/* Command line option handling. Copyright (C) 2002, 2003 Free Software Foundation, Inc. Contributed by Neil Booth. This file is part of GCC. GCC is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2, or (at your option) any later version. GCC is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with GCC; see the file COPYING. If not, write to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ #include "config.h" #include "system.h" #include "coretypes.h" #include "tm.h" #include "tree.h" #include "rtl.h" #include "ggc.h" #include "output.h" #include "langhooks.h" #include "opts.h" #include "options.h" #include "flags.h" #include "toplev.h" #include "params.h" #include "diagnostic.h" /* Value of the -G xx switch, and whether it was passed or not. */ unsigned HOST_WIDE_INT g_switch_value; bool g_switch_set; /* True if we should exit after parsing options. */ bool exit_after_options; /* If -version. */ bool version_flag; /* Print various extra warnings. -W/-Wextra. */ bool extra_warnings; /* Don't print warning messages. -w. */ bool inhibit_warnings; /* Treat warnings as errors. -Werror. */ bool warnings_are_errors; /* Warn if a function returns an aggregate, since there are often incompatible calling conventions for doing this. */ bool warn_aggregate_return; /* Nonzero means warn about pointer casts that increase the required alignment of the target type (and might therefore lead to a crash due to a misaligned access). */ bool warn_cast_align; /* Nonzero means warn about uses of __attribute__((deprecated)) declarations. */ bool warn_deprecated_decl = true; /* Warn when an optimization pass is disabled. */ bool warn_disabled_optimization; /* Nonzero means warn if inline function is too large. */ bool warn_inline; /* True to warn about any objects definitions whose size is larger than N bytes. Also want about function definitions whose returned values are larger than N bytes, where N is `larger_than_size'. */ bool warn_larger_than; HOST_WIDE_INT larger_than_size; /* Warn about functions which might be candidates for attribute noreturn. */ bool warn_missing_noreturn; /* True to warn about code which is never reached. */ bool warn_notreached; /* Warn if packed attribute on struct is unnecessary and inefficient. */ bool warn_packed; /* Warn when gcc pads a structure to an alignment boundary. */ bool warn_padded; /* True means warn about all declarations which shadow others. */ bool warn_shadow; /* Nonzero means warn about constructs which might not be strict-aliasing safe. */ bool warn_strict_aliasing; /* True to warn if a switch on an enum, that does not have a default case, fails to have a case for every enum value. */ bool warn_switch; /* Warn if a switch does not have a default case. */ bool warn_switch_default; /* Warn if a switch on an enum fails to have a case for every enum value (regardless of the presence or otherwise of a default case). */ bool warn_switch_enum; /* Don't suppress warnings from system headers. -Wsystem-headers. */ bool warn_system_headers; /* True to warn about variables used before they are initialized. */ int warn_uninitialized; /* True to warn about unused variables, functions et.al. */ bool warn_unused_function; bool warn_unused_label; bool warn_unused_parameter; bool warn_unused_variable; bool warn_unused_value; /* Hack for cooperation between set_Wunused and set_Wextra. */ static bool maybe_warn_unused_parameter; static size_t find_opt (const char *, int); static int common_handle_option (size_t scode, const char *arg, int value); static void handle_param (const char *); static void set_Wextra (int); /* Perform a binary search to find which option the command-line INPUT matches. Returns its index in the option array, and N_OPTS (cl_options_count) on failure. This routine is quite subtle. A normal binary search is not good enough because some options can be suffixed with an argument, and multiple sub-matches can