Hi.
Last week I was curious which warnings are disabled by default on top
of -Wall and -Wextra. Thus I used --help=warning and noticed some discrepancy
in between documentation and output of the --help option.
I created PR89885 where I explained that OPT__help_ option handling happens
early. That's why LangEnabledBy are not reflected and similarly target overrides
don't take place.
I'm attaching diff for --help=warning for C++ and -Ofast.
Thoughts?
gcc/ChangeLog:
2019-04-01 Martin Liska <mli...@suse.cz>
* gcc.c (process_command): Add dummy file only
if n_infiles == 0.
* opts-global.c (decode_options): Pass lang_mask.
* opts.c (print_help): New function.
(finish_options): Print --help if help_option_argument
is set.
(common_handle_option): Factor out content of OPT__help_
into print_help.
* opts.h (finish_options): Add new argument.
---
gcc/gcc.c | 3 +-
gcc/opts-global.c | 2 +-
gcc/opts.c | 267 ++++++++++++++++++++++++----------------------
gcc/opts.h | 3 +-
4 files changed, 146 insertions(+), 129 deletions(-)
diff --git a/gcc/gcc.c b/gcc/gcc.c
index 4f57765b012..7ce1cae28a7 100644
--- a/gcc/gcc.c
+++ b/gcc/gcc.c
@@ -4751,7 +4751,8 @@ process_command (unsigned int decoded_options_count,
}
/* Ensure we only invoke each subprocess once. */
- if (print_subprocess_help || print_help_list || print_version)
+ if (n_infiles == 0
+ && (print_subprocess_help || print_help_list || print_version))
{
n_infiles = 0;
diff --git a/gcc/opts-global.c b/gcc/opts-global.c
index a5e9ef0237a..f110fe1026f 100644
--- a/gcc/opts-global.c
+++ b/gcc/opts-global.c
@@ -314,7 +314,7 @@ decode_options (struct gcc_options *opts, struct gcc_options *opts_set,
loc, lang_mask,
&handlers, dc);
- finish_options (opts, opts_set, loc);
+ finish_options (opts, opts_set, loc, lang_mask);
}
/* Hold command-line options associated with stack limitation. */
diff --git a/gcc/opts.c b/gcc/opts.c
index 02f6b4656e1..707e6754294 100644
--- a/gcc/opts.c
+++ b/gcc/opts.c
@@ -854,12 +854,18 @@ control_options_for_live_patching (struct gcc_options *opts,
}
}
+/* --help option argument if set. */
+const char *help_option_argument = NULL;
+
+static void print_help (struct gcc_options *opts, unsigned int lang_mask);
+
+
/* After all options at LOC have been read into OPTS and OPTS_SET,
finalize settings of those options and diagnose incompatible
combinations. */
void
finish_options (struct gcc_options *opts, struct gcc_options *opts_set,
- location_t loc)
+ location_t loc, unsigned int lang_mask)
{
enum unwind_info_type ui_except;
@@ -1223,6 +1229,10 @@ finish_options (struct gcc_options *opts, struct gcc_options *opts_set,
opts->x_flag_live_patching,
loc);
}
+
+ /* Print --help=* if used. */
+ if (help_option_argument != NULL)
+ print_help (opts, lang_mask);
}
#define LEFT_COLUMN 27
@@ -2052,6 +2062,135 @@ check_alignment_argument (location_t loc, const char *flag, const char *name)
parse_and_check_align_values (flag, name, align_result, true, loc);
}
+/* Print help when OPT__help_ is set. */
+
+static void
+print_help (struct gcc_options *opts, unsigned int lang_mask)
+{
+ const char *a = help_option_argument;
+ unsigned int include_flags = 0;
+ /* Note - by default we include undocumented options when listing
+ specific classes. If you only want to see documented options
+ then add ",^undocumented" to the --help= option. E.g.:
+
+ --help=target,^undocumented */
+ unsigned int exclude_flags = 0;
+
+ if (lang_mask == CL_DRIVER)
+ return;
+
+ /* Walk along the argument string, parsing each word in turn.
