39	diagnostic_report_current_module (context, diagnostic_location (diagnostic));
8400e75e DM	40	lang_hooks.print_error_function (context, LOCATION_FILE (input_location),
8400e75e DM	41	diagnostic);
cf835838 JM	42	}
cf835838 JM	43
21e41715	44	static void
cf835838 JM	45	default_tree_diagnostic_starter (diagnostic_context *context,
	46	diagnostic_info *diagnostic)
	47	{
	48	diagnostic_report_current_function (context, diagnostic);
243fbddd JM	49	pp_set_prefix (context->printer, diagnostic_build_prefix (context,
243fbddd JM	50	diagnostic));
cf835838	51	}
07a0b324 TT	52
	53	/* This is a pair made of a location and the line map it originated
	54	from. It's used in the maybe_unwind_expanded_macro_loc function
	55	below. */
a79683d5	56	struct loc_map_pair
07a0b324	57	{
0e50b624	58	const line_map_macro *map;
07a0b324	59	source_location where;
a79683d5	60	};
07a0b324	61
07a0b324 TT	62
	63	/* Unwind the different macro expansions that lead to the token which
	64	location is WHERE and emit diagnostics showing the resulting
	65	unwound macro expansion trace. Let's look at an example to see how
	66	the trace looks like. Suppose we have this piece of code,
	67	artificially annotated with the line numbers to increase
	68	legibility:
	69
	70	$ cat -n test.c
	71	1 #define OPERATE(OPRD1, OPRT, OPRD2) \
	72	2 OPRD1 OPRT OPRD2;
	73	3
	74	4 #define SHIFTL(A,B) \
	75	5 OPERATE (A,<<,B)
	76	6
	77	7 #define MULT(A) \
	78	8 SHIFTL (A,1)
	79	9
	80	10 void
	81	11 g ()
	82	12 {
	83	13 MULT (1.0);// 1.0 << 1; <-- so this is an error.
	84	14 }
	85
	86	Here is the diagnostic that we want the compiler to generate:
	87
165ca58d DS	88	test.c: In function ‘g’:
	89	test.c:5:14: error: invalid operands to binary << (have ‘double’ and ‘int’)
	90	test.c:2:9: note: in definition of macro 'OPERATE'
	91	test.c:8:3: note: in expansion of macro 'SHIFTL'
	92	test.c:13:3: note: in expansion of macro 'MULT'
	93
	94	The part that goes from the third to the fifth line of this
07a0b324 TT	95	diagnostic (the lines containing the 'note:' string) is called the
07a0b324 TT	96	unwound macro expansion trace. That's the part generated by this
1d72e96f	97	function. */
07a0b324 TT	98
	99	static void
	100	maybe_unwind_expanded_macro_loc (diagnostic_context *context,
dfa32261	101	const diagnostic_info *diagnostic,
1d72e96f	102	source_location where)
07a0b324 TT	103	{
07a0b324 TT	104	const struct line_map *map;
8c681247	105	auto_vec<loc_map_pair> loc_vec;
07a0b324	106	unsigned ix;
8f5c9d66	107	loc_map_pair loc, *iter;
07a0b324 TT	108
	109	map = linemap_lookup (line_table, where);
	110	if (!linemap_macro_expansion_map_p (map))
	111	return;
	112
	113	/* Let's unwind the macros that got expanded and led to the token
	114	which location is WHERE. We are going to store these macros into
	115	LOC_VEC, so that we can later walk it at our convenience to
	116	display a somewhat meaningful trace of the macro expansion
	117	history to the user. Note that the first macro of the trace
	118	(which is OPERATE in the example above) is going to be stored at
	119	the beginning of LOC_VEC. */
	120
	121	do
	122	{
	123	loc.where = where;
0e50b624	124	loc.map = linemap_check_macro (map);
07a0b324	125
9771b263	126	loc_vec.safe_push (loc);
07a0b324 TT	127
	128	/* WHERE is the location of a token inside the expansion of a
	129	macro. MAP is the map holding the locations of that macro
	130	expansion. Let's get the location of the token inside the
	131	context that triggered the expansion of this macro.
