1 /* Check calls to formatted I/O functions (-Wformat).
2 Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
3 2001, 2002, 2003, 2004 Free Software Foundation, Inc.
5 This file is part of GCC.
7 GCC is free software; you can redistribute it and/or modify it under
8 the terms of the GNU General Public License as published by the Free
9 Software Foundation; either version 2, or (at your option) any later
12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING. If not, write to the Free
19 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
24 #include "coretypes.h"
31 #include "diagnostic.h"
32 #include "langhooks.h"
35 /* Set format warning options according to a -Wformat=n option. */
38 set_Wformat (int setting)
40 warn_format = setting;
41 warn_format_extra_args = setting;
42 warn_format_zero_length = setting;
45 warn_format_nonliteral = setting;
46 warn_format_security = setting;
47 warn_format_y2k = setting;
49 /* Make sure not to disable -Wnonnull if -Wformat=0 is specified. */
51 warn_nonnull = setting;
55 /* Handle attributes associated with format checking. */
57 /* This must be in the same order as format_types, except for
58 format_type_error. Target-specific format types do not have
59 matching enum values. */
60 enum format_type { printf_format_type, asm_fprintf_format_type,
61 gcc_diag_format_type, gcc_cdiag_format_type,
62 gcc_cxxdiag_format_type,
63 scanf_format_type, strftime_format_type,
64 strfmon_format_type, format_type_error = -1};
66 typedef struct function_format_info
68 int format_type; /* type of format (printf, scanf, etc.) */
69 unsigned HOST_WIDE_INT format_num; /* number of format argument */
70 unsigned HOST_WIDE_INT first_arg_num; /* number of first arg (zero for varargs) */
71 } function_format_info;
73 static bool decode_format_attr (tree, function_format_info *, int);
74 static int decode_format_type (const char *);
76 static bool check_format_string (tree argument,
77 unsigned HOST_WIDE_INT format_num,
78 int flags, bool *no_add_attrs);
79 static bool get_constant (tree expr, unsigned HOST_WIDE_INT *value,
83 /* Handle a "format_arg" attribute; arguments as in
84 struct attribute_spec.handler. */
86 handle_format_arg_attribute (tree *node, tree ARG_UNUSED (name),
87 tree args, int flags, bool *no_add_attrs)
90 tree format_num_expr = TREE_VALUE (args);
91 unsigned HOST_WIDE_INT format_num = 0;
94 if (!get_constant (format_num_expr, &format_num, 0))
96 error ("format string has invalid operand number");
101 argument = TYPE_ARG_TYPES (type);
104 if (!check_format_string (argument, format_num, flags, no_add_attrs))
108 if (TREE_CODE (TREE_TYPE (type)) != POINTER_TYPE
109 || (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (type)))
112 if (!(flags & (int) ATTR_FLAG_BUILT_IN))
113 error ("function does not return string type");
114 *no_add_attrs = true;
121 /* Verify that the format_num argument is actually a string, in case
122 the format attribute is in error. */
124 check_format_string (tree argument, unsigned HOST_WIDE_INT format_num,
125 int flags, bool *no_add_attrs)
127 unsigned HOST_WIDE_INT i;
129 for (i = 1; i != format_num; i++)
133 argument = TREE_CHAIN (argument);
137 || TREE_CODE (TREE_VALUE (argument)) != POINTER_TYPE
138 || (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_VALUE (argument)))
141 if (!(flags & (int) ATTR_FLAG_BUILT_IN))
142 error ("format string argument not a string type");
143 *no_add_attrs = true;
150 /* Strip any conversions from the expression, verify it is a constant,
151 and store its value. If validated_p is true, abort on errors.
152 Returns true on success, false otherwise. */
154 get_constant (tree expr, unsigned HOST_WIDE_INT *value, int validated_p)
156 while (TREE_CODE (expr) == NOP_EXPR
157 || TREE_CODE (expr) == CONVERT_EXPR
158 || TREE_CODE (expr) == NON_LVALUE_EXPR)
159 expr = TREE_OPERAND (expr, 0);
161 if (TREE_CODE (expr) != INTEGER_CST || TREE_INT_CST_HIGH (expr) != 0)
163 gcc_assert (!validated_p);
167 *value = TREE_INT_CST_LOW (expr);
172 /* Decode the arguments to a "format" attribute into a function_format_info
173 structure. It is already known that the list is of the right length.
174 If VALIDATED_P is true, then these attributes have already been validated
175 and this function will abort if they are erroneous; if false, it
176 will give an error message. Returns true if the attributes are
177 successfully decoded, false otherwise. */
180 decode_format_attr (tree args, function_format_info *info, int validated_p)
182 tree format_type_id = TREE_VALUE (args);
183 tree format_num_expr = TREE_VALUE (TREE_CHAIN (args));
184 tree first_arg_num_expr
185 = TREE_VALUE (TREE_CHAIN (TREE_CHAIN (args)));
187 if (TREE_CODE (format_type_id) != IDENTIFIER_NODE)
189 gcc_assert (!validated_p);
190 error ("unrecognized format specifier");
195 const char *p = IDENTIFIER_POINTER (format_type_id);
197 info->format_type = decode_format_type (p);
199 if (info->format_type == format_type_error)
201 gcc_assert (!validated_p);
202 warning ("%qE is an unrecognized format function type",
208 if (!get_constant (format_num_expr, &info->format_num, validated_p))
210 error ("format string has invalid operand number");
214 if (!get_constant (first_arg_num_expr, &info->first_arg_num, validated_p))
216 error ("%<...%> has invalid operand number");
220 if (info->first_arg_num != 0 && info->first_arg_num <= info->format_num)
222 gcc_assert (!validated_p);
223 error ("format string argument follows the args to be formatted");
230 /* Check a call to a format function against a parameter list. */
232 /* The C standard version C++ is treated as equivalent to
233 or inheriting from, for the purpose of format features supported. */
234 #define CPLUSPLUS_STD_VER STD_C94
235 /* The C standard version we are checking formats against when pedantic. */
236 #define C_STD_VER ((int) (c_dialect_cxx () \
237 ? CPLUSPLUS_STD_VER \
240 : (flag_isoc94 ? STD_C94 : STD_C89))))
241 /* The name to give to the standard version we are warning about when
242 pedantic. FEATURE_VER is the version in which the feature warned out
243 appeared, which is higher than C_STD_VER. */
244 #define C_STD_NAME(FEATURE_VER) (c_dialect_cxx () \
246 : ((FEATURE_VER) == STD_EXT \
249 /* Adjust a C standard version, which may be STD_C9L, to account for
250 -Wno-long-long. Returns other standard versions unchanged. */
251 #define ADJ_STD(VER) ((int) ((VER) == STD_C9L \
252 ? (warn_long_long ? STD_C99 : STD_C89) \
255 /* Structure describing details of a type expected in format checking,
256 and the type to check against it. */
257 typedef struct format_wanted_type
259 /* The type wanted. */
261 /* The name of this type to use in diagnostics. */
262 const char *wanted_type_name;
263 /* The level of indirection through pointers at which this type occurs. */
265 /* Whether, when pointer_count is 1, to allow any character type when
266 pedantic, rather than just the character or void type specified. */
267 int char_lenient_flag;
268 /* Whether the argument, dereferenced once, is written into and so the
269 argument must not be a pointer to a const-qualified type. */
271 /* Whether the argument, dereferenced once, is read from and so
272 must not be a NULL pointer. */
273 int reading_from_flag;
274 /* If warnings should be of the form "field precision should have
275 type 'int'", the name to use (in this case "field precision"),
276 otherwise NULL, for "format expects type 'long'" type
279 /* The actual parameter to check against the wanted type. */
281 /* The argument number of that parameter. */
283 /* The next type to check for this format conversion, or NULL if none. */
284 struct format_wanted_type *next;
285 } format_wanted_type;
288 static const format_length_info printf_length_specs[] =
290 { "h", FMT_LEN_h, STD_C89, "hh", FMT_LEN_hh, STD_C99 },
291 { "l", FMT_LEN_l, STD_C89, "ll", FMT_LEN_ll, STD_C9L },
292 { "q", FMT_LEN_ll, STD_EXT, NULL, 0, 0 },
293 { "L", FMT_LEN_L, STD_C89, NULL, 0, 0 },
294 { "z", FMT_LEN_z, STD_C99, NULL, 0, 0 },
295 { "Z", FMT_LEN_z, STD_EXT, NULL, 0, 0 },
296 { "t", FMT_LEN_t, STD_C99, NULL, 0, 0 },
297 { "j", FMT_LEN_j, STD_C99, NULL, 0, 0 },
298 { NULL, 0, 0, NULL, 0, 0 }
301 /* Length specifiers valid for asm_fprintf. */
302 static const format_length_info asm_fprintf_length_specs[] =
304 { "l", FMT_LEN_l, STD_C89, "ll", FMT_LEN_ll, STD_C89 },
305 { "w", FMT_LEN_none, STD_C89, NULL, 0, 0 },
306 { NULL, 0, 0, NULL, 0, 0 }
309 /* Length specifiers valid for GCC diagnostics. */
310 static const format_length_info gcc_diag_length_specs[] =
312 { "l", FMT_LEN_l, STD_C89, "ll", FMT_LEN_ll, STD_C89 },
313 { "w", FMT_LEN_none, STD_C89, NULL, 0, 0 },
314 { NULL, 0, 0, NULL, 0, 0 }
317 /* The custom diagnostics all accept the same length specifiers. */
318 #define gcc_cdiag_length_specs gcc_diag_length_specs
319 #define gcc_cxxdiag_length_specs gcc_diag_length_specs
321 /* This differs from printf_length_specs only in that "Z" is not accepted. */
322 static const format_length_info scanf_length_specs[] =
324 { "h", FMT_LEN_h, STD_C89, "hh", FMT_LEN_hh, STD_C99 },
325 { "l", FMT_LEN_l, STD_C89, "ll", FMT_LEN_ll, STD_C9L },
326 { "q", FMT_LEN_ll, STD_EXT, NULL, 0, 0 },
327 { "L", FMT_LEN_L, STD_C89, NULL, 0, 0 },
328 { "z", FMT_LEN_z, STD_C99, NULL, 0, 0 },
329 { "t", FMT_LEN_t, STD_C99, NULL, 0, 0 },
330 { "j", FMT_LEN_j, STD_C99, NULL, 0, 0 },
331 { NULL, 0, 0, NULL, 0, 0 }
335 /* All tables for strfmon use STD_C89 everywhere, since -pedantic warnings
336 make no sense for a format type not part of any C standard version. */
337 static const format_length_info strfmon_length_specs[] =
339 /* A GNU extension. */
340 { "L", FMT_LEN_L, STD_C89, NULL, 0, 0 },
341 { NULL, 0, 0, NULL, 0, 0 }
344 static const format_flag_spec printf_flag_specs[] =
346 { ' ', 0, 0, N_("' ' flag"), N_("the ' ' printf flag"), STD_C89 },
347 { '+', 0, 0, N_("'+' flag"), N_("the '+' printf flag"), STD_C89 },