+ The format is:
+ arg = [^]{word}[,{arg}]
+ word = {optimizers|target|warnings|undocumented|
+ params|common|<language>} */
+ while (*a != 0)
+ {
+ static const struct
+ {
+ const char *string;
+ unsigned int flag;
+ }
+ specifics[] =
+ {
+ { "optimizers", CL_OPTIMIZATION },
+ { "target", CL_TARGET },
+ { "warnings", CL_WARNING },
+ { "undocumented", CL_UNDOCUMENTED },
+ { "params", CL_PARAMS },
+ { "joined", CL_JOINED },
+ { "separate", CL_SEPARATE },
+ { "common", CL_COMMON },
+ { NULL, 0 }
+ };
+ unsigned int *pflags;
+ const char *comma;
+ unsigned int lang_flag, specific_flag;
+ unsigned int len;
+ unsigned int i;
+
+ if (*a == '^')
+ {
+ ++a;
+ if (*a == '\0')
+ {
+ error ("missing argument to %qs", "--help=^");
+ break;
+ }
+ pflags = &exclude_flags;
+ }
+ else
+ pflags = &include_flags;
+
+ comma = strchr (a, ',');
+ if (comma == NULL)
+ len = strlen (a);
+ else
+ len = comma - a;
+ if (len == 0)
+ {
+ a = comma + 1;
+ continue;
+ }
+
+ /* Check to see if the string matches an option class name. */
+ for (i = 0, specific_flag = 0; specifics[i].string != NULL; i++)
+ if (strncasecmp (a, specifics[i].string, len) == 0)
+ {
+ specific_flag = specifics[i].flag;
+ break;
+ }
+
+ /* Check to see if the string matches a language name.
+ Note - we rely upon the alpha-sorted nature of the entries in
+ the lang_names array, specifically that shorter names appear
+ before their longer variants. (i.e. C before C++). That way
+ when we are attempting to match --help=c for example we will
+ match with C first and not C++. */
+ for (i = 0, lang_flag = 0; i < cl_lang_count; i++)
+ if (strncasecmp (a, lang_names[i], len) == 0)
+ {
+ lang_flag = 1U << i;
+ break;
+ }
+
+ if (specific_flag != 0)
+ {
+ if (lang_flag == 0)
+ *pflags |= specific_flag;
+ else
+ {
+ /* The option's argument matches both the start of a
+ language name and the start of an option class name.
+ We have a special case for when the user has
+ specified "--help=c", but otherwise we have to issue
+ a warning. */
+ if (strncasecmp (a, "c", len) == 0)
+ *pflags |= lang_flag;
+ else
+ warning (0,
+ "--help argument %q.*s is ambiguous, "
+ "please be more specific",
+ len, a);
+ }
+ }
+ else if (lang_flag != 0)
+ *pflags |= lang_flag;
+ else
+ warning (0,
+ "unrecognized argument to --help= option: %q.*s",
+ len, a);
+
+ if (comma == NULL)
+ break;
+ a = comma + 1;
+ }
+
+ if (include_flags)
+ print_specific_help (include_flags, exclude_flags, 0, opts,
+ lang_mask);
+}
+
/* Handle target- and language-independent options. Return zero to
generate an "unknown option" message. Only options that need
extra handling need to be listed here; if you simply want
@@ -2119,131 +2258,7 @@ common_handle_option (struct gcc_options *opts,
case OPT__help_:
{
- const char *a = arg;
- unsigned int include_flags = 0;
- /* Note - by default we include undocumented options when listing
- specific classes. If you only want to see documented options
- then add ",^undocumented" to the --help= option. E.g.:
-
- --help=target,^undocumented */
- unsigned int exclude_flags = 0;
-
- if (lang_mask == CL_DRIVER)
- break;
-
- /* Walk along the argument string, parsing each word in turn.
- The format is:
- arg = [^]{word}[,{arg}]
- word = {optimizers|target|warnings|undocumented|
- params|common|<language>} */
- while (*a != 0)
- {
- static const struct
- {
- const char *string;
- unsigned int flag;
- }
- specifics[] =
- {
- { "optimizers", CL_OPTIMIZATION },
- { "target", CL_TARGET },
- { "warnings", CL_WARNING },
- { "undocumented", CL_UNDOCUMENTED },
- { "params", CL_PARAMS },
- { "joined", CL_JOINED },
- { "separate", CL_SEPARATE },
- { "common", CL_COMMON },
- { NULL, 0 }
- };
- unsigned int *pflags;
- const char *comma;
- unsigned int lang_flag, specific_flag;
- unsigned int len;
- unsigned int i;
-
- if (*a == '^')
- {
- ++a;
- if (*a == '\0')
- {
- error_at (loc, "missing argument to %qs", "--help=^");
- break;
- }
- pflags = &exclude_flags;
- }
- else
- pflags = &include_flags;
-
- comma = strchr (a, ',');
- if (comma == NULL)
- len = strlen (a);
- else
- len = comma - a;
- if (len == 0)
- {
- a = comma + 1;
- continue;
- }
-
- /* Check to see if the string matches an option class name. */
- for (i = 0, specific_flag = 0; specifics[i].string != NULL; i++)
- if (strncasecmp (a, specifics[i].string, len) == 0)
- {
- specific_flag = specifics[i].flag;
- break;
- }
-
- /* Check to see if the string matches a language name.