	132	This is basically how we go "down" in the trace of macro
	133	expansions that led to WHERE. */
	134	where = linemap_unwind_toward_expansion (line_table, where, &map);
	135	} while (linemap_macro_expansion_map_p (map));
	136
1d72e96f MLI	137	/* Now map is set to the map of the location in the source that
1d72e96f MLI	138	first triggered the macro expansion. This must be an ordinary map. */
0e50b624	139	const line_map_ordinary *ord_map = linemap_check_ordinary (map);
07a0b324 TT	140
	141	/* Walk LOC_VEC and print the macro expansion trace, unless the
	142	first macro which expansion triggered this trace was expanded
	143	inside a system header. */
dfa32261	144	int saved_location_line =
2a2703a2	145	expand_location_to_spelling_point (diagnostic_location (diagnostic)).line;
dfa32261	146
0e50b624	147	if (!LINEMAP_SYSP (ord_map))
9771b263	148	FOR_EACH_VEC_ELT (loc_vec, ix, iter)
07a0b324	149	{
165ca58d DS	150	/* Sometimes, in the unwound macro expansion trace, we want to
	151	print a part of the context that shows where, in the
	152	definition of the relevant macro, is the token (we are
	153	looking at) used. That is the case in the introductory
	154	comment of this function, where we print:
	155
	156	test.c:2:9: note: in definition of macro 'OPERATE'.
	157
	158	We print that "macro definition context" because the
	159	diagnostic line (emitted by the call to
	160	pp_ouput_formatted_text in diagnostic_report_diagnostic):
	161
	162	test.c:5:14: error: invalid operands to binary << (have ‘double’ and ‘int’)
	163
	164	does not point into the definition of the macro where the
	165	token '<<' (that is an argument to the function-like macro
	166	OPERATE) is used. So we must "display" the line of that
	167	macro definition context to the user somehow.
	168
	169	A contrario, when the first interesting diagnostic line
	170	points into the definition of the macro, we don't need to
	171	display any line for that macro definition in the trace
dfa32261	172	anymore, otherwise it'd be redundant. */
07a0b324 TT	173
	174	/* Okay, now here is what we want. For each token resulting
	175	from macro expansion we want to show: 1/ where in the
	176	definition of the macro the token comes from; 2/ where the
	177	macro got expanded. */
	178
	179	/* Resolve the location iter->where into the locus 1/ of the
	180	comment above. */
dfa32261	181	source_location resolved_def_loc =
07a0b324 TT	182	linemap_resolve_location (line_table, iter->where,
	183	LRK_MACRO_DEFINITION_LOCATION, NULL);
	184
c4ca1a09 DS	185	/* Don't print trace for locations that are reserved or from
c4ca1a09 DS	186	within a system header. */
0e50b624	187	const line_map_ordinary *m = NULL;
dfa32261 MLI	188	source_location l =
	189	linemap_resolve_location (line_table, resolved_def_loc,
	190	LRK_SPELLING_LOCATION, &m);
	191	if (l < RESERVED_LOCATION_COUNT \|\| LINEMAP_SYSP (m))
	192	continue;
	193
	194	/* We need to print the context of the macro definition only
	195	when the locus of the first displayed diagnostic (displayed
	196	before this trace) was inside the definition of the
	197	macro. */
	198	int resolved_def_loc_line = SOURCE_LINE (m, l);
	199	if (ix == 0 && saved_location_line != resolved_def_loc_line)
	200	{
	201	diagnostic_append_note (context, resolved_def_loc,
	202	"in definition of macro %qs",
	203	linemap_map_get_macro_name (iter->map));
	204	/* At this step, as we've printed the context of the macro
	205	definition, we don't want to print the context of its
	206	expansion, otherwise, it'd be redundant. */
	207	continue;
	208	}
c4ca1a09	209
07a0b324 TT	210	/* Resolve the location of the expansion point of the macro
	211	which expansion gave the token represented by def_loc.
