diff options
Diffstat (limited to 'gcc/substring-locations.c')
| -rw-r--r-- | gcc/substring-locations.c | 195 |
1 files changed, 195 insertions, 0 deletions
diff --git a/gcc/substring-locations.c b/gcc/substring-locations.c new file mode 100644 index 0000000..60bf1b0 --- /dev/null +++ b/gcc/substring-locations.c @@ -0,0 +1,195 @@ +/* Source locations within string literals. + Copyright (C) 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 "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_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); +} |