- Note - we rely upon the alpha-sorted nature of the entries in
- the lang_names array, specifically that shorter names appear
- before their longer variants. (i.e. C before C++). That way
- when we are attempting to match --help=c for example we will
- match with C first and not C++. */
- for (i = 0, lang_flag = 0; i < cl_lang_count; i++)
- if (strncasecmp (a, lang_names[i], len) == 0)
- {
- lang_flag = 1U << i;
- break;
- }
-
- if (specific_flag != 0)
- {
- if (lang_flag == 0)
- *pflags |= specific_flag;
- else
- {
- /* The option's argument matches both the start of a
- language name and the start of an option class name.
- We have a special case for when the user has
- specified "--help=c", but otherwise we have to issue
- a warning. */
- if (strncasecmp (a, "c", len) == 0)
- *pflags |= lang_flag;
- else
- warning_at (loc, 0,
- "--help argument %q.*s is ambiguous, "
- "please be more specific",
- len, a);
- }
- }
- else if (lang_flag != 0)
- *pflags |= lang_flag;
- else
- warning_at (loc, 0,
- "unrecognized argument to --help= option: %q.*s",
- len, a);
-
- if (comma == NULL)
- break;
- a = comma + 1;
- }
-
- if (include_flags)
- {
- target_option_override_hook ();
- print_specific_help (include_flags, exclude_flags, 0, opts,
- lang_mask);
- }
+ help_option_argument = arg;
opts->x_exit_after_options = true;
break;
}
diff --git a/gcc/opts.h b/gcc/opts.h
index f14d9bcb896..6e99eaddbaf 100644
--- a/gcc/opts.h
+++ b/gcc/opts.h
@@ -418,7 +418,8 @@ extern bool target_handle_option (struct gcc_options *opts,
void (*target_option_override_hook) (void));
extern void finish_options (struct gcc_options *opts,
struct gcc_options *opts_set,
- location_t loc);
+ location_t loc,
+ unsigned int lang_mask);
extern void default_options_optimization (struct gcc_options *opts,
struct gcc_options *opts_set,
struct cl_decoded_option *decoded_options,
--- cc_old.txt 2019-04-01 13:33:30.802779271 +0200
+++ cc.txt 2019-04-01 13:39:38.014353425 +0200
@@ -12,7 +12,7 @@
-Waggressive-loop-optimizations [enabled]
-Waliasing [disabled]
-Walign-commons [enabled]
- -Waligned-new=[none|global|all] none
+ -Waligned-new=[none|global|all] global
-Wall
-Walloc-size-larger-than= -1
-Walloc-zero [disabled]
@@ -35,9 +35,9 @@
-Wbuiltin-macro-redefined [enabled]
-Wc++-compat [disabled]
-Wc++0x-compat
- -Wc++11-compat [disabled]
- -Wc++14-compat [disabled]
- -Wc++17-compat [disabled]
+ -Wc++11-compat [enabled]
+ -Wc++14-compat [enabled]
+ -Wc++17-compat [enabled]
-Wc++1z-compat
-Wc-binding-type [disabled]
-Wc11-c2x-compat [enabled]
@@ -50,12 +50,12 @@
-Wcast-qual [disabled]
-Wcast-result [disabled]
-Wcatch-value
- -Wcatch-value=<0,3> 0
+ -Wcatch-value=<0,3> 1
-Wchar-subscripts [enabled]
-Wcharacter-truncation [disabled]
-Wchkp
-Wclass-conversion [enabled]
- -Wclass-memaccess [disabled]
+ -Wclass-memaccess [enabled]
-Wclobbered [enabled]
-Wcomment [enabled]
-Wcomments
@@ -71,9 +71,9 @@
-Wdate-time [disabled]
-Wdeclaration-after-statement [enabled]
-Wdelete-incomplete [enabled]
- -Wdelete-non-virtual-dtor [disabled]
+ -Wdelete-non-virtual-dtor [enabled]
-Wdeprecated [enabled]
- -Wdeprecated-copy [disabled]
+ -Wdeprecated-copy [enabled]
-Wdeprecated-copy-dtor [disabled]
-Wdeprecated-declarations [enabled]
-Wdesignated-init [enabled]
@@ -83,7 +83,7 @@
-Wdiv-by-zero [enabled]
-Wdo-subscript [disabled]
-Wdouble-promotion [disabled]
- -Wduplicate-decl-specifier [enabled]
+ -Wduplicate-decl-specifier [disabled]