occur, e.g. input of "-pedantic" matching the initial substring of "-pedantic-errors". A more complicated example is -gstabs. It should match "-g" with an argument of "stabs". Suppose, however, that the number and list of switches are such that the binary search tests "-gen-decls" before having tested "-g". This doesn't match, and as "-gen-decls" is less than "-gstabs", it will become the lower bound of the binary search range, and "-g" will never be seen. To resolve this issue, opts.sh makes "-gen-decls" point, via the back_chain member, to "-g" so that failed searches that end between "-gen-decls" and the lexicographically subsequent switch know to go back and see if "-g" causes a match (which it does in this example). This search is done in such a way that the longest match for the front end in question wins. If there is no match for the current front end, the longest match for a different front end is returned (or N_OPTS if none) and the caller emits an error message. */ static size_t find_opt (const char *input, int lang_mask) { size_t mn, mx, md, opt_len; size_t match_wrong_lang; int comp; mn = 0; mx = cl_options_count; /* Find mn such this lexicographical inequality holds: cl_options[mn] <= input < cl_options[mn + 1]. */ while (mx - mn > 1) { md = (mn + mx) / 2; opt_len = cl_options[md].opt_len; comp = strncmp (input, cl_options[md].opt_text, opt_len); if (comp < 0) mx = md; else mn = md; } /* This is the switch that is the best match but for a different front end, or cl_options_count if there is no match at all. */ match_wrong_lang = cl_options_count; /* Backtrace the chain of possible matches, returning the longest one, if any, that fits best. With current GCC switches, this loop executes at most twice. */ do { const struct cl_option *opt = &cl_options[mn]; /* Is this switch a prefix of the input? */ if (!strncmp (input, opt->opt_text, opt->opt_len)) { /* If language is OK, and the match is exact or the switch takes a joined argument, return it. */ if ((opt->flags & lang_mask) && (input[opt->opt_len] == '\0' || (opt->flags & CL_JOINED))) return mn; /* If we haven't remembered a prior match, remember this one. Any prior match is necessarily better. */ if (match_wrong_lang != cl_options_count) match_wrong_lang = mn; } /* Try the next possibility. This is cl_options_count if there are no more. */ mn = opt->back_chain; } while (mn != cl_options_count); /* Return the best wrong match, or cl_options_count if none. */ return match_wrong_lang; } /* If ARG is a non-negative integer made up solely of digits, return its value, otherwise return -1. */ static int integral_argument (const char *arg) { const char *p = arg; while (*p && ISDIGIT (*p)) p++; if (*p == '\0') return atoi (arg); return -1; } /* Handle the switch beginning at ARGV, with ARGC remaining. */ int handle_option (int argc ATTRIBUTE_UNUSED, char **argv, int lang_mask) { size_t opt_index; const char *opt, *arg = 0; char *dup = 0; int value = 1; int result = 0; const struct cl_option *option; opt = argv[0]; /* Interpret "-" or a non-switch as a file name. */ if (opt[0] != '-' || opt[1] == '\0') { opt_index = cl_options_count; arg = opt; main_input_filename = opt; result = (*lang_hooks.handle_option) (opt_index, arg, value); } else { /* Drop the "no-" from negative switches. */ if ((opt[1] == 'W' || opt[1] == 'f') && opt[2] == 'n' && opt[3] == 'o' && opt[4] == '-') { size_t len = strlen (opt) - 3; dup = xmalloc (len + 1); dup[0] = '-'; dup[1] = opt[1]; memcpy (dup + 2, opt + 5, len - 2 + 1); opt = dup; value = 0; } opt_index = find_opt (opt + 1, lang_mask | CL_COMMON); if (opt_index == cl_options_count) goto done; option = &cl_options[opt_index]; /* Reject negative form of switches that don't take negatives. */ if (!value && (option->flags & CL_REJECT_NEGATIVE)) goto done; /* We've recognized this switch. */ result = 1; /* Sort out any argument the switch takes. */ if (option->flags & CL_JOINED) { /* Have arg point to the original switch. This is because some code, such as disable_builtin_function, expects its argument to be persistent until the program exits. */ arg = argv[0] + cl_options[opt_index].opt_len + 1; if (!value) arg += strlen ("no-"); if (*arg == '\0' && !