348 { '#', 0, 0, N_("'#' flag"), N_("the '#' printf flag"), STD_C89 },
349 { '0', 0, 0, N_("'0' flag"), N_("the '0' printf flag"), STD_C89 },
350 { '-', 0, 0, N_("'-' flag"), N_("the '-' printf flag"), STD_C89 },
351 { '\'', 0, 0, N_("''' flag"), N_("the ''' printf flag"), STD_EXT },
352 { 'I', 0, 0, N_("'I' flag"), N_("the 'I' printf flag"), STD_EXT },
353 { 'w', 0, 0, N_("field width"), N_("field width in printf format"), STD_C89 },
354 { 'p', 0, 0, N_("precision"), N_("precision in printf format"), STD_C89 },
355 { 'L', 0, 0, N_("length modifier"), N_("length modifier in printf format"), STD_C89 },
356 { 0, 0, 0, NULL, NULL, 0 }
360 static const format_flag_pair printf_flag_pairs[] =
364 { '0', 'p', 1, 'i' },
368 static const format_flag_spec asm_fprintf_flag_specs[] =
370 { ' ', 0, 0, N_("' ' flag"), N_("the ' ' printf flag"), STD_C89 },
371 { '+', 0, 0, N_("'+' flag"), N_("the '+' printf flag"), STD_C89 },
372 { '#', 0, 0, N_("'#' flag"), N_("the '#' printf flag"), STD_C89 },
373 { '0', 0, 0, N_("'0' flag"), N_("the '0' printf flag"), STD_C89 },
374 { '-', 0, 0, N_("'-' flag"), N_("the '-' printf flag"), STD_C89 },
375 { 'w', 0, 0, N_("field width"), N_("field width in printf format"), STD_C89 },
376 { 'p', 0, 0, N_("precision"), N_("precision in printf format"), STD_C89 },
377 { 'L', 0, 0, N_("length modifier"), N_("length modifier in printf format"), STD_C89 },
378 { 0, 0, 0, NULL, NULL, 0 }
381 static const format_flag_pair asm_fprintf_flag_pairs[] =
385 { '0', 'p', 1, 'i' },
389 static const format_flag_pair gcc_diag_flag_pairs[] =
394 #define gcc_cdiag_flag_pairs gcc_diag_flag_pairs
395 #define gcc_cxxdiag_flag_pairs gcc_diag_flag_pairs
397 static const format_flag_spec gcc_diag_flag_specs[] =
399 { 'q', 0, 0, N_("'q' flag"), N_("the 'q' diagnostic flag"), STD_C89 },
400 { 'p', 0, 0, N_("precision"), N_("precision in printf format"), STD_C89 },
401 { 'L', 0, 0, N_("length modifier"), N_("length modifier in printf format"), STD_C89 },
402 { 0, 0, 0, NULL, NULL, 0 }
405 #define gcc_cdiag_flag_specs gcc_diag_flag_specs
407 static const format_flag_spec gcc_cxxdiag_flag_specs[] =
409 { '+', 0, 0, N_("'+' flag"), N_("the '+' printf flag"), STD_C89 },
410 { '#', 0, 0, N_("'#' flag"), N_("the '#' printf flag"), STD_C89 },
411 { 'q', 0, 0, N_("'q' flag"), N_("the 'q' diagnostic flag"), STD_C89 },
412 { 'p', 0, 0, N_("precision"), N_("precision in printf format"), STD_C89 },
413 { 'L', 0, 0, N_("length modifier"), N_("length modifier in printf format"), STD_C89 },
414 { 0, 0, 0, NULL, NULL, 0 }
417 static const format_flag_spec scanf_flag_specs[] =
419 { '*', 0, 0, N_("assignment suppression"), N_("the assignment suppression scanf feature"), STD_C89 },
420 { 'a', 0, 0, N_("'a' flag"), N_("the 'a' scanf flag"), STD_EXT },
421 { 'w', 0, 0, N_("field width"), N_("field width in scanf format"), STD_C89 },
422 { 'L', 0, 0, N_("length modifier"), N_("length modifier in scanf format"), STD_C89 },
423 { '\'', 0, 0, N_("''' flag"), N_("the ''' scanf flag"), STD_EXT },
424 { 'I', 0, 0, N_("'I' flag"), N_("the 'I' scanf flag"), STD_EXT },
425 { 0, 0, 0, NULL, NULL, 0 }
429 static const format_flag_pair scanf_flag_pairs[] =
436 static const format_flag_spec strftime_flag_specs[] =
438 { '_', 0, 0, N_("'_' flag"), N_("the '_' strftime flag"), STD_EXT },
439 { '-', 0, 0, N_("'-' flag"), N_("the '-' strftime flag"), STD_EXT },
440 { '0', 0, 0, N_("'0' flag"), N_("the '0' strftime flag"), STD_EXT },
441 { '^', 0, 0, N_("'^' flag"), N_("the '^' strftime flag"), STD_EXT },
442 { '#', 0, 0, N_("'#' flag"), N_("the '#' strftime flag"), STD_EXT },
443 { 'w', 0, 0, N_("field width"), N_("field width in strftime format"), STD_EXT },
444 { 'E', 0, 0, N_("'E' modifier"), N_("the 'E' strftime modifier"), STD_C99 },
445 { 'O', 0, 0, N_("'O' modifier"), N_("the 'O' strftime modifier"), STD_C99 },
446 { 'O', 'o', 0, NULL, N_("the 'O' modifier"), STD_EXT },
447 { 0, 0, 0, NULL, NULL, 0 }
451 static const format_flag_pair strftime_flag_pairs[] =
462 static const format_flag_spec strfmon_flag_specs[] =
464 { '=', 0, 1, N_("fill character"), N_("fill character in strfmon format"), STD_C89 },
465 { '^', 0, 0, N_("'^' flag"), N_("the '^' strfmon flag"), STD_C89 },
466 { '+', 0, 0, N_("'+' flag"), N_("the '+' strfmon flag"), STD_C89 },
467 { '(', 0, 0, N_("'(' flag"), N_("the '(' strfmon flag"), STD_C89 },
468 { '!', 0, 0, N_("'!' flag"), N_("the '!' strfmon flag"), STD_C89 },
469 { '-', 0, 0, N_("'-' flag"), N_("the '-' strfmon flag"), STD_C89 },
470 { 'w', 0, 0, N_("field width"), N_("field width in strfmon format"), STD_C89 },
471 { '#', 0, 0, N_("left precision"), N_("left precision in strfmon format"), STD_C89 },
472 { 'p', 0, 0, N_("right precision"), N_("right precision in strfmon format"), STD_C89 },
473 { 'L', 0, 0, N_("length modifier"), N_("length modifier in strfmon format"), STD_C89 },
474 { 0, 0, 0, NULL, NULL, 0 }
477 static const format_flag_pair strfmon_flag_pairs[] =
484 static const format_char_info print_char_table[] =
486 /* C89 conversion specifiers. */
487 { "di", 0, STD_C89, { T89_I, T99_SC, T89_S, T89_L, T9L_LL, TEX_LL, T99_SST, T99_PD, T99_IM }, "-wp0 +'I", "i", NULL },
488 { "oxX", 0, STD_C89, { T89_UI, T99_UC, T89_US, T89_UL, T9L_ULL, TEX_ULL, T99_ST, T99_UPD, T99_UIM }, "-wp0#", "i", NULL },
489 { "u", 0, STD_C89, { T89_UI, T99_UC, T89_US, T89_UL, T9L_ULL, TEX_ULL, T99_ST, T99_UPD, T99_UIM }, "-wp0'I", "i", NULL },
490 { "fgG", 0, STD_C89, { T89_D, BADLEN, BADLEN, T99_D, BADLEN, T89_LD, BADLEN, BADLEN, BADLEN }, "-wp0 +#'I", "", NULL },
491 { "eE", 0, STD_C89, { T89_D, BADLEN, BADLEN, T99_D, BADLEN, T89_LD, BADLEN, BADLEN, BADLEN }, "-wp0 +#I", "", NULL },
492 { "c", 0, STD_C89, { T89_I, BADLEN, BADLEN, T94_WI, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN }, "-w", "", NULL },
493 { "s", 1, STD_C89, { T89_C, BADLEN, BADLEN, T94_W, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN }, "-wp", "cR", NULL },
494 { "p", 1, STD_C89, { T89_V, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN }, "-w", "c", NULL },
495 { "n", 1, STD_C89, { T89_I, T99_SC, T89_S, T89_L, T9L_LL, BADLEN, T99_SST, T99_PD, T99_IM }, "", "W", NULL },
496 /* C99 conversion specifiers. */
497 { "F", 0, STD_C99, { T99_D, BADLEN, BADLEN, T99_D, BADLEN, T99_LD, BADLEN, BADLEN, BADLEN }, "-wp0 +#'I", "", NULL },
498 { "aA", 0, STD_C99, { T99_D, BADLEN, BADLEN, T99_D, BADLEN, T99_LD, BADLEN, BADLEN, BADLEN }, "-wp0 +#", "", NULL },
499 /* X/Open conversion specifiers. */
500 { "C", 0, STD_EXT, { TEX_WI, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN }, "-w", "", NULL },
501 { "S", 1, STD_EXT, { TEX_W, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN }, "-wp", "R", NULL },
502 /* GNU conversion specifiers. */
503 { "m", 0, STD_EXT, { T89_V, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN }, "-wp", "", NULL },
504 { NULL, 0, 0, NOLENGTHS, NULL, NULL, NULL }
507 static const format_char_info asm_fprintf_char_table[] =
509 /* C89 conversion specifiers. */
510 { "di", 0, STD_C89, { T89_I, BADLEN, BADLEN, T89_L, T9L_LL, BADLEN, BADLEN, BADLEN, BADLEN }, "-wp0 +", "i", NULL },
511 { "oxX", 0, STD_C89, { T89_UI, BADLEN, BADLEN, T89_UL, T9L_ULL, BADLEN, BADLEN, BADLEN, BADLEN }, "-wp0#", "i", NULL },
512 { "u", 0, STD_C89, { T89_UI, BADLEN, BADLEN, T89_UL, T9L_ULL, BADLEN, BADLEN, BADLEN, BADLEN }, "-wp0", "i", NULL },
513 { "c", 0, STD_C89, { T89_I, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN }, "-w", "", NULL },
514 { "s", 1, STD_C89, { T89_C, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN }, "-wp", "cR", NULL },
516 /* asm_fprintf conversion specifiers. */
517 { "O", 0, STD_C89, NOARGUMENTS, "", "", NULL },
518 { "R", 0, STD_C89, NOARGUMENTS, "", "", NULL },
519 { "I", 0, STD_C89, NOARGUMENTS, "", "", NULL },
520 { "L", 0, STD_C89, NOARGUMENTS, "", "", NULL },
521 { "U", 0, STD_C89, NOARGUMENTS, "", "", NULL },
522 { "r", 0, STD_C89, { T89_I, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN }, "", "", NULL },
523 { "@", 0, STD_C89, NOARGUMENTS, "", "", NULL },
524 { NULL, 0, 0, NOLENGTHS, NULL, NULL, NULL }
527 static const format_char_info gcc_diag_char_table[] =
529 /* C89 conversion specifiers. */
530 { "di", 0, STD_C89, { T89_I, BADLEN, BADLEN, T89_L, T9L_LL, BADLEN, BADLEN, BADLEN, BADLEN }, "q", "", NULL },
531 { "ox", 0, STD_C89, { T89_UI, BADLEN, BADLEN, T89_UL, T9L_ULL, BADLEN, BADLEN, BADLEN, BADLEN }, "q", "", NULL },
532 { "u", 0, STD_C89, { T89_UI, BADLEN, BADLEN, T89_UL, T9L_ULL, BADLEN, BADLEN, BADLEN, BADLEN }, "q", "", NULL },
533 { "c", 0, STD_C89, { T89_I, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN }, "q", "", NULL },
534 { "s", 1, STD_C89, { T89_C, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN }, "pq", "cR", NULL },
535 { "p", 1, STD_C89, { T89_V, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN }, "q", "c", NULL },
537 /* Custom conversion specifiers. */
539 /* %H will require "location_t" at runtime. */
540 { "H", 0, STD_C89, { T89_V, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN }, "q", "", NULL },
542 /* These will require a "tree" at runtime. */
543 { "J", 0, STD_C89, { T89_V, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN }, "q", "", NULL },
545 { "<>'", 0, STD_C89, NOARGUMENTS, "", "", NULL },
546 { "m", 0, STD_C89, NOARGUMENTS, "q", "", NULL },
547 { NULL, 0, 0, NOLENGTHS, NULL, NULL, NULL }
550 static const format_char_info gcc_cdiag_char_table[] =
552 /* C89 conversion specifiers. */
553 { "di", 0, STD_C89, { T89_I, BADLEN, BADLEN, T89_L, T9L_LL, BADLEN, BADLEN, BADLEN, BADLEN }, "q", "", NULL },
554 { "ox", 0, STD_C89, { T89_UI, BADLEN, BADLEN, T89_UL, T9L_ULL, BADLEN, BADLEN, BADLEN, BADLEN }, "q", "", NULL },
555 { "u", 0, STD_C89, { T89_UI, BADLEN, BADLEN, T89_UL, T9L_ULL, BADLEN, BADLEN, BADLEN, BADLEN }, "q", "", NULL },
556 { "c", 0, STD_C89, { T89_I, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN }, "q", "", NULL },