-Wduplicated-branches [disabled]
-Wduplicated-cond [disabled]
-Weffc++ [disabled]
@@ -117,7 +117,7 @@
-Wif-not-aligned [enabled]
-Wignored-attributes [enabled]
-Wignored-qualifiers [enabled]
- -Wimplicit [enabled]
+ -Wimplicit [disabled]
-Wimplicit-fallthrough
-Wimplicit-fallthrough=<0,5> 3
-Wimplicit-function-declaration [enabled]
@@ -127,7 +127,7 @@
-Wincompatible-pointer-types [enabled]
-Winherited-variadic-ctor [enabled]
-Winit-list-lifetime [enabled]
- -Winit-self [disabled]
+ -Winit-self [enabled]
-Winline [disabled]
-Wint-conversion [enabled]
-Wint-in-bool-context [enabled]
@@ -153,7 +153,7 @@
-Wmemset-transposed-args [enabled]
-Wmisleading-indentation [enabled]
-Wmissing-attributes [enabled]
- -Wmissing-braces [enabled]
+ -Wmissing-braces [disabled]
-Wmissing-declarations [disabled]
-Wmissing-field-initializers [enabled]
-Wmissing-format-attribute
@@ -172,7 +172,7 @@
-Wno-alloca-larger-than
-Wno-vla-larger-than
-Wnoexcept [disabled]
- -Wnoexcept-type [disabled]
+ -Wnoexcept-type [enabled]
-Wnon-template-friend [enabled]
-Wnon-virtual-dtor [disabled]
-Wnonnull [enabled]
@@ -196,13 +196,13 @@
-Wpadded [disabled]
-Wparentheses [enabled]
-Wpedantic [disabled]
- -Wpessimizing-move [disabled]
+ -Wpessimizing-move [enabled]
-Wplacement-new
-Wplacement-new=<0,2> -1
-Wpmf-conversions [enabled]
- -Wpointer-arith [disabled]
+ -Wpointer-arith [enabled]
-Wpointer-compare [enabled]
- -Wpointer-sign [enabled]
+ -Wpointer-sign [disabled]
-Wpointer-to-int-cast [enabled]
-Wpragmas [enabled]
-Wprio-ctor-dtor [enabled]
@@ -213,9 +213,9 @@
-Wrealloc-lhs [disabled]
-Wrealloc-lhs-all [disabled]
-Wredundant-decls [disabled]
- -Wredundant-move [disabled]
+ -Wredundant-move [enabled]
-Wregister [disabled]
- -Wreorder [disabled]
+ -Wreorder [enabled]
-Wrestrict [enabled]
-Wreturn-local-addr [enabled]
-Wreturn-type [enabled]
@@ -295,7 +295,7 @@
-Wunused-but-set-parameter [enabled]
-Wunused-but-set-variable [enabled]
-Wunused-const-variable
- -Wunused-const-variable=<0,2> 1
+ -Wunused-const-variable=<0,2> 0
-Wunused-dummy-argument [disabled]
-Wunused-function [enabled]
-Wunused-label [enabled]
@@ -315,7 +315,7 @@
-Wvla [enabled]
-Wvla-larger-than=<number> -1
-Wvolatile-register-var [enabled]
- -Wwrite-strings [disabled]
+ -Wwrite-strings [enabled]
-Wzero-as-null-pointer-constant [disabled]
-Wzerotrip [disabled]
-frequire-return-statement [enabled]
--- fast.txt 2019-04-01 13:51:17.520773198 +0200
+++ fast_old.txt 2019-04-01 13:53:03.170950231 +0200
@@ -5,13 +5,13 @@
-Os
-faggressive-loop-optimizations [enabled]
-falign-functions [enabled]
- -falign-functions=
+ -falign-functions= 16
-falign-jumps [enabled]
- -falign-jumps=
+ -falign-jumps= 16:11:8
-falign-labels [enabled]
- -falign-labels=
+ -falign-labels= 0:0:8
-falign-loops [enabled]
- -falign-loops=
+ -falign-loops= 16:11:8
-fassociative-math [enabled]
-fassume-phsa [enabled]
-fasynchronous-unwind-tables [enabled]
@@ -126,7 +126,7 @@
-fprefetch-loop-arrays [enabled]
-fprintf-return-value [enabled]
-freciprocal-math [enabled]
- -freg-struct-return [disabled]
+ -freg-struct-return [enabled]
-frename-registers [enabled]
-freorder-blocks [enabled]
-freorder-blocks-algorithm=[simple|stc] stc
@@ -234,7 +234,7 @@
-funroll-loops [disabled]
-funsafe-math-optimizations [enabled]
-funswitch-loops [enabled]
- -funwind-tables [disabled]
+ -funwind-tables [enabled]
-fvar-tracking [enabled]
-fvar-tracking-assignments [enabled]
-fvar-tracking-assignments-toggle [disabled]