	212	This is the locus 2/ of the earlier comment. */
dfa32261	213	source_location resolved_exp_loc =
07a0b324 TT	214	linemap_resolve_location (line_table,
	215	MACRO_MAP_EXPANSION_POINT_LOCATION (iter->map),
	216	LRK_MACRO_DEFINITION_LOCATION, NULL);
	217
dfa32261 MLI	218	diagnostic_append_note (context, resolved_exp_loc,
	219	"in expansion of macro %qs",
	220	linemap_map_get_macro_name (iter->map));
07a0b324	221	}
07a0b324 TT	222	}
	223
	224	/* This is a diagnostic finalizer implementation that is aware of
	225	virtual locations produced by libcpp.
	226
	227	It has to be called by the diagnostic finalizer of front ends that
	228	uses libcpp and wish to get diagnostics involving tokens resulting
	229	from macro expansion.
	230
	231	For a given location, if said location belongs to a token
	232	resulting from a macro expansion, this starter prints the context
	233	of the token. E.g, for multiply nested macro expansion, it
	234	unwinds the nested macro expansions and prints them in a manner
	235	that is similar to what is done for function call stacks, or
	236	template instantiation contexts. */
	237	void
	238	virt_loc_aware_diagnostic_finalizer (diagnostic_context *context,
	239	diagnostic_info *diagnostic)
	240	{
	241	maybe_unwind_expanded_macro_loc (context, diagnostic,
2a2703a2	242	diagnostic_location (diagnostic));
07a0b324	243	}
21e41715 MLI	244
	245	/* Default tree printer. Handles declarations only. */
	246	static bool
	247	default_tree_printer (pretty_printer pp, text_info text, const char *spec,
	248	int precision, bool wide, bool set_locus, bool hash)
	249	{
	250	tree t;
	251
	252	/* FUTURE: %+x should set the locus. */
	253	if (precision != 0 \|\| wide \|\| hash)
	254	return false;
	255
	256	switch (*spec)
	257	{
	258	case 'E':
	259	t = va_arg (*text->args_ptr, tree);
	260	if (TREE_CODE (t) == IDENTIFIER_NODE)
	261	{
	262	pp_identifier (pp, IDENTIFIER_POINTER (t));
	263	return true;
	264	}
	265	break;
	266
	267	case 'D':
	268	t = va_arg (*text->args_ptr, tree);
8813a647	269	if (VAR_P (t) && DECL_HAS_DEBUG_EXPR_P (t))
21e41715 MLI	270	t = DECL_DEBUG_EXPR (t);
	271	break;
	272
	273	case 'F':
	274	case 'T':
	275	t = va_arg (*text->args_ptr, tree);
	276	break;
	277
	278	case 'K':
	279	percent_K_format (text);
	280	return true;
	281
	282	default:
	283	return false;
	284	}
	285
2a2703a2	286	if (set_locus)
8a645150	287	text->set_location (0, DECL_SOURCE_LOCATION (t), true);
21e41715 MLI	288
	289	if (DECL_P (t))
	290	{
	291	const char *n = DECL_NAME (t)
	292	? identifier_to_locale (lang_hooks.decl_printable_name (t, 2))
	293	: _("<anonymous>");
	294	pp_string (pp, n);
	295	}
	296	else
	297	dump_generic_node (pp, t, 0, TDF_DIAGNOSTIC, 0);
	298
	299	return true;
	300	}
	301
	302	/* Sets CONTEXT to use language independent diagnostics. */
	303	void
	304	tree_diagnostics_defaults (diagnostic_context *context)
	305	{
	306	diagnostic_starter (context) = default_tree_diagnostic_starter;
	307	diagnostic_finalizer (context) = default_diagnostic_finalizer;
	308	diagnostic_format_decoder (context) = default_tree_printer;
	309	}