557 { "s", 1, STD_C89, { T89_C, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN }, "pq", "cR", NULL },
558 { "p", 1, STD_C89, { T89_V, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN }, "q", "c", NULL },
560 /* Custom conversion specifiers. */
562 /* %H will require "location_t" at runtime. */
563 { "H", 0, STD_C89, { T89_V, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN }, "q", "", NULL },
565 /* These will require a "tree" at runtime. */
566 { "DEFJT", 0, STD_C89, { T89_V, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN }, "q", "", NULL },
568 { "<>'", 0, STD_C89, NOARGUMENTS, "", "", NULL },
569 { "m", 0, STD_C89, NOARGUMENTS, "q", "", NULL },
570 { NULL, 0, 0, NOLENGTHS, NULL, NULL, NULL }
573 static const format_char_info gcc_cxxdiag_char_table[] =
575 /* C89 conversion specifiers. */
576 { "di", 0, STD_C89, { T89_I, BADLEN, BADLEN, T89_L, T9L_LL, BADLEN, BADLEN, BADLEN, BADLEN }, "q", "", NULL },
577 { "ox", 0, STD_C89, { T89_UI, BADLEN, BADLEN, T89_UL, T9L_ULL, BADLEN, BADLEN, BADLEN, BADLEN }, "q", "", NULL },
578 { "u", 0, STD_C89, { T89_UI, BADLEN, BADLEN, T89_UL, T9L_ULL, BADLEN, BADLEN, BADLEN, BADLEN }, "q", "", NULL },
579 { "c", 0, STD_C89, { T89_I, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN }, "q", "", NULL },
580 { "s", 1, STD_C89, { T89_C, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN }, "pq", "cR", NULL },
581 { "p", 1, STD_C89, { T89_V, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN }, "q", "c", NULL },
583 /* Custom conversion specifiers. */
585 /* %H will require "location_t" at runtime. */
586 { "H", 0, STD_C89, { T89_V, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN }, "q", "", NULL },
588 /* These will require a "tree" at runtime. */
589 { "ADEFJTV",0,STD_C89,{ T89_V, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN }, "q+#", "", NULL },
591 /* These accept either an 'int' or an 'enum tree_code' (which is handled as an 'int'.) */
592 { "CLOPQ",0,STD_C89, { T89_I, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN }, "q", "", NULL },
594 { "<>'", 0, STD_C89, NOARGUMENTS, "", "", NULL },
595 { "m", 0, STD_C89, NOARGUMENTS, "q", "", NULL },
596 { NULL, 0, 0, NOLENGTHS, NULL, NULL, NULL }
599 static const format_char_info scan_char_table[] =
601 /* C89 conversion specifiers. */
602 { "di", 1, STD_C89, { T89_I, T99_SC, T89_S, T89_L, T9L_LL, TEX_LL, T99_SST, T99_PD, T99_IM }, "*w'I", "W", NULL },
603 { "u", 1, STD_C89, { T89_UI, T99_UC, T89_US, T89_UL, T9L_ULL, TEX_ULL, T99_ST, T99_UPD, T99_UIM }, "*w'I", "W", NULL },
604 { "oxX", 1, STD_C89, { T89_UI, T99_UC, T89_US, T89_UL, T9L_ULL, TEX_ULL, T99_ST, T99_UPD, T99_UIM }, "*w", "W", NULL },
605 { "efgEG", 1, STD_C89, { T89_F, BADLEN, BADLEN, T89_D, BADLEN, T89_LD, BADLEN, BADLEN, BADLEN }, "*w'", "W", NULL },
606 { "c", 1, STD_C89, { T89_C, BADLEN, BADLEN, T94_W, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN }, "*w", "cW", NULL },
607 { "s", 1, STD_C89, { T89_C, BADLEN, BADLEN, T94_W, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN }, "*aw", "cW", NULL },
608 { "[", 1, STD_C89, { T89_C, BADLEN, BADLEN, T94_W, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN }, "*aw", "cW[", NULL },
609 { "p", 2, STD_C89, { T89_V, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN }, "*w", "W", NULL },
610 { "n", 1, STD_C89, { T89_I, T99_SC, T89_S, T89_L, T9L_LL, BADLEN, T99_SST, T99_PD, T99_IM }, "", "W", NULL },
611 /* C99 conversion specifiers. */
612 { "FaA", 1, STD_C99, { T99_F, BADLEN, BADLEN, T99_D, BADLEN, T99_LD, BADLEN, BADLEN, BADLEN }, "*w'", "W", NULL },
613 /* X/Open conversion specifiers. */
614 { "C", 1, STD_EXT, { TEX_W, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN }, "*w", "W", NULL },
615 { "S", 1, STD_EXT, { TEX_W, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN, BADLEN }, "*aw", "W", NULL },
616 { NULL, 0, 0, NOLENGTHS, NULL, NULL, NULL }
619 static const format_char_info time_char_table[] =
621 /* C89 conversion specifiers. */
622 { "ABZab", 0, STD_C89, NOLENGTHS, "^#", "", NULL },
623 { "cx", 0, STD_C89, NOLENGTHS, "E", "3", NULL },
624 { "HIMSUWdmw", 0, STD_C89, NOLENGTHS, "-_0Ow", "", NULL },
625 { "j", 0, STD_C89, NOLENGTHS, "-_0Ow", "o", NULL },
626 { "p", 0, STD_C89, NOLENGTHS, "#", "", NULL },
627 { "X", 0, STD_C89, NOLENGTHS, "E", "", NULL },
628 { "y", 0, STD_C89, NOLENGTHS, "EO-_0w", "4", NULL },
629 { "Y", 0, STD_C89, NOLENGTHS, "-_0EOw", "o", NULL },
630 { "%", 0, STD_C89, NOLENGTHS, "", "", NULL },
631 /* C99 conversion specifiers. */
632 { "C", 0, STD_C99, NOLENGTHS, "-_0EOw", "o", NULL },
633 { "D", 0, STD_C99, NOLENGTHS, "", "2", NULL },
634 { "eVu", 0, STD_C99, NOLENGTHS, "-_0Ow", "", NULL },
635 { "FRTnrt", 0, STD_C99, NOLENGTHS, "", "", NULL },
636 { "g", 0, STD_C99, NOLENGTHS, "O-_0w", "2o", NULL },
637 { "G", 0, STD_C99, NOLENGTHS, "-_0Ow", "o", NULL },
638 { "h", 0, STD_C99, NOLENGTHS, "^#", "", NULL },
639 { "z", 0, STD_C99, NOLENGTHS, "O", "o", NULL },
640 /* GNU conversion specifiers. */
641 { "kls", 0, STD_EXT, NOLENGTHS, "-_0Ow", "", NULL },
642 { "P", 0, STD_EXT, NOLENGTHS, "", "", NULL },
643 { NULL, 0, 0, NOLENGTHS, NULL, NULL, NULL }
646 static const format_char_info monetary_char_table[] =
648 { "in", 0, STD_C89, { T89_D, BADLEN, BADLEN, BADLEN, BADLEN, T89_LD, BADLEN, BADLEN, BADLEN }, "=^+(!-w#p", "", NULL },
649 { NULL, 0, 0, NOLENGTHS, NULL, NULL, NULL }
652 /* This must be in the same order as enum format_type. */
653 static const format_kind_info format_types_orig[] =
655 { "printf", printf_length_specs, print_char_table, " +#0-'I", NULL,
656 printf_flag_specs, printf_flag_pairs,
657 FMT_FLAG_ARG_CONVERT|FMT_FLAG_DOLLAR_MULTIPLE|FMT_FLAG_USE_DOLLAR|FMT_FLAG_EMPTY_PREC_OK,
659 &integer_type_node, &integer_type_node
661 { "asm_fprintf", asm_fprintf_length_specs, asm_fprintf_char_table, " +#0-", NULL,
662 asm_fprintf_flag_specs, asm_fprintf_flag_pairs,
663 FMT_FLAG_ARG_CONVERT|FMT_FLAG_EMPTY_PREC_OK,
667 { "gcc_diag", gcc_diag_length_specs, gcc_diag_char_table, "q", NULL,
668 gcc_diag_flag_specs, gcc_diag_flag_pairs,
669 FMT_FLAG_ARG_CONVERT,
671 NULL, &integer_type_node
673 { "gcc_cdiag", gcc_cdiag_length_specs, gcc_cdiag_char_table, "q", NULL,
674 gcc_cdiag_flag_specs, gcc_cdiag_flag_pairs,
675 FMT_FLAG_ARG_CONVERT,
677 NULL, &integer_type_node
679 { "gcc_cxxdiag", gcc_cxxdiag_length_specs, gcc_cxxdiag_char_table, "q+#", NULL,
680 gcc_cxxdiag_flag_specs, gcc_cxxdiag_flag_pairs,
681 FMT_FLAG_ARG_CONVERT,
683 NULL, &integer_type_node
685 { "scanf", scanf_length_specs, scan_char_table, "*'I", NULL,
686 scanf_flag_specs, scanf_flag_pairs,
687 FMT_FLAG_ARG_CONVERT|FMT_FLAG_SCANF_A_KLUDGE|FMT_FLAG_USE_DOLLAR|FMT_FLAG_ZERO_WIDTH_BAD|FMT_FLAG_DOLLAR_GAP_POINTER_OK,
691 { "strftime", NULL, time_char_table, "_-0^#", "EO",
692 strftime_flag_specs, strftime_flag_pairs,
693 FMT_FLAG_FANCY_PERCENT_OK, 'w', 0, 0, 0, 0,
696 { "strfmon", strfmon_length_specs, monetary_char_table, "=^+(!-", NULL,
697 strfmon_flag_specs, strfmon_flag_pairs,
698 FMT_FLAG_ARG_CONVERT, 'w', '#', 'p', 0, 'L',
703 /* This layer of indirection allows GCC to reassign format_types with
704 new data if necessary, while still allowing the original data to be
706 static const format_kind_info *format_types = format_types_orig;
707 /* We can modify this one. We also add target-specific format types
708 to the end of the array. */
709 static format_kind_info *dynamic_format_types;
711 static int n_format_types = ARRAY_SIZE (format_types_orig);
713 /* Structure detailing the results of checking a format function call
714 where the format expression may be a conditional expression with
715 many leaves resulting from nested conditional expressions. */
718 /* Number of leaves of the format argument that could not be checked
719 as they were not string literals. */
720 int number_non_literal;
721 /* Number of leaves of the format argument that were null pointers or
722 string literals, but had extra format arguments. */
723 int number_extra_args;
724 /* Number of leaves of the format argument that were null pointers or
725 string literals, but had extra format arguments and used $ operand
727 int number_dollar_extra_args;
728 /* Number of leaves of the format argument that were wide string
731 /* Number of leaves of the format argument that were empty strings. */
733 /* Number of leaves of the format argument that were unterminated
735 int number_unterminated;
736 /* Number of leaves of the format argument that were not counted above. */
738 } format_check_results;
742 format_check_results *res;
743 function_format_info *info;
745 } format_check_context;
747 static void check_format_info (function_format_info *, tree);
748 static void check_format_arg (void *, tree, unsigned HOST_WIDE_INT);
749 static void check_format_info_main (format_check_results *,
750 function_format_info *,
751 const char *, int, tree,
752 unsigned HOST_WIDE_INT);
754 static void init_dollar_format_checking (int, tree);
755 static int maybe_read_dollar_number (const char **, int,
756 tree, tree *, const format_kind_info *);
757 static bool avoid_dollar_number (const char *);
758 static void finish_dollar_format_checking (format_check_results *, int);
760 static const format_flag_spec *get_flag_spec (const format_flag_spec *,
763 static void check_format_types (format_wanted_type *, const char *, int);
764 static void format_type_warning (const char *, const char *, int, tree,
765 int, const char *, tree, int);
767 /* Decode a format type from a string, returning the type, or
768 format_type_error if not valid, in which case the caller should print an
771 decode_format_type (const char *s)
776 for (i = 0; i < n_format_types; i++)
779 if (!strcmp (s, format_types[i].name))
781 alen = strlen (format_types[i].name);
782 if (slen == alen + 4 && s[0] == '_' && s[1] == '_'
783 && s[slen - 1] == '_' && s[slen - 2] == '_'
784 && !strncmp (s + 2, format_types[i].name, alen))
787 return format_type_error;
791 /* Check the argument list of a call to printf, scanf, etc.
