gcc/flags.h

   1 /* Compilation switch flag definitions for GCC.
   2    Copyright (C) 1987, 1988, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2002,
   3    2003, 2004, 2005, 2006, 2007
   4    Free Software Foundation, Inc.
   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 #ifndef GCC_FLAGS_H
  23 #define GCC_FLAGS_H
  24
  25 #include "options.h"
  26
  27 enum debug_info_type
  28 {
  29   NO_DEBUG,         /* Write no debug info.  */
  30   DBX_DEBUG,        /* Write BSD .stabs for DBX (using dbxout.c).  */
  31   SDB_DEBUG,        /* Write COFF for (old) SDB (using sdbout.c).  */
  32   DWARF2_DEBUG,     /* Write Dwarf v2 debug info (using dwarf2out.c).  */
  33   XCOFF_DEBUG,      /* Write IBM/Xcoff debug info (using dbxout.c).  */
  34   VMS_DEBUG,        /* Write VMS debug info (using vmsdbgout.c).  */
  35   VMS_AND_DWARF2_DEBUG /* Write VMS debug info (using vmsdbgout.c).
  36                           and DWARF v2 debug info (using dwarf2out.c).  */
  37 };
  38
  39 /* Specify which kind of debugging info to generate.  */
  40 extern enum debug_info_type write_symbols;
  41
  42 /* Names of debug_info_type, for error messages.  */
  43 extern const char *const debug_type_names[];
  44
  45 enum debug_info_level
  46 {
  47   DINFO_LEVEL_NONE,     /* Write no debugging info.  */
  48   DINFO_LEVEL_TERSE,    /* Write minimal info to support tracebacks only.  */
  49   DINFO_LEVEL_NORMAL,   /* Write info for all declarations (and line table).  */
  50   DINFO_LEVEL_VERBOSE   /* Write normal info plus #define/#undef info.  */
  51 };
  52
  53 /* Specify how much debugging info to generate.  */
  54 extern enum debug_info_level debug_info_level;
  55
  56 /* Nonzero means use GNU-only extensions in the generated symbolic
  57    debugging information.  */
  58 extern bool use_gnu_debug_info_extensions;
  59
  60 /* Enumerate visibility settings.  This is deliberately ordered from most
  61    to least visibility.  */
  62 #ifndef SYMBOL_VISIBILITY_DEFINED
  63 #define SYMBOL_VISIBILITY_DEFINED
  64 enum symbol_visibility
  65 {
  66   VISIBILITY_DEFAULT,
  67   VISIBILITY_PROTECTED,
  68   VISIBILITY_HIDDEN,
  69   VISIBILITY_INTERNAL
  70 };
  71 #endif
  72
  73 /* The default visibility for all symbols (unless overridden).  */
  74 extern enum symbol_visibility default_visibility;
  75
  76 struct visibility_flags
  77 {
  78   unsigned inpragma : 1;        /* True when in #pragma GCC visibility.  */
  79   unsigned inlines_hidden : 1;  /* True when -finlineshidden in effect.  */
  80 };
  81
  82 /* Global visibility options.  */
  83 extern struct visibility_flags visibility_options;
  84
  85 /* Nonzero means do optimizations.  -opt.  */
  86
  87 extern int optimize;
  88
  89 /* Nonzero means optimize for size.  -Os.  */
  90
  91 extern int optimize_size;
  92
  93 /* Do print extra warnings (such as for uninitialized variables).
  94    -W/-Wextra.  */
  95
  96 extern bool extra_warnings;
  97
  98 /* Nonzero to warn about unused variables, functions et.al.  Use
  99    set_Wunused() to update the -Wunused-* flags that correspond to the
 100    -Wunused option.  */
 101
 102 extern void set_Wunused (int setting);
 103
 104 /* Nonzero means warn about any objects definitions whose size is larger
 105    than N bytes.  Also want about function definitions whose returned
 106    values are larger than N bytes. The value N is in `larger_than_size'.  */
 107
 108 extern bool warn_larger_than;
 109 extern HOST_WIDE_INT larger_than_size;
 110
 111 /* Nonzero means warn about constructs which might not be strict
 112    aliasing safe.  */
 113
 114 extern int warn_strict_aliasing;
 115
 116 /* Nonzero means warn about optimizations which rely on undefined
 117    signed overflow.  */
 118
 119 extern int warn_strict_overflow;
 120
 121 /* Temporarily suppress certain warnings.
