| /* Source locations within string literals. |
| Copyright (C) 2016-2017 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 "diagnostic.h" |
| #include "cpplib.h" |
| #include "tree.h" |
| #include "langhooks.h" |
| #include "substring-locations.h" |
| |
| /* Emit a warning governed by option OPT, using GMSGID as the format |
| string and AP as its arguments. |
| |
| Attempt to obtain precise location information within a string |
| literal from FMT_LOC. |
| |
| Case 1: if substring location is available, and is within the range of |
| the format string itself, the primary location of the |
| diagnostic is the substring range obtained from FMT_LOC, with the |
| caret at the *end* of the substring range. |
| |
| For example: |
| |
| test.c:90:10: warning: problem with '%i' here [-Wformat=] |
| printf ("hello %i", msg); |
| ~^ |
| |
| Case 2: if the substring location is available, but is not within |
| the range of the format string, the primary location is that of the |
| format string, and an note is emitted showing the substring location. |
| |
| For example: |
| test.c:90:10: warning: problem with '%i' here [-Wformat=] |
| printf("hello " INT_FMT " world", msg); |
| ^~~~~~~~~~~~~~~~~~~~~~~~~ |
| test.c:19: note: format string is defined here |
| #define INT_FMT "%i" |
| ~^ |
| |
| Case 3: if precise substring information is unavailable, the primary |
| location is that of the whole string passed to FMT_LOC's constructor. |
| For example: |
| |
| test.c:90:10: warning: problem with '%i' here [-Wformat=] |
| printf(fmt, msg); |
| ^~~ |
| |
| For each of cases 1-3, if param_range is non-NULL, then it is used |
| as a secondary range within the warning. For example, here it |
| is used with case 1: |
| |
| test.c:90:16: warning: '%s' here but arg 2 has 'long' type [-Wformat=] |
| printf ("foo %s bar", long_i + long_j); |
| ~^ ~~~~~~~~~~~~~~~ |
| |
| and here with case 2: |
| |
| test.c:90:16: warning: '%s' here but arg 2 has 'long' type [-Wformat=] |
| printf ("foo " STR_FMT " bar", long_i + long_j); |
| ^~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~ |
| test.c:89:16: note: format string is defined here |
| #define STR_FMT "%s" |
| ~^ |
| |
| and with case 3: |
| |
| test.c:90:10: warning: '%i' here, but arg 2 is "const char *' [-Wformat=] |
| printf(fmt, msg); |
| ^~~ ~~~ |
| |
| If CORRECTED_SUBSTRING is non-NULL, use it for cases 1 and 2 to provide |
| a fix-it hint, suggesting that it should replace the text within the |
| substring range. For example: |
| |
| test.c:90:10: warning: problem with '%i' here [-Wformat=] |
| printf ("hello %i", msg); |
| ~^ |
| %s |
| |
| Return true if a warning was emitted, false otherwise. */ |
| |
| ATTRIBUTE_GCC_DIAG (5,0) |
| bool |
| format_warning_va (const substring_loc &fmt_loc, |
| const source_range *param_range, |
| const char *corrected_substring, |
| int opt, const char *gmsgid, va_list *ap) |
| { |
| bool substring_within_range = false; |
| location_t primary_loc; |
| location_t fmt_substring_loc = UNKNOWN_LOCATION; |
| source_range fmt_loc_range |
| = get_range_from_loc (line_table, fmt_loc.get_fmt_string_loc ()); |
| const char *err = fmt_loc.get_location (&fmt_substring_loc); |
| source_range fmt_substring_range |
| = get_range_from_loc (line_table, fmt_substring_loc); |
| if (err) |
| /* Case 3: unable to get substring location. */ |
| primary_loc = fmt_loc.get_fmt_string_loc (); |
| else |
| { |
| if (fmt_substring_range.m_start >= fmt_loc_range.m_start |
| && fmt_substring_range.m_start <= fmt_loc_range.m_finish |
| && fmt_substring_range.m_finish >= fmt_loc_range.m_start |
| && fmt_substring_range.m_finish <= fmt_loc_range.m_finish) |
| /* Case 1. */ |
| { |
| substring_within_range = true; |
| primary_loc = fmt_substring_loc; |
| } |
| else |
| /* Case 2. */ |
| { |
| substring_within_range = false; |
| primary_loc = fmt_loc.get_fmt_string_loc (); |
| } |
| } |
| |
| rich_location richloc (line_table, primary_loc); |
| |
| if (param_range) |
| { |
| location_t param_loc = make_location (param_range->m_start, |
| param_range->m_start, |
| param_range->m_finish); |
| richloc.add_range (param_loc, false); |
| } |
| |
| if (!err && corrected_substring && substring_within_range) |
| richloc.add_fixit_replace (fmt_substring_range, corrected_substring); |
| |
| diagnostic_info diagnostic; |
| diagnostic_set_info (&diagnostic, gmsgid, ap, &richloc, DK_WARNING); |
| diagnostic.option_index = opt; |
| bool warned = report_diagnostic (&diagnostic); |
| |
| if (!err && fmt_substring_loc && !substring_within_range) |
| /* Case 2. */ |
| if (warned) |
| { |
| rich_location substring_richloc (line_table, fmt_substring_loc); |
| if (corrected_substring) |
| substring_richloc.add_fixit_replace (fmt_substring_range, |
| corrected_substring); |
| inform_at_rich_loc (&substring_richloc, |
| "format string is defined here"); |
| } |
| |
| return warned; |
| } |
| |
| /* Variadic call to format_warning_va. */ |
| |
| bool |
| format_warning_at_substring (const substring_loc &fmt_loc, |
| const source_range *param_range, |
| const char *corrected_substring, |
| int opt, const char *gmsgid, ...) |
| { |
| va_list ap; |
| va_start (ap, gmsgid); |
| bool warned = format_warning_va (fmt_loc, param_range, corrected_substring, |
| opt, gmsgid, &ap); |
| va_end (ap); |
| |
| return warned; |
| } |
| |
| /* Attempt to determine the source location of the substring. |
| If successful, return NULL and write the source location to *OUT_LOC. |
| Otherwise return an error message. Error messages are intended |
| for GCC developers (to help debugging) rather than for end-users. */ |
| |
| const char * |
| substring_loc::get_location (location_t *out_loc) const |
| { |
| gcc_assert (out_loc); |
| return lang_hooks.get_substring_location (*this, out_loc); |
| } |