792 ATTRS are the attributes on the function type.
793 PARAMS is the list of argument values. Also, if -Wmissing-format-attribute,
794 warn for calls to vprintf or vscanf in functions with no such format
795 attribute themselves. */
798 check_function_format (tree attrs, tree params)
802 /* See if this function has any format attributes. */
803 for (a = attrs; a; a = TREE_CHAIN (a))
805 if (is_attribute_p ("format", TREE_PURPOSE (a)))
808 function_format_info info;
809 decode_format_attr (TREE_VALUE (a), &info, 1);
810 check_format_info (&info, params);
811 if (warn_missing_format_attribute && info.first_arg_num == 0
812 && (format_types[info.format_type].flags
813 & (int) FMT_FLAG_ARG_CONVERT))
816 for (c = TYPE_ATTRIBUTES (TREE_TYPE (current_function_decl));
819 if (is_attribute_p ("format", TREE_PURPOSE (c))
820 && (decode_format_type (IDENTIFIER_POINTER
821 (TREE_VALUE (TREE_VALUE (c))))
822 == info.format_type))
826 /* Check if the current function has a parameter to which
827 the format attribute could be attached; if not, it
828 can't be a candidate for a format attribute, despite
829 the vprintf-like or vscanf-like call. */
831 for (args = DECL_ARGUMENTS (current_function_decl);
833 args = TREE_CHAIN (args))
835 if (TREE_CODE (TREE_TYPE (args)) == POINTER_TYPE
836 && (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (args)))
841 warning ("function might be possible candidate for %qs format attribute",
842 format_types[info.format_type].name);
850 /* Variables used by the checking of $ operand number formats. */
851 static char *dollar_arguments_used = NULL;
852 static char *dollar_arguments_pointer_p = NULL;
853 static int dollar_arguments_alloc = 0;
854 static int dollar_arguments_count;
855 static int dollar_first_arg_num;
856 static int dollar_max_arg_used;
857 static int dollar_format_warned;
859 /* Initialize the checking for a format string that may contain $
860 parameter number specifications; we will need to keep track of whether
861 each parameter has been used. FIRST_ARG_NUM is the number of the first
862 argument that is a parameter to the format, or 0 for a vprintf-style
863 function; PARAMS is the list of arguments starting at this argument. */
866 init_dollar_format_checking (int first_arg_num, tree params)
868 tree oparams = params;
870 dollar_first_arg_num = first_arg_num;
871 dollar_arguments_count = 0;
872 dollar_max_arg_used = 0;
873 dollar_format_warned = 0;
874 if (first_arg_num > 0)
878 dollar_arguments_count++;
879 params = TREE_CHAIN (params);
882 if (dollar_arguments_alloc < dollar_arguments_count)
884 if (dollar_arguments_used)
885 free (dollar_arguments_used);
886 if (dollar_arguments_pointer_p)
887 free (dollar_arguments_pointer_p);
888 dollar_arguments_alloc = dollar_arguments_count;
889 dollar_arguments_used = XNEWVEC (char, dollar_arguments_alloc);
890 dollar_arguments_pointer_p = XNEWVEC (char, dollar_arguments_alloc);
892 if (dollar_arguments_alloc)
894 memset (dollar_arguments_used, 0, dollar_arguments_alloc);
895 if (first_arg_num > 0)
901 dollar_arguments_pointer_p[i] = (TREE_CODE (TREE_TYPE (TREE_VALUE (params)))
903 params = TREE_CHAIN (params);
911 /* Look for a decimal number followed by a $ in *FORMAT. If DOLLAR_NEEDED
912 is set, it is an error if one is not found; otherwise, it is OK. If
913 such a number is found, check whether it is within range and mark that
914 numbered operand as being used for later checking. Returns the operand
915 number if found and within range, zero if no such number was found and
916 this is OK, or -1 on error. PARAMS points to the first operand of the
917 format; PARAM_PTR is made to point to the parameter referred to. If
918 a $ format is found, *FORMAT is updated to point just after it. */
921 maybe_read_dollar_number (const char **format,
922 int dollar_needed, tree params, tree *param_ptr,
923 const format_kind_info *fki)
927 const char *fcp = *format;
932 warning ("missing $ operand number in format");
940 while (ISDIGIT (*fcp))
943 nargnum = 10 * argnum + (*fcp - '0');
944 if (nargnum < 0 || nargnum / 10 != argnum)
953 warning ("missing $ operand number in format");
960 if (pedantic && !dollar_format_warned)
962 warning ("%s does not support %%n$ operand number formats",
963 C_STD_NAME (STD_EXT));
964 dollar_format_warned = 1;
966 if (overflow_flag || argnum == 0
967 || (dollar_first_arg_num && argnum > dollar_arguments_count))
969 warning ("operand number out of range in format");
972 if (argnum > dollar_max_arg_used)
973 dollar_max_arg_used = argnum;
974 /* For vprintf-style functions we may need to allocate more memory to
975 track which arguments are used. */
976 while (dollar_arguments_alloc < dollar_max_arg_used)
979 nalloc = 2 * dollar_arguments_alloc + 16;
980 dollar_arguments_used = XRESIZEVEC (char, dollar_arguments_used,
982 dollar_arguments_pointer_p = XRESIZEVEC (char, dollar_arguments_pointer_p,
984 memset (dollar_arguments_used + dollar_arguments_alloc, 0,
985 nalloc - dollar_arguments_alloc);
986 dollar_arguments_alloc = nalloc;
988 if (!(fki->flags & (int) FMT_FLAG_DOLLAR_MULTIPLE)
989 && dollar_arguments_used[argnum - 1] == 1)
991 dollar_arguments_used[argnum - 1] = 2;
992 warning ("format argument %d used more than once in %s format",
996 dollar_arguments_used[argnum - 1] = 1;
997 if (dollar_first_arg_num)
1000 *param_ptr = params;
1001 for (i = 1; i < argnum && *param_ptr != 0; i++)
1002 *param_ptr = TREE_CHAIN (*param_ptr);
1004 /* This case shouldn't be caught here. */
1005 gcc_assert (*param_ptr);
1012 /* Ensure that FORMAT does not start with a decimal number followed by
1013 a $; give a diagnostic and return true if it does, false otherwise. */
1016 avoid_dollar_number (const char *format)
1018 if (!ISDIGIT (*format))
1020 while (ISDIGIT (*format))
1024 warning ("$ operand number used after format without operand number");
1031 /* Finish the checking for a format string that used $ operand number formats
1032 instead of non-$ formats. We check for unused operands before used ones
1033 (a serious error, since the implementation of the format function
1034 can't know what types to pass to va_arg to find the later arguments).
1035 and for unused operands at the end of the format (if we know how many
1036 arguments the format had, so not for vprintf). If there were operand
1037 numbers out of range on a non-vprintf-style format, we won't have reached
1038 here. If POINTER_GAP_OK, unused arguments are OK if all arguments are
1042 finish_dollar_format_checking (format_check_results *res, int pointer_gap_ok)
1045 bool found_pointer_gap = false;
1046 for (i = 0; i < dollar_max_arg_used; i++)
1048 if (!dollar_arguments_used[i])
1050 if (pointer_gap_ok && (dollar_first_arg_num == 0
1051 || dollar_arguments_pointer_p[i]))
1052 found_pointer_gap = true;
1054 warning ("format argument %d unused before used argument %d in $-style format",
1055 i + 1, dollar_max_arg_used);
1058 if (found_pointer_gap
1059 || (dollar_first_arg_num
1060 && dollar_max_arg_used < dollar_arguments_count))
1062 res->number_other--;
1063 res->number_dollar_extra_args++;
1068 /* Retrieve the specification for a format flag. SPEC contains the
1069 specifications for format flags for the applicable kind of format.
