flags.h

这是完整的gcc源代码

/* Compilation switch flag definitions for GNU CC.
   Copyright (C) 1987, 1988 Free Software Foundation, Inc.

This file is part of GNU CC.

GNU CC 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 1, or (at your option)
any later version.

GNU CC 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 GNU CC; see the file COPYING.  If not, write to
the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.  */

/* Name of the input .c file being compiled.  */
extern char *main_input_filename;

/* 1 => write gdb debugging output (using symout.c).
   2 => write dbx debugging output (using dbxout.c).
   3 => write sdb debugging output (using sdbout.c).  */
enum debugger { NO_DEBUG = 0, GDB_DEBUG = 1, DBX_DEBUG = 2, SDB_DEBUG = 3,
		EXTENDED_DBX_DEBUG = 4 };

extern enum debugger write_symbols;

/* Nonzero means use GDB-only extensions of DBX format.  */
extern int use_gdb_dbx_extensions;

/* Nonzero means do optimizations.  -opt.  */

extern int optimize;

/* Nonzero means do stupid register allocation.  -noreg.
   This and `optimize' are controlled by different switches in cc1,
   but normally cc controls them both with the -O switch.  */

extern int obey_regdecls;

/* Don't print functions as they are compiled and don't print
   times taken by the various passes.  -quiet.  */

extern int quiet_flag;

/* Don't print warning messages.  -w.  */

extern int inhibit_warnings;

/* Do print extra warnings (such as for uninitialized variables).  -W.  */

extern int extra_warnings;

/* Nonzero to warn about unused local variables.  */

extern int warn_unused;

/* Nonzero means warn about all declarations which shadow others.   */

extern int warn_shadow;

/* Warn if a switch on an enum fails to have a case for every enum value.  */

extern int warn_switch;

/* Nonzero means warn about any identifiers that match in the first N
   characters.  The value N is in `id_clash_len'.  */

extern int warn_id_clash;
extern int id_clash_len;

/* Nonzero if generating code to do profiling.  */

extern int profile_flag;

/* Nonzero if generating code to do profiling on the basis of basic blocks.  */

extern int profile_block_flag;

/* Nonzero for -pedantic switch: warn about anything
   that standard C forbids.  */

extern int pedantic;

/* Now the symbols that are set with `-f' switches.  */

/* Nonzero means `char' should be signed.  */

extern int flag_signed_char;

/* Nonzero means give an enum type only as many bytes as it needs.  */

extern int flag_short_enums;

/* Nonzero for -fcaller-saves: allocate values in regs that need to
   be saved across function calls, if that produces overall better code.
   Optional now, so people can test it.  */

extern int flag_caller_saves;

/* Nonzero for -fpcc-struct-return: return values the same way PCC does.  */

extern int flag_pcc_struct_return;

/* Nonzero for -fforce-mem: load memory value into a register
   before arithmetic on it.  This makes better cse but slower compilation.  */

extern int flag_force_mem;

/* Nonzero for -fforce-addr: load memory address into a register before
   reference to memory.  This makes better cse but slower compilation.  */

extern int flag_force_addr;

/* Nonzero for -fdefer-pop: don't pop args after each function call;
   instead save them up to pop many calls' args with one insns.  */

extern int flag_defer_pop;

/* Nonzero for -ffloat-store: don't allocate floats and doubles
   in extended-precision registers.  */

extern int flag_float_store;

/* Nonzero for -fcombine-regs:
   allow instruction combiner to combine an insn
   that just copies one reg to another.  */

extern int flag_combine_regs;

/* Nonzero enables strength-reduction in loop.c.  */

extern int flag_strength_reduce;

/* Nonzero for -fwritable-strings:
   store string constants in data segment and don't uniquize them.  */

extern int flag_writable_strings;

/* Nonzero means don't put addresses of constant functions in registers.
   Used for compiling the Unix kernel, where strange substitutions are
   done on the assembly output.  */

extern int flag_no_function_cse;

/* Nonzero for -fomit-frame-pointer:
   don't make a frame pointer in simple functions that don't require one.  */

extern int flag_omit_frame_pointer;

/* This isn't a flag, but everyone who needs flag_omit_frame_pointer
   also needs this.
   Nonzero means current function must be given a frame pointer.
   Set in stmt.c if anything is allocated on the stack there.
   Set in reload1.c if anything is allocated on the stack there.  */

extern int frame_pointer_needed;

/* Nonzero to inhibit use of define_optimization peephole opts.  */

extern int flag_no_peephole;

/* Nonzero means all references through pointers are volatile.  */

extern int flag_volatile;

/* Nonzero means make functions that look like good inline candidates
   go inline.  */

extern int flag_inline_functions;

/* Nonzero for -fkeep-inline-functions: even if we make a function
   go inline everywhere, keep its defintion around for debugging
   purposes.  */

extern int flag_keep_inline_functions;

/* Nonzero if we are only using compiler to check syntax errors.  */

extern int flag_syntax_only;

/* Nonzero means make the text shared if supported.  */

extern int flag_shared_data;

/* Nonzero means put things in delayed-branch slots if supported. */

extern int flag_delayed_branch;