(option->flags & CL_MISSING_OK)) { if (option->flags & CL_SEPARATE) { arg = argv[1]; result = 2; } else /* Missing argument. */ arg = NULL; } } else if (option->flags & CL_SEPARATE) { arg = argv[1]; result = 2; } /* If the switch takes an integer, convert it. */ if (arg && (option->flags & CL_UINTEGER)) { value = integral_argument (arg); if (value == -1) { error ("argument to \"-%s\" should be a non-negative integer", option->opt_text); goto done; } } if (option->flags & lang_mask) if ((*lang_hooks.handle_option) (opt_index, arg, value) == 0) result = 0; if (result && (option->flags & CL_COMMON)) if (common_handle_option (opt_index, arg, value) == 0) result = 0; } done: if (dup) free (dup); return result; } /* Handle target- and language-independent options. Return zero to generate an "unknown option" message. */ static int common_handle_option (size_t scode, const char *arg, int value ATTRIBUTE_UNUSED) { const struct cl_option *option = &cl_options[scode]; enum opt_code code = (enum opt_code) scode; if (arg == NULL && (option->flags & (CL_JOINED | CL_SEPARATE))) { error ("missing argument to \"-%s\"", option->opt_text); return 1; } switch (code) { default: abort (); case OPT__help: display_help (); exit_after_options = true; break; case OPT__param: handle_param (arg); break; case OPT__target_help: display_target_options (); exit_after_options = true; break; case OPT__version: print_version (stderr, ""); exit_after_options = true; break; case OPT_G: g_switch_value = value; g_switch_set = true; break; case OPT_O: case OPT_Os: /* Currently handled in a prescan. */ break; case OPT_W: /* For backward compatibility, -W is the same as -Wextra. */ set_Wextra (value); break; case OPT_Waggregate_return: warn_aggregate_return = value; break; case OPT_Wcast_align: warn_cast_align = value; break; case OPT_Wdeprecated_declarations: warn_deprecated_decl = value; case OPT_Wdisabled_optimization: warn_disabled_optimization = value; break; case OPT_Werror: warnings_are_errors = value; break; case OPT_Wextra: set_Wextra (value); break; case OPT_Winline: warn_inline = value; break; case OPT_Wlarger_than_: larger_than_size = value; warn_larger_than = value != -1; break; case OPT_Wmissing_noreturn: warn_missing_noreturn = value; break; case OPT_Wpacked: warn_packed = value; break; case OPT_Wpadded: warn_padded = value; break; case OPT_Wshadow: warn_shadow = value; break; case OPT_Wstrict_aliasing: warn_strict_aliasing = value; break; case OPT_Wswitch: warn_switch = value; break; case OPT_Wswitch_default: warn_switch_default = value; break; case OPT_Wswitch_enum: warn_switch_enum = value; break; case OPT_Wsystem_headers: warn_system_headers = value; break; case OPT_Wuninitialized: warn_uninitialized = value; break; case OPT_Wunreachable_code: warn_notreached = value; break; case OPT_Wunused: set_Wunused (value); break; case OPT_Wunused_function: warn_unused_function = value; break; case OPT_Wunused_label: warn_unused_label = value; break; case OPT_Wunused_parameter: warn_unused_parameter = value; break; case OPT_Wunused_value: warn_unused_value = value; break; case OPT_Wunused_variable: warn_unused_variable = value; break; case OPT_aux_info: case OPT_aux_info_: aux_info_file_name = arg; flag_gen_aux_info = 1; break; case OPT_auxbase: aux_base_name = arg; break; case OPT_auxbase_strip: { char *tmp = xstrdup (arg); strip_off_ending (tmp, strlen (tmp)); if (tmp[0]) aux_base_name = tmp; } break; case OPT_d: decode_d_option (arg); break; case OPT_dumpbase: dump_base_name = arg; break; case OPT_fPIC: flag_pic = value + value; break; case OPT_fPIE: flag_pie = value + value; break; case