1070 FLAG is the flag in question. If PREDICATES is NULL, the basic
1071 spec for that flag must be retrieved and this function aborts if
1072 it cannot be found. If PREDICATES is not NULL, it is a string listing
1073 possible predicates for the spec entry; if an entry predicated on any
1074 of these is found, it is returned, otherwise NULL is returned. */
1076 static const format_flag_spec *
1077 get_flag_spec (const format_flag_spec *spec, int flag, const char *predicates)
1080 for (i = 0; spec[i].flag_char != 0; i++)
1082 if (spec[i].flag_char != flag)
1084 if (predicates != NULL)
1086 if (spec[i].predicate != 0
1087 && strchr (predicates, spec[i].predicate) != 0)
1090 else if (spec[i].predicate == 0)
1093 gcc_assert (predicates);
1098 /* Check the argument list of a call to printf, scanf, etc.
1099 INFO points to the function_format_info structure.
1100 PARAMS is the list of argument values. */
1103 check_format_info (function_format_info *info, tree params)
1105 format_check_context format_ctx;
1106 unsigned HOST_WIDE_INT arg_num;
1108 format_check_results res;
1109 /* Skip to format argument. If the argument isn't available, there's
1110 no work for us to do; prototype checking will catch the problem. */
1111 for (arg_num = 1; ; ++arg_num)
1115 if (arg_num == info->format_num)
1117 params = TREE_CHAIN (params);
1119 format_tree = TREE_VALUE (params);
1120 params = TREE_CHAIN (params);
1121 if (format_tree == 0)
1124 res.number_non_literal = 0;
1125 res.number_extra_args = 0;
1126 res.number_dollar_extra_args = 0;
1127 res.number_wide = 0;
1128 res.number_empty = 0;
1129 res.number_unterminated = 0;
1130 res.number_other = 0;
1132 format_ctx.res = &res;
1133 format_ctx.info = info;
1134 format_ctx.params = params;
1136 check_function_arguments_recurse (check_format_arg, &format_ctx,
1137 format_tree, arg_num);
1139 if (res.number_non_literal > 0)
1141 /* Functions taking a va_list normally pass a non-literal format
1142 string. These functions typically are declared with
1143 first_arg_num == 0, so avoid warning in those cases. */
1144 if (!(format_types[info->format_type].flags & (int) FMT_FLAG_ARG_CONVERT))
1146 /* For strftime-like formats, warn for not checking the format
1147 string; but there are no arguments to check. */
1148 if (warn_format_nonliteral)
1149 warning ("format not a string literal, format string not checked");
1151 else if (info->first_arg_num != 0)
1153 /* If there are no arguments for the format at all, we may have
1154 printf (foo) which is likely to be a security hole. */
1155 while (arg_num + 1 < info->first_arg_num)
1159 params = TREE_CHAIN (params);
1162 if (params == 0 && (warn_format_nonliteral || warn_format_security))
1163 warning ("format not a string literal and no format arguments");
1164 else if (warn_format_nonliteral)
1165 warning ("format not a string literal, argument types not checked");
1169 /* If there were extra arguments to the format, normally warn. However,
1170 the standard does say extra arguments are ignored, so in the specific
1171 case where we have multiple leaves (conditional expressions or
1172 ngettext) allow extra arguments if at least one leaf didn't have extra
1173 arguments, but was otherwise OK (either non-literal or checked OK).
1174 If the format is an empty string, this should be counted similarly to the
1175 case of extra format arguments. */
1176 if (res.number_extra_args > 0 && res.number_non_literal == 0
1177 && res.number_other == 0 && warn_format_extra_args)
1178 warning ("too many arguments for format");
1179 if (res.number_dollar_extra_args > 0 && res.number_non_literal == 0
1180 && res.number_other == 0 && warn_format_extra_args)
1181 warning ("unused arguments in $-style format");
1182 if (res.number_empty > 0 && res.number_non_literal == 0
1183 && res.number_other == 0 && warn_format_zero_length)
1184 warning ("zero-length %s format string",
1185 format_types[info->format_type].name);
1187 if (res.number_wide > 0)
1188 warning ("format is a wide character string");
1190 if (res.number_unterminated > 0)
1191 warning ("unterminated format string");
1194 /* Callback from check_function_arguments_recurse to check a
1195 format string. FORMAT_TREE is the format parameter. ARG_NUM
1196 is the number of the format argument. CTX points to a
1197 format_check_context. */
1200 check_format_arg (void *ctx, tree format_tree,
1201 unsigned HOST_WIDE_INT arg_num)
1203 format_check_context *format_ctx = (format_check_context *) ctx;
1204 format_check_results *res = format_ctx->res;
1205 function_format_info *info = format_ctx->info;
1206 tree params = format_ctx->params;
1209 HOST_WIDE_INT offset;
1210 const char *format_chars;
1211 tree array_size = 0;
1214 if (integer_zerop (format_tree))
1216 /* Skip to first argument to check, so we can see if this format
1217 has any arguments (it shouldn't). */
1218 while (arg_num + 1 < info->first_arg_num)
1222 params = TREE_CHAIN (params);
1227 res->number_other++;
1229 res->number_extra_args++;
1235 if (TREE_CODE (format_tree) == PLUS_EXPR)
1239 arg0 = TREE_OPERAND (format_tree, 0);
1240 arg1 = TREE_OPERAND (format_tree, 1);
1243 if (TREE_CODE (arg1) == INTEGER_CST)
1245 else if (TREE_CODE (arg0) == INTEGER_CST)
1252 res->number_non_literal++;
1255 if (!host_integerp (arg1, 0)
1256 || (offset = tree_low_cst (arg1, 0)) < 0)
1258 res->number_non_literal++;
1262 if (TREE_CODE (format_tree) != ADDR_EXPR)
1264 res->number_non_literal++;
1267 format_tree = TREE_OPERAND (format_tree, 0);
1268 if (TREE_CODE (format_tree) == VAR_DECL
1269 && TREE_CODE (TREE_TYPE (format_tree)) == ARRAY_TYPE
1270 && (array_init = decl_constant_value (format_tree)) != format_tree
1271 && TREE_CODE (array_init) == STRING_CST)
1273 /* Extract the string constant initializer. Note that this may include
1274 a trailing NUL character that is not in the array (e.g.
1275 const char a[3] = "foo";). */
1276 array_size = DECL_SIZE_UNIT (format_tree);
1277 format_tree = array_init;
1279 if (TREE_CODE (format_tree) != STRING_CST)
1281 res->number_non_literal++;
1284 if (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (format_tree))) != char_type_node)
1289 format_chars = TREE_STRING_POINTER (format_tree);
1290 format_length = TREE_STRING_LENGTH (format_tree);
1291 if (array_size != 0)
1293 /* Variable length arrays can't be initialized. */
1294 gcc_assert (TREE_CODE (array_size) == INTEGER_CST);
1296 if (host_integerp (array_size, 0))
1298 HOST_WIDE_INT array_size_value = TREE_INT_CST_LOW (array_size);
1299 if (array_size_value > 0
1300 && array_size_value == (int) array_size_value
1301 && format_length > array_size_value)
1302 format_length = array_size_value;
1307 if (offset >= format_length)
1309 res->number_non_literal++;
1312 format_chars += offset;
1313 format_length -= offset;
1315 if (format_length < 1)
1317 res->number_unterminated++;
1320 if (format_length == 1)
1322 res->number_empty++;
1325 if (format_chars[--format_length] != 0)
1327 res->number_unterminated++;
1331 /* Skip to first argument to check. */
1332 while (arg_num + 1 < info->first_arg_num)
1336 params = TREE_CHAIN (params);
1339 /* Provisionally increment res->number_other; check_format_info_main
1340 will decrement it if it finds there are extra arguments, but this way
1341 need not adjust it for every return. */
1342 res->number_other++;
1343 check_format_info_main (res, info, format_chars, format_length,
1348 /* Do the main part of checking a call to a format function. FORMAT_CHARS
1349 is the NUL-terminated format string (which at this point may contain
1350 internal NUL characters); FORMAT_LENGTH is its length (excluding the
1351 terminating NUL character). ARG_NUM is one less than the number of
1352 the first format argument to check; PARAMS points to that format
1353 argument in the list of arguments. */
1356 check_format_info_main (format_check_results *res,
1357 function_format_info *info, const char *format_chars,
1358 int format_length, tree params,
1359 unsigned HOST_WIDE_INT arg_num)
1361 const char *orig_format_chars = format_chars;
1362 tree first_fillin_param = params;
1364 const format_kind_info *fki = &format_types[info->format_type];
1365 const format_flag_spec *flag_specs = fki->flag_specs;
1366 const format_flag_pair *bad_flag_pairs = fki->bad_flag_pairs;
1368 /* -1 if no conversions taking an operand have been found; 0 if one has
1369 and it didn't use $; 1 if $ formats are in use. */
1370 int has_operand_number = -1;
1372 init_dollar_format_checking (info->first_arg_num, first_fillin_param);
1377 int suppressed = FALSE;
1378 const char *length_chars = NULL;
1379 enum format_lengths length_chars_val = FMT_LEN_none;
1380 enum format_std_version length_chars_std = STD_C89;
1384 int main_arg_num = 0;
1385 tree main_arg_params = 0;
1386 enum format_std_version wanted_type_std;
1387 const char *wanted_type_name;
1388 format_wanted_type width_wanted_type;
1389 format_wanted_type precision_wanted_type;
1390 format_wanted_type main_wanted_type;
1391 format_wanted_type *first_wanted_type = NULL;
1392 format_wanted_type *last_wanted_type = NULL;
1393 const format_length_info *fli = NULL;
1394 const format_char_info *fci = NULL;
1395 char flag_chars[256];
1397 const char *format_start = format_chars;
1398 if (*format_chars == 0)
1400 if (format_chars - orig_format_chars != format_length)
1401 warning ("embedded %<\\0%> in format");
1402 if (info->first_arg_num != 0 && params != 0
1403 && has_operand_number <= 0)
1405 res->number_other--;
1406 res->number_extra_args++;
1408 if (has_operand_number > 0)
1409 finish_dollar_format_checking (res, fki->flags & (int) FMT_FLAG_DOLLAR_GAP_POINTER_OK);
1412 if (*format_chars++ != '%')
1414 if (*format_chars == 0)
1416 warning ("spurious trailing %<%%%> in format");
1419 if (*format_chars == '%')
1426 if ((fki->flags & (int) FMT_FLAG_USE_DOLLAR) && has_operand_number != 0)
1428 /* Possibly read a $ operand number at the start of the format.
1429 If one was previously used, one is required here. If one
1430 is not used here, we can't immediately conclude this is a
1431 format without them, since it could be printf %m or scanf %*. */
1433 opnum = maybe_read_dollar_number (&format_chars, 0,
1435 &main_arg_params, fki);
1440 has_operand_number = 1;
1441 main_arg_num = opnum + info->first_arg_num - 1;
1444 else if (fki->flags & FMT_FLAG_USE_DOLLAR)
1446 if (avoid_dollar_number (format_chars))
1450 /* Read any format flags, but do not yet validate them beyond removing
1451 duplicates, since in general validation depends on the rest of
1453 while (*format_chars != 0
1454 && strchr (fki->flag_chars, *format_chars) != 0)
1456 const format_flag_spec *s = get_flag_spec (flag_specs,
1457 *format_chars, NULL);
1458 if (strchr (flag_chars, *format_chars) != 0)
1460 warning ("repeated %s in format", _(s->name));
1464 i = strlen (flag_chars);
1465 flag_chars[i++] = *format_chars;
1468 if (s->skip_next_char)
1471 if (*format_chars == 0)
1473 warning ("missing fill character at end of strfmon format");
1480 /* Read any format width, possibly * or *m$. */
1481 if (fki->width_char != 0)
1483 if (fki->width_type != NULL && *format_chars == '*')
1485 i = strlen (flag_chars);
1486 flag_chars[i++] = fki->width_char;
1488 /* "...a field width...may be indicated by an asterisk.