 122    This is set while reading code from a system header file.  */
 123
 124 extern int in_system_header;
 125
 126 /* Nonzero for -dp: annotate the assembly with a comment describing the
 127    pattern and alternative used.  */
 128
 129 extern int flag_print_asm_name;
 130 \f
 131 /* Now the symbols that are set with `-f' switches.  */
 132
 133 /* Nonzero means `char' should be signed.  */
 134
 135 extern int flag_signed_char;
 136
 137 /* Nonzero means give an enum type only as many bytes as it needs.  A value
 138    of 2 means it has not yet been initialized.  */
 139
 140 extern int flag_short_enums;
 141
 142 /* Nonzero for -fpcc-struct-return: return values the same way PCC does.  */
 143
 144 extern int flag_pcc_struct_return;
 145
 146 /* 0 means straightforward implementation of complex divide acceptable.
 147    1 means wide ranges of inputs must work for complex divide.
 148    2 means C99-like requirements for complex multiply and divide.  */
 149
 150 extern int flag_complex_method;
 151
 152 /* Nonzero means that we don't want inlining by virtue of -fno-inline,
 153    not just because the tree inliner turned us off.  */
 154
 155 extern int flag_really_no_inline;
 156
 157 /* Nonzero if we are only using compiler to check syntax errors.  */
 158
 159 extern int rtl_dump_and_exit;
 160
 161 /* Nonzero means we should save auxiliary info into a .X file.  */
 162
 163 extern int flag_gen_aux_info;
 164
 165 /* Nonzero means suppress output of instruction numbers and line number
 166    notes in debugging dumps.  */
 167
 168 extern int flag_dump_unnumbered;
 169
 170 /* Nonzero means change certain warnings into errors.
 171    Usually these are warnings about failure to conform to some standard.  */
 172
 173 extern int flag_pedantic_errors;
 174
 175 /* Nonzero if we are compiling code for a shared library, zero for
 176    executable.  */
 177
 178 extern int flag_shlib;
 179
 180 /* -dA causes debug information to be produced in
 181    the generated assembly code (to make it more readable).  This option
 182    is generally only of use to those who actually need to read the
 183    generated assembly code (perhaps while debugging the compiler itself).
 184    Currently, this switch is only used by dwarfout.c; however, it is intended
 185    to be a catchall for printing debug information in the assembler file.  */
 186
 187 extern int flag_debug_asm;
 188
 189 /* Generate code for GNU or NeXT Objective-C runtime environment.  */
 190
 191 extern int flag_next_runtime;
 192
 193 extern int flag_dump_rtl_in_asm;
 194
 195 /* If one, renumber instruction UIDs to reduce the number of
 196    unused UIDs if there are a lot of instructions.  If greater than
 197    one, unconditionally renumber instruction UIDs.  */
 198 extern int flag_renumber_insns;
 199 \f
 200 /* Other basic status info about current function.  */
 201
 202 /* Nonzero means current function must be given a frame pointer.
 203    Set in stmt.c if anything is allocated on the stack there.
 204    Set in reload1.c if anything is allocated on the stack there.  */
 205
 206 extern int frame_pointer_needed;
 207
 208 /* Nonzero if subexpressions must be evaluated from left-to-right.  */
 209 extern int flag_evaluation_order;
 210
 211 /* Value of the -G xx switch, and whether it was passed or not.  */
 212 extern unsigned HOST_WIDE_INT g_switch_value;
 213 extern bool g_switch_set;
 214
 215 /* Values of the -falign-* flags: how much to align labels in code.
 216    0 means `use default', 1 means `don't align'.
 217    For each variable, there is an _log variant which is the power
 218    of two not less than the variable, for .align output.  */
 219
 220 extern int align_loops_log;
 221 extern int align_loops_max_skip;
 222 extern int align_jumps_log;
 223 extern int align_jumps_max_skip;
 224 extern int align_labels_log;
 225 extern int align_labels_max_skip;
 226 extern int align_functions_log;
 227
 228 /* Like align_functions_log above, but used by front-ends to force the
 229    minimum function alignment.  Zero means no alignment is forced.  */
 230 extern int force_align_functions_log;
 231
 232 /* Nonzero if we dump in VCG format, not plain text.  */
 233 extern int dump_for_graph;
 234
 235 /* Selection of the graph form.  */
 236 enum graph_dump_types
 237 {
 238   no_graph = 0,
 239   vcg
 240 };
 241 extern enum graph_dump_types graph_dump_format;
 242
 243 /* Nonzero means to collect statistics which might be expensive
 244    and to print them when we are done.  */
 245 extern int flag_detailed_statistics;
 246
 247 /* Nonzero means that we defer emitting functions until they are actually