OPT_falign_functions: case OPT_falign_functions_: align_functions = value; break; case OPT_falign_jumps: case OPT_falign_jumps_: align_jumps = value; break; case OPT_falign_labels: case OPT_falign_labels_: align_labels = value; break; case OPT_falign_loops: case OPT_falign_loops_: align_loops = value; break; case OPT_fargument_alias: flag_argument_noalias = !value; break; case OPT_fargument_noalias: flag_argument_noalias = value; break; case OPT_fargument_noalias_global: flag_argument_noalias = value + value; break; case OPT_fasynchronous_unwind_tables: flag_asynchronous_unwind_tables = value; break; case OPT_fbounds_check: flag_bounds_check = value; break; case OPT_fbranch_count_reg: flag_branch_on_count_reg = value; break; case OPT_fbranch_probabilities: flag_branch_probabilities = value; break; case OPT_fbranch_target_load_optimize: flag_branch_target_load_optimize = value; break; case OPT_fbranch_target_load_optimize2: flag_branch_target_load_optimize2 = value; break; case OPT_fcall_used_: fix_register (arg, 0, 1); break; case OPT_fcall_saved_: fix_register (arg, 0, 0); break; case OPT_fcaller_saves: flag_caller_saves = value; break; case OPT_fcommon: flag_no_common = !value; break; case OPT_fcprop_registers: flag_cprop_registers = value; break; case OPT_fcrossjumping: flag_crossjumping = value; break; case OPT_fcse_follow_jumps: flag_cse_follow_jumps = value; break; case OPT_fcse_skip_blocks: flag_cse_skip_blocks = value; break; case OPT_fdata_sections: flag_data_sections = value; break; case OPT_fdefer_pop: flag_defer_pop = value; break; case OPT_fdelayed_branch: flag_delayed_branch = value; break; case OPT_fdelete_null_pointer_checks: flag_delete_null_pointer_checks = value; break; case OPT_fdiagnostics_show_location_: if (!strcmp (arg, "once")) diagnostic_prefixing_rule (global_dc) = DIAGNOSTICS_SHOW_PREFIX_ONCE; else if (!strcmp (arg, "every-line")) diagnostic_prefixing_rule (global_dc) = DIAGNOSTICS_SHOW_PREFIX_EVERY_LINE; else return 0; break; case OPT_fdump_unnumbered: flag_dump_unnumbered = value; break; case OPT_feliminate_dwarf2_dups: flag_eliminate_dwarf2_dups = value; break; case OPT_feliminate_unused_debug_types: flag_eliminate_unused_debug_types = value; break; case OPT_fexceptions: flag_exceptions = value; break; case OPT_fexpensive_optimizations: flag_expensive_optimizations = value; break; case OPT_ffast_math: set_fast_math_flags (value); break; case OPT_ffinite_math_only: flag_finite_math_only = value; break; case OPT_ffixed_: fix_register (arg, 1, 1); break; case OPT_ffunction_cse: flag_no_function_cse = !value; break; case OPT_ffloat_store: flag_float_store = value; break; case OPT_fforce_addr: flag_force_addr = value; break; case OPT_fforce_mem: flag_force_mem = value; break; case OPT_ffunction_sections: flag_function_sections = value; break; case OPT_fgcse: flag_gcse = value; break; case OPT_fgcse_lm: flag_gcse_lm = value; break; case OPT_fgcse_sm: flag_gcse_sm = value; break; case OPT_fgnu_linker: flag_gnu_linker = value; break; case OPT_fguess_branch_probability: flag_guess_branch_prob = value; break; case OPT_fident: flag_no_ident = !value; break; case OPT_fif_conversion: flag_if_conversion = value; break; case OPT_fif_conversion2: flag_if_conversion2 = value; break; case OPT_finhibit_size_directive: flag_inhibit_size_directive = value; break; case OPT_finline: flag_no_inline = !value; break; case OPT_finline_functions: flag_inline_functions = value; break; case OPT_finline_limit_: case OPT_finline_limit_eq: set_param_value ("max-inline-insns", value); set_param_value ("max-inline-insns-single", value / 2); set_param_value ("max-inline-insns-auto", value / 2); set_param_value ("max-inline-insns-rtl", value); if (value / 4 < MIN_INLINE_INSNS) { if (value / 4 > 10) set_param_value ("min-inline-insns", value / 4); else set_param_value ("min-inline-insns", 10); } break; case OPT_finstrument_functions: flag_instrument_function_entry_exit = value; break; case OPT_fkeep_inline_functions: flag_keep_inline_functions =value; break; case OPT_fkeep_static_consts: flag_keep_static_consts = value; break; case OPT_fleading_underscore: flag_leading_underscore = value; break; case OPT_floop_optimize: flag_loop_optimize = value; break; case OPT_fmath_errno: flag_errno_math = value; break; case OPT_fmem_report: mem_report = value; break; case OPT_fmerge_all_constants: flag_merge_constants = value + value; break; case OPT_fmerge_constants: flag_merge_constants = value; break; case OPT_fmessage_length_: output_set_maximum_length (&global_dc->buffer, value); break; case OPT_fmove_all_movables: flag_move_all_movables = value; break; case OPT_fnew_ra: flag_new_regalloc = value; break; case OPT_fnon_call_exceptions: flag_non_call_exceptions = value; break; case OPT_fold_unroll_all_loops: flag_old_unroll_all_loops = value; break; case OPT_fold_unroll_loops: flag_old_unroll_loops = value; break; case OPT_fomit_frame_pointer: flag_omit_frame_pointer = value; break; case OPT_foptimize_register_move: flag_regmove = value; break; case OPT_foptimize_sibling_calls: flag_optimize_sibling_calls = value; break; case OPT_fpack_struct: flag_pack_struct = value; break; case OPT_fpeel_loops: flag_peel_loops = value; break; case OPT_fpcc_struct_return: flag_pcc_struct_return = value; break; case OPT_fpeephole: flag_no_peephole = !value; break; case OPT_fpeephole2: flag_peephole2 = value; break; case OPT_fpic: flag_pic = value; break; case OPT_fpie: flag_pie = value; break; case OPT_fprefetch_loop_arrays: flag_prefetch_loop_arrays = value; break; case OPT_fprofile: profile_flag = value; break; case OPT_fprofile_arcs: profile_arc_flag = value; break; case OPT_frandom_seed: /* The real switch is -fno-random-seed. */ if (value) return 0; flag_random_seed = NULL; break; case OPT_frandom_seed_: flag_random_seed = arg; break; case OPT_freduce_all_givs: flag_reduce_all_givs = value; break; case OPT_freg_struct_return: flag_pcc_struct_return = !value; break; case OPT_fregmove: flag_regmove = value; break; case OPT_frename_registers: flag_rename_registers = value; break; case OPT_freorder_blocks: flag_reorder_blocks = value; break; case OPT_freorder_functions: flag_reorder_functions = value; break; case OPT_frerun_cse_after_loop: flag_rerun_cse_after_loop = value; break; case OPT_frerun_loop_opt: flag_rerun_loop_opt = value; break; case OPT_fsched_interblock: flag_schedule_interblock= value; break; case OPT_fsched_spec: flag_schedule_speculative = value; break; case OPT_fsched_spec_load: flag_schedule_speculative_load = value; break; case OPT_fsched_spec_load_dangerous: flag_schedule_speculative_load_dangerous = value; break; case OPT_fsched_verbose_: #ifdef INSN_SCHEDULING fix_sched_param ("verbose", arg); break; #else return 0; #endif case OPT_fsched2_use_superblocks: flag_sched2_use_superblocks = value; break; case OPT_fsched2_use_traces: flag_sched2_use_traces = value; break; case OPT_fschedule_insns: flag_schedule_insns = value; break; case OPT_fschedule_insns2: flag_schedule_insns_after_reload = value; break; case OPT_fshared_data: flag_shared_data = value; break; case OPT_fsignaling_nans: flag_signaling_nans = value; break; case OPT_fsingle_precision_constant: flag_single_precision_constant = value; break; case OPT_fssa: flag_ssa = value; break; case OPT_fssa_ccp: flag_ssa_ccp = value; break; case OPT_fssa_dce: flag_ssa_dce = value; break; case OPT_fstack_check: flag_stack_check = value; break; case OPT_fstack_limit: /* The real switch is -fno-stack-limit. */ if (value) return 0; stack_limit_rtx = NULL_RTX; break; case OPT_fstack_limit_register_: { int reg = decode_reg_name (arg); if (reg < 0) error ("unrecognized register name \"%s\"", arg); else stack_limit_rtx = gen_rtx_REG (Pmode, reg); } break; case OPT_fstack_limit_symbol_: stack_limit_rtx = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (arg)); break; case