1489 In this case, an int argument supplies the field width..." */
1491 if (has_operand_number != 0)
1494 opnum = maybe_read_dollar_number (&format_chars,
1495 has_operand_number == 1,
1502 has_operand_number = 1;
1503 arg_num = opnum + info->first_arg_num - 1;
1506 has_operand_number = 0;
1510 if (avoid_dollar_number (format_chars))
1513 if (info->first_arg_num != 0)
1517 warning ("too few arguments for format");
1520 cur_param = TREE_VALUE (params);
1521 if (has_operand_number <= 0)
1523 params = TREE_CHAIN (params);
1526 width_wanted_type.wanted_type = *fki->width_type;
1527 width_wanted_type.wanted_type_name = NULL;
1528 width_wanted_type.pointer_count = 0;
1529 width_wanted_type.char_lenient_flag = 0;
1530 width_wanted_type.writing_in_flag = 0;
1531 width_wanted_type.reading_from_flag = 0;
1532 width_wanted_type.name = _("field width");
1533 width_wanted_type.param = cur_param;
1534 width_wanted_type.arg_num = arg_num;
1535 width_wanted_type.next = NULL;
1536 if (last_wanted_type != 0)
1537 last_wanted_type->next = &width_wanted_type;
1538 if (first_wanted_type == 0)
1539 first_wanted_type = &width_wanted_type;
1540 last_wanted_type = &width_wanted_type;
1545 /* Possibly read a numeric width. If the width is zero,
1546 we complain if appropriate. */
1547 int non_zero_width_char = FALSE;
1548 int found_width = FALSE;
1549 while (ISDIGIT (*format_chars))
1552 if (*format_chars != '0')
1553 non_zero_width_char = TRUE;
1556 if (found_width && !non_zero_width_char &&
1557 (fki->flags & (int) FMT_FLAG_ZERO_WIDTH_BAD))
1558 warning ("zero width in %s format", fki->name);
1561 i = strlen (flag_chars);
1562 flag_chars[i++] = fki->width_char;
1568 /* Read any format left precision (must be a number, not *). */
1569 if (fki->left_precision_char != 0 && *format_chars == '#')
1572 i = strlen (flag_chars);
1573 flag_chars[i++] = fki->left_precision_char;
1575 if (!ISDIGIT (*format_chars))
1576 warning ("empty left precision in %s format", fki->name);
1577 while (ISDIGIT (*format_chars))
1581 /* Read any format precision, possibly * or *m$. */
1582 if (fki->precision_char != 0 && *format_chars == '.')
1585 i = strlen (flag_chars);
1586 flag_chars[i++] = fki->precision_char;
1588 if (fki->precision_type != NULL && *format_chars == '*')
1590 /* "...a...precision...may be indicated by an asterisk.
1591 In this case, an int argument supplies the...precision." */
1593 if (has_operand_number != 0)
1596 opnum = maybe_read_dollar_number (&format_chars,
1597 has_operand_number == 1,
1604 has_operand_number = 1;
1605 arg_num = opnum + info->first_arg_num - 1;
1608 has_operand_number = 0;
1612 if (avoid_dollar_number (format_chars))
1615 if (info->first_arg_num != 0)
1619 warning ("too few arguments for format");
1622 cur_param = TREE_VALUE (params);
1623 if (has_operand_number <= 0)
1625 params = TREE_CHAIN (params);
1628 precision_wanted_type.wanted_type = *fki->precision_type;
1629 precision_wanted_type.wanted_type_name = NULL;
1630 precision_wanted_type.pointer_count = 0;
1631 precision_wanted_type.char_lenient_flag = 0;
1632 precision_wanted_type.writing_in_flag = 0;
1633 precision_wanted_type.reading_from_flag = 0;
1634 precision_wanted_type.name = _("field precision");
1635 precision_wanted_type.param = cur_param;
1636 precision_wanted_type.arg_num = arg_num;
1637 precision_wanted_type.next = NULL;
1638 if (last_wanted_type != 0)
1639 last_wanted_type->next = &precision_wanted_type;
1640 if (first_wanted_type == 0)
1641 first_wanted_type = &precision_wanted_type;
1642 last_wanted_type = &precision_wanted_type;
1647 if (!(fki->flags & (int) FMT_FLAG_EMPTY_PREC_OK)
1648 && !ISDIGIT (*format_chars))
1649 warning ("empty precision in %s format", fki->name);
1650 while (ISDIGIT (*format_chars))
1655 /* Read any length modifier, if this kind of format has them. */
1656 fli = fki->length_char_specs;
1657 length_chars = NULL;
1658 length_chars_val = FMT_LEN_none;
1659 length_chars_std = STD_C89;
1662 while (fli->name != 0 && fli->name[0] != *format_chars)
1667 if (fli->double_name != 0 && fli->name[0] == *format_chars)
1670 length_chars = fli->double_name;
1671 length_chars_val = fli->double_index;
1672 length_chars_std = fli->double_std;
1676 length_chars = fli->name;
1677 length_chars_val = fli->index;
1678 length_chars_std = fli->std;
1680 i = strlen (flag_chars);
1681 flag_chars[i++] = fki->length_code_char;
1686 /* Warn if the length modifier is non-standard. */
1687 if (ADJ_STD (length_chars_std) > C_STD_VER)
1688 warning ("%s does not support the %qs %s length modifier",
1689 C_STD_NAME (length_chars_std), length_chars,
1694 /* Read any modifier (strftime E/O). */
1695 if (fki->modifier_chars != NULL)
1697 while (*format_chars != 0
1698 && strchr (fki->modifier_chars, *format_chars) != 0)
1700 if (strchr (flag_chars, *format_chars) != 0)
1702 const format_flag_spec *s = get_flag_spec (flag_specs,
1703 *format_chars, NULL);
1704 warning ("repeated %s in format", _(s->name));
1708 i = strlen (flag_chars);
1709 flag_chars[i++] = *format_chars;
1716 /* Handle the scanf allocation kludge. */
1717 if (fki->flags & (int) FMT_FLAG_SCANF_A_KLUDGE)
1719 if (*format_chars == 'a' && !flag_isoc99)
1721 if (format_chars[1] == 's' || format_chars[1] == 'S'
1722 || format_chars[1] == '[')
1724 /* 'a' is used as a flag. */
1725 i = strlen (flag_chars);
1726 flag_chars[i++] = 'a';
1733 format_char = *format_chars;
1734 if (format_char == 0
1735 || (!(fki->flags & (int) FMT_FLAG_FANCY_PERCENT_OK)
1736 && format_char == '%'))
1738 warning ("conversion lacks type at end of format");
1742 fci = fki->conversion_specs;
1743 while (fci->format_chars != 0
1744 && strchr (fci->format_chars, format_char) == 0)
1746 if (fci->format_chars == 0)
1748 if (ISGRAPH (format_char))
1749 warning ("unknown conversion type character %qc in format",
1752 warning ("unknown conversion type character 0x%x in format",
1758 if (ADJ_STD (fci->std) > C_STD_VER)
1759 warning ("%s does not support the %<%%%c%> %s format",
1760 C_STD_NAME (fci->std), format_char, fki->name);
1763 /* Validate the individual flags used, removing any that are invalid. */
1766 for (i = 0; flag_chars[i] != 0; i++)
1768 const format_flag_spec *s = get_flag_spec (flag_specs,
1769 flag_chars[i], NULL);
1770 flag_chars[i - d] = flag_chars[i];
1771 if (flag_chars[i] == fki->length_code_char)
1773 if (strchr (fci->flag_chars, flag_chars[i]) == 0)
1775 warning ("%s used with %<%%%c%> %s format",
1776 _(s->name), format_char, fki->name);
1782 const format_flag_spec *t;
1783 if (ADJ_STD (s->std) > C_STD_VER)
1784 warning ("%s does not support %s",
1785 C_STD_NAME (s->std), _(s->long_name));
1786 t = get_flag_spec (flag_specs, flag_chars[i], fci->flags2);
1787 if (t != NULL && ADJ_STD (t->std) > ADJ_STD (s->std))
1789 const char *long_name = (t->long_name != NULL
1792 if (ADJ_STD (t->std) > C_STD_VER)
1793 warning ("%s does not support %s with the %<%%%c%> %s format",
1794 C_STD_NAME (t->std), _(long_name),
1795 format_char, fki->name);
1799 flag_chars[i - d] = 0;
1802 if ((fki->flags & (int) FMT_FLAG_SCANF_A_KLUDGE)
1803 && strchr (flag_chars, 'a') != 0)
1806 if (fki->suppression_char
1807 && strchr (flag_chars, fki->suppression_char) != 0)
1810 /* Validate the pairs of flags used. */
1811 for (i = 0; bad_flag_pairs[i].flag_char1 != 0; i++)
1813 const format_flag_spec *s, *t;
1814 if (strchr (flag_chars, bad_flag_pairs[i].flag_char1) == 0)
1816 if (strchr (flag_chars, bad_flag_pairs[i].flag_char2) == 0)
1818 if (bad_flag_pairs[i].predicate != 0
1819 && strchr (fci->flags2, bad_flag_pairs[i].predicate) == 0)
1821 s = get_flag_spec (flag_specs, bad_flag_pairs[i].flag_char1, NULL);
1822 t = get_flag_spec (flag_specs, bad_flag_pairs[i].flag_char2, NULL);
1823 if (bad_flag_pairs[i].ignored)
1825 if (bad_flag_pairs[i].predicate != 0)
1826 warning ("%s ignored with %s and %<%%%c%> %s format",
1827 _(s->name), _(t->name), format_char,
1830 warning ("%s ignored with %s in %s format",
1831 _(s->name), _(t->name), fki->name);
1835 if (bad_flag_pairs[i].predicate != 0)
1836 warning ("use of %s and %s together with %<%%%c%> %s format",
1837 _(s->name), _(t->name), format_char,
1840 warning ("use of %s and %s together in %s format",
1841 _(s->name), _(t->name), fki->name);
1845 /* Give Y2K warnings. */
1846 if (warn_format_y2k)
1849 if (strchr (fci->flags2, '4') != 0)
1850 if (strchr (flag_chars, 'E') != 0)
1854 else if (strchr (fci->flags2, '3') != 0)
1856 else if (strchr (fci->flags2, '2') != 0)
1859 warning ("%<%%%c%> yields only last 2 digits of year in some locales",