 248    used.  */
 249 extern int flag_remove_unreachable_functions;
 250
 251 /* Nonzero if we should track variables.  */
 252 extern int flag_var_tracking;
 253
 254 /* True if flag_speculative_prefetching was set by user.  Used to suppress
 255    warning message in case flag was set by -fprofile-{generate,use}.  */
 256 extern bool flag_speculative_prefetching_set;
 257
 258 /* A string that's used when a random name is required.  NULL means
 259    to make it really random.  */
 260
 261 extern const char *flag_random_seed;
 262
 263 /* Returns TRUE if generated code should match ABI version N or
 264    greater is in use.  */
 265
 266 #define abi_version_at_least(N) \
 267   (flag_abi_version == 0 || flag_abi_version >= (N))
 268
 269 /* True if the given mode has a NaN representation and the treatment of
 270    NaN operands is important.  Certain optimizations, such as folding
 271    x * 0 into 0, are not correct for NaN operands, and are normally
 272    disabled for modes with NaNs.  The user can ask for them to be
 273    done anyway using the -funsafe-math-optimizations switch.  */
 274 #define HONOR_NANS(MODE) \
 275   (MODE_HAS_NANS (MODE) && !flag_finite_math_only)
 276
 277 /* Like HONOR_NANs, but true if we honor signaling NaNs (or sNaNs).  */
 278 #define HONOR_SNANS(MODE) (flag_signaling_nans && HONOR_NANS (MODE))
 279
 280 /* As for HONOR_NANS, but true if the mode can represent infinity and
 281    the treatment of infinite values is important.  */
 282 #define HONOR_INFINITIES(MODE) \
 283   (MODE_HAS_INFINITIES (MODE) && !flag_finite_math_only)
 284
 285 /* Like HONOR_NANS, but true if the given mode distinguishes between
 286    positive and negative zero, and the sign of zero is important.  */
 287 #define HONOR_SIGNED_ZEROS(MODE) \
 288   (MODE_HAS_SIGNED_ZEROS (MODE) && !flag_unsafe_math_optimizations)
 289
 290 /* Like HONOR_NANS, but true if given mode supports sign-dependent rounding,
 291    and the rounding mode is important.  */
 292 #define HONOR_SIGN_DEPENDENT_ROUNDING(MODE) \
 293   (MODE_HAS_SIGN_DEPENDENT_ROUNDING (MODE) && flag_rounding_math)
 294
 295 /* True if overflow wraps around for the given integral type.  That
 296    is, TYPE_MAX + 1 == TYPE_MIN.  */
 297 #define TYPE_OVERFLOW_WRAPS(TYPE) \
 298   (TYPE_UNSIGNED (TYPE) || flag_wrapv)
 299
 300 /* True if overflow is undefined for the given integral type.  We may
 301    optimize on the assumption that values in the type never overflow.
 302
 303    IMPORTANT NOTE: Any optimization based on TYPE_OVERFLOW_UNDEFINED
 304    must issue a warning based on warn_strict_overflow.  In some cases
 305    it will be appropriate to issue the warning immediately, and in
 306    other cases it will be appropriate to simply set a flag and let the
 307    caller decide whether a warning is appropriate or not.  */
 308 #define TYPE_OVERFLOW_UNDEFINED(TYPE) \
 309   (!TYPE_UNSIGNED (TYPE) && !flag_wrapv && !flag_trapv && flag_strict_overflow)
 310
 311 /* True if overflow for the given integral type should issue a
 312    trap.  */
 313 #define TYPE_OVERFLOW_TRAPS(TYPE) \
 314   (!TYPE_UNSIGNED (TYPE) && flag_trapv)
 315
 316 /* Names for the different levels of -Wstrict-overflow=N.  The numeric
 317    values here correspond to N.  */
 318
 319 enum warn_strict_overflow_code
 320 {
 321   /* Overflow warning that should be issued with -Wall: a questionable
 322      construct that is easy to avoid even when using macros.  Example:
 323      folding (x + CONSTANT > x) to 1.  */
 324   WARN_STRICT_OVERFLOW_ALL = 1,
 325   /* Overflow warning about folding a comparison to a constant because
 326      of undefined signed overflow, other than cases covered by
 327      WARN_STRICT_OVERFLOW_ALL.  Example: folding (abs (x) >= 0) to 1
 328      (this is false when x == INT_MIN).  */
 329   WARN_STRICT_OVERFLOW_CONDITIONAL = 2,
 330   /* Overflow warning about changes to comparisons other than folding
 331      them to a constant.  Example: folding (x + 1 > 1) to (x > 0).  */
 332   WARN_STRICT_OVERFLOW_COMPARISON = 3,
 333   /* Overflow warnings not covered by the above cases.  Example:
 334      folding ((x * 10) / 5) to (x * 2).  */
 335   WARN_STRICT_OVERFLOW_MISC = 4,
 336   /* Overflow warnings about reducing magnitude of constants in
 337      comparison.  Example: folding (x + 2 > y) to (x + 1 >= y).  */
 338   WARN_STRICT_OVERFLOW_MAGNITUDE = 5
 339 };
 340
 341 /* Whether to emit an overflow warning whose code is C.  */
 342 #define issue_strict_overflow_warning(c) (warn_strict_overflow >= (int) (c))
 343
 344 #endif /* ! GCC_FLAGS_H */