OPT_fstrength_reduce: flag_strength_reduce = value; break; case OPT_fstrict_aliasing: flag_strict_aliasing = value; break; case OPT_fsyntax_only: flag_syntax_only = value; break; case OPT_ftest_coverage: flag_test_coverage = value; break; case OPT_fthread_jumps: flag_thread_jumps = value; break; case OPT_ftime_report: time_report = value; case OPT_ftls_model_: if (!strcmp (arg, "global-dynamic")) flag_tls_default = TLS_MODEL_GLOBAL_DYNAMIC; else if (!strcmp (arg, "local-dynamic")) flag_tls_default = TLS_MODEL_LOCAL_DYNAMIC; else if (!strcmp (arg, "initial-exec")) flag_tls_default = TLS_MODEL_INITIAL_EXEC; else if (!strcmp (arg, "local-exec")) flag_tls_default = TLS_MODEL_LOCAL_EXEC; else warning ("unknown tls-model \"%s\"", arg); break; case OPT_ftracer: flag_tracer = value; break; case OPT_ftrapping_math: flag_trapping_math = value; break; case OPT_ftrapv: flag_trapv = value; break; case OPT_funit_at_a_time: flag_unit_at_a_time = value; break; case OPT_funroll_all_loops: flag_unroll_all_loops = value; break; case OPT_funroll_loops: flag_unroll_loops = value; break; case OPT_funsafe_math_optimizations: flag_unsafe_math_optimizations = value; break; case OPT_funswitch_loops: flag_unswitch_loops = value; break; case OPT_funwind_tables: flag_unwind_tables = value; break; case OPT_fverbose_asm: flag_verbose_asm = value; break; case OPT_fwrapv: flag_wrapv = value; break; case OPT_fwritable_strings: flag_writable_strings = value; break; case OPT_fzero_initialized_in_bss: flag_zero_initialized_in_bss = value; break; case OPT_g: decode_g_option (arg); break; case OPT_m: set_target_switch (arg); break; case OPT_o: asm_file_name = arg; break; case OPT_p: profile_flag = 1; break; case OPT_pedantic: pedantic = 1; break; case OPT_pedantic_errors: flag_pedantic_errors = pedantic = 1; break; case OPT_quiet: quiet_flag = 1; break; case OPT_version: version_flag = 1; break; case OPT_w: inhibit_warnings = true; break; } return 1; } /* Handle --param NAME=VALUE. */ static void handle_param (const char *carg) { char *equal, *arg; int value; arg = xstrdup (carg); equal = strchr (arg, '='); if (!equal) error ("%s: --param arguments should be of the form NAME=VALUE", arg); else { value = integral_argument (equal + 1); if (value == -1) error ("invalid --param value `%s'", equal + 1); else { *equal = '\0'; set_param_value (arg, value); } } free (arg); } /* Handle -W and -Wextra. */ static void set_Wextra (int setting) { extra_warnings = setting; warn_unused_value = setting; warn_unused_parameter = (setting && maybe_warn_unused_parameter); /* We save the value of warn_uninitialized, since if they put -Wuninitialized on the command line, we need to generate a warning about not using it without also specifying -O. */ if (setting == 0) warn_uninitialized = 0; else if (warn_uninitialized != 1) warn_uninitialized = 2; } /* Initialize unused warning flags. */ void set_Wunused (int setting) { warn_unused_function = setting; warn_unused_label = setting; /* Unused function parameter warnings are reported when either ``-Wextra -Wunused'' or ``-Wunused-parameter'' is specified. Thus, if -Wextra has already been seen, set warn_unused_parameter; otherwise set maybe_warn_extra_parameter, which will be picked up by set_Wextra. */ maybe_warn_unused_parameter = setting; warn_unused_parameter = (setting && extra_warnings); warn_unused_variable = setting; warn_unused_value = setting; } /* The following routines are useful in setting all the flags that -ffast-math and -fno-fast-math imply. */ void set_fast_math_flags (int set) { flag_trapping_math = !set; flag_unsafe_math_optimizations = set; flag_finite_math_only = set; flag_errno_math = !set; if (set) flag_signaling_nans = 0; } /* Return true iff flags are set as if -ffast-math. */ bool fast_math_flags_set_p (void) { return (!flag_trapping_math && flag_unsafe_math_optimizations && flag_finite_math_only && !flag_errno_math); }