1861 else if (y2k_level == 2)
1862 warning ("%<%%%c%> yields only last 2 digits of year", format_char);
1865 if (strchr (fci->flags2, '[') != 0)
1867 /* Skip over scan set, in case it happens to have '%' in it. */
1868 if (*format_chars == '^')
1870 /* Find closing bracket; if one is hit immediately, then
1871 it's part of the scan set rather than a terminator. */
1872 if (*format_chars == ']')
1874 while (*format_chars && *format_chars != ']')
1876 if (*format_chars != ']')
1877 /* The end of the format string was reached. */
1878 warning ("no closing %<]%> for %<%%[%> format");
1882 wanted_type_name = 0;
1883 if (fki->flags & (int) FMT_FLAG_ARG_CONVERT)
1885 wanted_type = (fci->types[length_chars_val].type
1886 ? *fci->types[length_chars_val].type : 0);
1887 wanted_type_name = fci->types[length_chars_val].name;
1888 wanted_type_std = fci->types[length_chars_val].std;
1889 if (wanted_type == 0)
1891 warning ("use of %qs length modifier with %qc type character",
1892 length_chars, format_char);
1893 /* Heuristic: skip one argument when an invalid length/type
1894 combination is encountered. */
1898 warning ("too few arguments for format");
1901 params = TREE_CHAIN (params);
1905 /* Warn if non-standard, provided it is more non-standard
1906 than the length and type characters that may already
1907 have been warned for. */
1908 && ADJ_STD (wanted_type_std) > ADJ_STD (length_chars_std)
1909 && ADJ_STD (wanted_type_std) > ADJ_STD (fci->std))
1911 if (ADJ_STD (wanted_type_std) > C_STD_VER)
1912 warning ("%s does not support the %<%%%s%c%> %s format",
1913 C_STD_NAME (wanted_type_std), length_chars,
1914 format_char, fki->name);
1918 main_wanted_type.next = NULL;
1920 /* Finally. . .check type of argument against desired type! */
1921 if (info->first_arg_num == 0)
1923 if ((fci->pointer_count == 0 && wanted_type == void_type_node)
1926 if (main_arg_num != 0)
1929 warning ("operand number specified with suppressed assignment");
1931 warning ("operand number specified for format taking no argument");
1936 format_wanted_type *wanted_type_ptr;
1938 if (main_arg_num != 0)
1940 arg_num = main_arg_num;
1941 params = main_arg_params;
1946 if (has_operand_number > 0)
1948 warning ("missing $ operand number in format");
1952 has_operand_number = 0;
1955 wanted_type_ptr = &main_wanted_type;
1960 warning ("too few arguments for format");
1964 cur_param = TREE_VALUE (params);
1965 params = TREE_CHAIN (params);
1967 wanted_type_ptr->wanted_type = wanted_type;
1968 wanted_type_ptr->wanted_type_name = wanted_type_name;
1969 wanted_type_ptr->pointer_count = fci->pointer_count + aflag;
1970 wanted_type_ptr->char_lenient_flag = 0;
1971 if (strchr (fci->flags2, 'c') != 0)
1972 wanted_type_ptr->char_lenient_flag = 1;
1973 wanted_type_ptr->writing_in_flag = 0;
1974 wanted_type_ptr->reading_from_flag = 0;
1976 wanted_type_ptr->writing_in_flag = 1;
1979 if (strchr (fci->flags2, 'W') != 0)
1980 wanted_type_ptr->writing_in_flag = 1;
1981 if (strchr (fci->flags2, 'R') != 0)
1982 wanted_type_ptr->reading_from_flag = 1;
1984 wanted_type_ptr->name = NULL;
1985 wanted_type_ptr->param = cur_param;
1986 wanted_type_ptr->arg_num = arg_num;
1987 wanted_type_ptr->next = NULL;
1988 if (last_wanted_type != 0)
1989 last_wanted_type->next = wanted_type_ptr;
1990 if (first_wanted_type == 0)
1991 first_wanted_type = wanted_type_ptr;
1992 last_wanted_type = wanted_type_ptr;
1997 wanted_type_ptr = ggc_alloc (sizeof (main_wanted_type));
1999 wanted_type = *fci->types[length_chars_val].type;
2000 wanted_type_name = fci->types[length_chars_val].name;
2005 if (first_wanted_type != 0)
2006 check_format_types (first_wanted_type, format_start,
2007 format_chars - format_start);
2009 if (main_wanted_type.next != NULL)
2011 format_wanted_type *wanted_type_ptr = main_wanted_type.next;
2012 while (wanted_type_ptr)
2014 format_wanted_type *next = wanted_type_ptr->next;
2015 ggc_free (wanted_type_ptr);
2016 wanted_type_ptr = next;
2023 /* Check the argument types from a single format conversion (possibly
2024 including width and precision arguments). */
2026 check_format_types (format_wanted_type *types, const char *format_start,
2029 for (; types != 0; types = types->next)
2038 cur_param = types->param;
2039 cur_type = TREE_TYPE (cur_param);
2040 if (cur_type == error_mark_node)
2042 orig_cur_type = cur_type;
2044 wanted_type = types->wanted_type;
2045 arg_num = types->arg_num;
2047 /* The following should not occur here. */
2048 gcc_assert (wanted_type);
2049 gcc_assert (wanted_type != void_type_node || types->pointer_count);
2051 if (types->pointer_count == 0)
2052 wanted_type = lang_hooks.types.type_promotes_to (wanted_type);
2054 wanted_type = TYPE_MAIN_VARIANT (wanted_type);
2056 STRIP_NOPS (cur_param);
2058 /* Check the types of any additional pointer arguments
2059 that precede the "real" argument. */
2060 for (i = 0; i < types->pointer_count; ++i)
2062 if (TREE_CODE (cur_type) == POINTER_TYPE)
2064 cur_type = TREE_TYPE (cur_type);
2065 if (cur_type == error_mark_node)
2068 /* Check for writing through a NULL pointer. */
2069 if (types->writing_in_flag
2072 && integer_zerop (cur_param))
2073 warning ("writing through null pointer (argument %d)",
2076 /* Check for reading through a NULL pointer. */
2077 if (types->reading_from_flag
2080 && integer_zerop (cur_param))
2081 warning ("reading through null pointer (argument %d)",
2084 if (cur_param != 0 && TREE_CODE (cur_param) == ADDR_EXPR)
2085 cur_param = TREE_OPERAND (cur_param, 0);
2089 /* See if this is an attempt to write into a const type with
2090 scanf or with printf "%n". Note: the writing in happens
2091 at the first indirection only, if for example
2092 void * const * is passed to scanf %p; passing
2093 const void ** is simply passing an incompatible type. */
2094 if (types->writing_in_flag
2096 && (TYPE_READONLY (cur_type)
2098 && (CONSTANT_CLASS_P (cur_param)
2099 || (DECL_P (cur_param)
2100 && TREE_READONLY (cur_param))))))
2101 warning ("writing into constant object (argument %d)",
2104 /* If there are extra type qualifiers beyond the first
2105 indirection, then this makes the types technically
2109 && (TYPE_READONLY (cur_type)
2110 || TYPE_VOLATILE (cur_type)
2111 || TYPE_RESTRICT (cur_type)))
2112 warning ("extra type qualifiers in format argument "
2119 format_type_warning (types->name, format_start, format_length,
2120 wanted_type, types->pointer_count,
2121 types->wanted_type_name, orig_cur_type,
2127 if (i < types->pointer_count)
2130 cur_type = TYPE_MAIN_VARIANT (cur_type);
2132 /* Check whether the argument type is a character type. This leniency
2133 only applies to certain formats, flagged with 'c'.
2135 if (types->char_lenient_flag)
2136 char_type_flag = (cur_type == char_type_node
2137 || cur_type == signed_char_type_node
2138 || cur_type == unsigned_char_type_node);
2140 /* Check the type of the "real" argument, if there's a type we want. */
2141 if (wanted_type == cur_type)
2143 /* If we want 'void *', allow any pointer type.
2144 (Anything else would already have got a warning.)
2145 With -pedantic, only allow pointers to void and to character
2147 if (wanted_type == void_type_node
2148 && (!pedantic || (i == 1 && char_type_flag)))
2150 /* Don't warn about differences merely in signedness, unless
2151 -pedantic. With -pedantic, warn if the type is a pointer
2152 target and not a character type, and for character types at
2153 a second level of indirection. */
2154 if (TREE_CODE (wanted_type) == INTEGER_TYPE
2155 && TREE_CODE (cur_type) == INTEGER_TYPE
2156 && (!pedantic || i == 0 || (i == 1 && char_type_flag))
2157 && (TYPE_UNSIGNED (wanted_type)
2158 ? wanted_type == c_common_unsigned_type (cur_type)
2159 : wanted_type == c_common_signed_type (cur_type)))
2161 /* Likewise, "signed char", "unsigned char" and "char" are
2162 equivalent but the above test won't consider them equivalent. */
2163 if (wanted_type == char_type_node
2164 && (!pedantic || i < 2)
2167 /* Now we have a type mismatch. */
2168 format_type_warning (types->name, format_start, format_length,
2169 wanted_type, types->pointer_count,
2170 types->wanted_type_name, orig_cur_type, arg_num);
2175 /* Give a warning about a format argument of different type from that
2176 expected. DESCR is a description such as "field precision", or
2177 NULL for an ordinary format. For an ordinary format, FORMAT_START
2178 points to where the format starts in the format string and
2179 FORMAT_LENGTH is its length. WANTED_TYPE is the type the argument
2180 should have after POINTER_COUNT pointer dereferences.
2181 WANTED_NAME_NAME is a possibly more friendly name of WANTED_TYPE,
2182 or NULL if the ordinary name of the type should be used. ARG_TYPE
2183 is the type of the actual argument. ARG_NUM is the number of that
2186 format_type_warning (const char *descr, const char *format_start,
2187 int format_length, tree wanted_type, int pointer_count,
2188 const char *wanted_type_name, tree arg_type, int arg_num)
2191 /* If ARG_TYPE is a typedef with a misleading name (for example,
2192 size_t but not the standard size_t expected by printf %zu), avoid
2193 printing the typedef name. */
2194 if (wanted_type_name
2195 && TYPE_NAME (arg_type)
2196 && TREE_CODE (TYPE_NAME (arg_type)) == TYPE_DECL
2197 && DECL_NAME (TYPE_NAME (arg_type))
2198 && !strcmp (wanted_type_name,
2199 lang_hooks.decl_printable_name (TYPE_NAME (arg_type), 2)))
2200 arg_type = TYPE_MAIN_VARIANT (arg_type);
2201 /* The format type and name exclude any '*' for pointers, so those
2202 must be formatted manually. For all the types we currently have,
2203 this is adequate, but formats taking pointers to functions or
2204 arrays would require the full type to be built up in order to
2205 print it with %T. */
2206 p = alloca (pointer_count + 2);
2207 if (pointer_count == 0)
2209 else if (c_dialect_cxx ())
2211 memset (p, '*', pointer_count);
2212 p[pointer_count] = 0;
2217 memset (p + 1, '*', pointer_count);
2218 p[pointer_count + 1] = 0;
2220 if (wanted_type_name)
2223 warning ("%s should have type %<%s%s%>, but argument %d has type %qT",
2224 descr, wanted_type_name, p, arg_num, arg_type);
2226 warning ("format %q.*s expects type %<%s%s%>, but argument %d has type %qT",
2227 format_length, format_start, wanted_type_name, p,
2233 warning ("%s should have type %<%T%s%>, but argument %d has type %qT",
2234 descr, wanted_type, p, arg_num, arg_type);
2236 warning ("format %q.*s expects type %<%T%s%>, but argument %d has type %qT",
2237 format_length, format_start, wanted_type, p, arg_num, arg_type);
2242 /* Given a format_char_info array FCI, and a character C, this function
2243 returns the index into the conversion_specs where that specifier's
2244 data is located. If the character isn't found it aborts. */
2246 find_char_info_specifier_index (const format_char_info *fci, int c)
2250 for (i = 0; fci->format_chars; i++, fci++)
2251 if (strchr (fci->format_chars, c))
2254 /* We shouldn't be looking for a non-existent specifier. */
2258 /* Given a format_length_info array FLI, and a character C, this
2259 function returns the index into the conversion_specs where that
2260 modifier's data is located. If the character isn't found it
2263 find_length_info_modifier_index (const format_length_info *fli, int c)
2267 for (i = 0; fli->name; i++, fli++)
2268 if (strchr (fli->name, c))
2271 /* We shouldn't be looking for a non-existent modifier. */
2275 /* Determine the type of HOST_WIDE_INT in the code being compiled for
2276 use in GCC's __asm_fprintf__ custom format attribute. You must
2277 have set dynamic_format_types before calling this function. */
2279 init_dynamic_asm_fprintf_info (void)
2285 format_length_info *new_asm_fprintf_length_specs;
2288 /* Find the underlying type for HOST_WIDE_INT. For the %w
2289 length modifier to work, one must have issued: "typedef
2290 HOST_WIDE_INT __gcc_host_wide_int__;" in one's source code
2291 prior to using that modifier. */
2292 hwi = maybe_get_identifier ("__gcc_host_wide_int__");
2294 hwi = DECL_ORIGINAL_TYPE (identifier_global_value (hwi));
2297 /* Create a new (writable) copy of asm_fprintf_length_specs. */
2298 new_asm_fprintf_length_specs = (format_length_info *)
2299 xmemdup (asm_fprintf_length_specs,
2300 sizeof (asm_fprintf_length_specs),
2301 sizeof (asm_fprintf_length_specs));
2303 /* HOST_WIDE_INT must be one of 'long' or 'long long'. */
2304 i = find_length_info_modifier_index (new_asm_fprintf_length_specs, 'w');
2305 if (hwi == long_integer_type_node)
2306 new_asm_fprintf_length_specs[i].index = FMT_LEN_l;
2307 else if (hwi == long_long_integer_type_node)
2308 new_asm_fprintf_length_specs[i].index = FMT_LEN_ll;
2312 /* Assign the new data for use. */
2313 dynamic_format_types[asm_fprintf_format_type].length_char_specs =
2314 new_asm_fprintf_length_specs;
2318 /* Determine the types of "tree" and "location_t" in the code being
2319 compiled for use in GCC's diagnostic custom format attributes. You
2320 must have set dynamic_format_types before calling this function. */
2322 init_dynamic_diag_info (void)
2324 static tree t, loc, hwi;
2326 if (!loc || !t || !hwi)
2328 static format_char_info *diag_fci, *cdiag_fci, *cxxdiag_fci;
2329 static format_length_info *diag_ls;
2332 /* For the GCC-diagnostics custom format specifiers to work, one
2333 must have declared 'tree' and/or 'location_t' prior to using
2334 those attributes. If we haven't seen these declarations then
2335 you shouldn't use the specifiers requiring these types.
2336 However we don't force a hard ICE because we may see only one
2337 or the other type. */
2338 if ((loc = maybe_get_identifier ("location_t")))
2339 loc = TREE_TYPE (identifier_global_value (loc));
2341 /* We need to grab the underlying 'union tree_node' so peek into
2342 an extra type level. */
2343 if ((t = maybe_get_identifier ("tree")))
2344 t = TREE_TYPE (TREE_TYPE (identifier_global_value (t)));
2346 /* Find the underlying type for HOST_WIDE_INT. For the %w
2347 length modifier to work, one must have issued: "typedef
2348 HOST_WIDE_INT __gcc_host_wide_int__;" in one's source code
2349 prior to using that modifier. */
2350 if ((hwi = maybe_get_identifier ("__gcc_host_wide_int__")))
2351 hwi = DECL_ORIGINAL_TYPE (identifier_global_value (hwi));
2353 /* Assign the new data for use. */
2355 /* All the GCC diag formats use the same length specs. */
2357 dynamic_format_types[gcc_diag_format_type].length_char_specs =
2358 dynamic_format_types[gcc_cdiag_format_type].length_char_specs =
2359 dynamic_format_types[gcc_cxxdiag_format_type].length_char_specs =
2360 diag_ls = (format_length_info *)
2361 xmemdup (gcc_diag_length_specs,
2362 sizeof (gcc_diag_length_specs),
2363 sizeof (gcc_diag_length_specs));
2366 /* HOST_WIDE_INT must be one of 'long' or 'long long'. */
2367 i = find_length_info_modifier_index (diag_ls, 'w');
2368 if (hwi == long_integer_type_node)
2369 diag_ls[i].index = FMT_LEN_l;
2370 else if (hwi == long_long_integer_type_node)
2371 diag_ls[i].index = FMT_LEN_ll;
2376 /* Handle the __gcc_diag__ format specifics. */
2378 dynamic_format_types[gcc_diag_format_type].conversion_specs =
2379 diag_fci = (format_char_info *)
2380 xmemdup (gcc_diag_char_table,
2381 sizeof (gcc_diag_char_table),
2382 sizeof (gcc_diag_char_table));
2385 i = find_char_info_specifier_index (diag_fci, 'H');
2386 diag_fci[i].types[0].type = &loc;
2387 diag_fci[i].pointer_count = 1;
2391 i = find_char_info_specifier_index (diag_fci, 'J');
2392 diag_fci[i].types[0].type = &t;
2393 diag_fci[i].pointer_count = 1;
2396 /* Handle the __gcc_cdiag__ format specifics. */
2398 dynamic_format_types[gcc_cdiag_format_type].conversion_specs =
2399 cdiag_fci = (format_char_info *)
2400 xmemdup (gcc_cdiag_char_table,
2401 sizeof (gcc_cdiag_char_table),
2402 sizeof (gcc_cdiag_char_table));
2405 i = find_char_info_specifier_index (cdiag_fci, 'H');
2406 cdiag_fci[i].types[0].type = &loc;
2407 cdiag_fci[i].pointer_count = 1;
2411 /* All specifiers taking a tree share the same struct. */
2412 i = find_char_info_specifier_index (cdiag_fci, 'D');
2413 cdiag_fci[i].types[0].type = &t;
2414 cdiag_fci[i].pointer_count = 1;
2415 i = find_char_info_specifier_index (cdiag_fci, 'J');
2416 cdiag_fci[i].types[0].type = &t;
2417 cdiag_fci[i].pointer_count = 1;
2420 /* Handle the __gcc_cxxdiag__ format specifics. */
2422 dynamic_format_types[gcc_cxxdiag_format_type].conversion_specs =
2423 cxxdiag_fci = (format_char_info *)
2424 xmemdup (gcc_cxxdiag_char_table,
2425 sizeof (gcc_cxxdiag_char_table),
2426 sizeof (gcc_cxxdiag_char_table));
2429 i = find_char_info_specifier_index (cxxdiag_fci, 'H');
2430 cxxdiag_fci[i].types[0].type = &loc;
2431 cxxdiag_fci[i].pointer_count = 1;
2435 /* All specifiers taking a tree share the same struct. */
2436 i = find_char_info_specifier_index (cxxdiag_fci, 'D');
2437 cxxdiag_fci[i].types[0].type = &t;
2438 cxxdiag_fci[i].pointer_count = 1;
2439 i = find_char_info_specifier_index (cxxdiag_fci, 'J');
2440 cxxdiag_fci[i].types[0].type = &t;
2441 cxxdiag_fci[i].pointer_count = 1;
2446 #ifdef TARGET_FORMAT_TYPES
2447 extern const format_kind_info TARGET_FORMAT_TYPES[];
2450 /* Handle a "format" attribute; arguments as in
2451 struct attribute_spec.handler. */
2453 handle_format_attribute (tree *node, tree ARG_UNUSED (name), tree args,
2454 int flags, bool *no_add_attrs)
2457 function_format_info info;
2460 #ifdef TARGET_FORMAT_TYPES
2461 /* If the target provides additional format types, we need to
2462 add them to FORMAT_TYPES at first use. */
2463 if (TARGET_FORMAT_TYPES != NULL && !dynamic_format_types)
2465 dynamic_format_types = xmalloc ((n_format_types + TARGET_N_FORMAT_TYPES)
2466 * sizeof (dynamic_format_types[0]));
2467 memcpy (dynamic_format_types, format_types_orig,
2468 sizeof (format_types_orig));
2469 memcpy (&dynamic_format_types[n_format_types], TARGET_FORMAT_TYPES,
2470 TARGET_N_FORMAT_TYPES * sizeof (dynamic_format_types[0]));
2472 format_types = dynamic_format_types;
2473 n_format_types += TARGET_N_FORMAT_TYPES;
2477 if (!decode_format_attr (args, &info, 0))
2479 *no_add_attrs = true;
2483 argument = TYPE_ARG_TYPES (type);
2486 if (!check_format_string (argument, info.format_num, flags,
2490 if (info.first_arg_num != 0)
2492 unsigned HOST_WIDE_INT arg_num = 1;
2494 /* Verify that first_arg_num points to the last arg,
2497 arg_num++, argument = TREE_CHAIN (argument);
2499 if (arg_num != info.first_arg_num)
2501 if (!(flags & (int) ATTR_FLAG_BUILT_IN))
2502 error ("args to be formatted is not %<...%>");
2503 *no_add_attrs = true;
2509 if (info.format_type == strftime_format_type && info.first_arg_num != 0)
2511 error ("strftime formats cannot format arguments");
2512 *no_add_attrs = true;
2516 /* If this is a custom GCC-internal format type, we have to
2517 initialize certain bits a runtime. */
2518 if (info.format_type == asm_fprintf_format_type
2519 || info.format_type == gcc_diag_format_type
2520 || info.format_type == gcc_cdiag_format_type
2521 || info.format_type == gcc_cxxdiag_format_type)
2523 /* Our first time through, we have to make sure that our
2524 format_type data is allocated dynamically and is modifiable. */
2525 if (!dynamic_format_types)
2526 format_types = dynamic_format_types = (format_kind_info *)
2527 xmemdup (format_types_orig, sizeof (format_types_orig),
2528 sizeof (format_types_orig));
2530 /* If this is format __asm_fprintf__, we have to initialize
2531 GCC's notion of HOST_WIDE_INT for checking %wd. */
2532 if (info.format_type == asm_fprintf_format_type)
2533 init_dynamic_asm_fprintf_info ();
2534 /* If this is one of the diagnostic attributes, then we have to
2535 initialize 'location_t' and 'tree' at runtime. */
2536 else if (info.format_type == gcc_diag_format_type
2537 || info.format_type == gcc_cdiag_format_type
2538 || info.format_type == gcc_cxxdiag_format_type)
2539 init_dynamic_diag_info ();