Hi!
On Thu, Sep 14, 2017 at 11:28:09PM +0200, Jakub Jelinek wrote:
> > I'd be tempted to say leave all this, and march 1z -> 2a for the _next_
> > standard. 2020 or so is a good first stab at the date.
>
> I didn't want to add c++2a and gnu++2a in the same patch, it can be added
> incrementally and readd the above wording. Unless somebody else is planning
> to do that, I can do that next.
Here is so far untested incremental patch on top of the 1z -> 17 patch,
mostly using Andrew's patch, but adjusted so that it applies and with
various additions and small tweaks.
2017-09-15 Andrew Sutton <andrew.n.sut...@gmail.com>
Jakub Jelinek <ja...@redhat.com>
Add support for -std=c++2a.
* c-common.h (cxx_dialect): Add cxx2a as a dialect.
* opt.c: Add options for -std=c++2a and -std=gnu++2a.
* c-opts.c (set_std_cxx2a): New.
(c_common_handle_option): Set options when -std=c++2a is enabled.
(c_common_post_options): Adjust comments.
(set_std_cxx14, set_std_cxx17): Likewise.
* doc/cpp.texi (__cplusplus): Document value for -std=c++2a
or -std=gnu+2a.
* doc/invoke.texi: Document -std=c++2a and -std=gnu++2a.
* lib/target-supports.exp (check_effective_target_c++17): Return
1 also if check_effective_target_c++2a.
(check_effective_target_c++17_down): New.
(check_effective_target_c++2a_only): New.
(check_effective_target_c++2a): New.
* g++.dg/cpp2a/cplusplus.C: New.
* include/cpplib.h (c_lang): Add CXX2A and GNUCXX2A.
* init.c (lang_defaults): Add rows for CXX2A and GNUCXX2A.
(cpp_init_builtins): Set __cplusplus to 201709L for C++2a.
--- gcc/c-family/c-common.h.jj 2017-09-14 22:53:34.977313456 +0200
+++ gcc/c-family/c-common.h 2017-09-15 12:59:25.539053983 +0200
@@ -703,7 +703,9 @@ enum cxx_dialect {
/* C++14 */
cxx14,
/* C++17 */
- cxx17
+ cxx17,
+ /* C++2a (C++20?) */
+ cxx2a
};
/* The C++ dialect being used. C++98 is the default. */
--- gcc/c-family/c-opts.c.jj 2017-09-14 22:53:34.978313443 +0200
+++ gcc/c-family/c-opts.c 2017-09-15 14:28:21.287595277 +0200
@@ -111,6 +111,7 @@ static void set_std_cxx98 (int);
static void set_std_cxx11 (int);
static void set_std_cxx14 (int);
static void set_std_cxx17 (int);
+static void set_std_cxx2a (int);
static void set_std_c89 (int, int);
static void set_std_c99 (int);
static void set_std_c11 (int);
@@ -637,6 +638,12 @@ c_common_handle_option (size_t scode, co
set_std_cxx17 (code == OPT_std_c__17 /* ISO */);
break;
+ case OPT_std_c__2a:
+ case OPT_std_gnu__2a:
+ if (!preprocessing_asm_p)
+ set_std_cxx2a (code == OPT_std_c__2a /* ISO */);
+ break;
+
case OPT_std_c90:
case OPT_std_iso9899_199409:
if (!preprocessing_asm_p)
@@ -938,7 +945,7 @@ c_common_post_options (const char **pfil
warn_narrowing = 1;
/* Unless -f{,no-}ext-numeric-literals has been used explicitly,
- for -std=c++{11,14,17} default to -fno-ext-numeric-literals. */
+ for -std=c++{11,14,17,2a} default to -fno-ext-numeric-literals. */
if (flag_iso && !global_options_set.x_flag_ext_numeric_literals)
cpp_opts->ext_numeric_literals = 0;
}
@@ -1589,7 +1596,7 @@ set_std_cxx14 (int iso)
flag_no_gnu_keywords = iso;
flag_no_nonansi_builtin = iso;
flag_iso = iso;
- /* C++11 includes the C99 standard library. */
+ /* C++14 includes the C99 standard library. */
flag_isoc94 = 1;
flag_isoc99 = 1;
cxx_dialect = cxx14;
@@ -1604,7 +1611,7 @@ set_std_cxx17 (int iso)
flag_no_gnu_keywords = iso;
flag_no_nonansi_builtin = iso;
flag_iso = iso;
- /* C++11 includes the C99 standard library. */
+ /* C++17 includes the C11 standard library. */
flag_isoc94 = 1;
flag_isoc99 = 1;
flag_isoc11 = 1;
@@ -1612,6 +1619,22 @@ set_std_cxx17 (int iso)
lang_hooks.name = "GNU C++17";
}
+/* Set the C++ 202a draft standard (without GNU extensions if ISO). */
+static void
+set_std_cxx2a (int iso)
+{
+ cpp_set_lang (parse_in, iso ? CLK_CXX2A: CLK_GNUCXX2A);
+ flag_no_gnu_keywords = iso;
+ flag_no_nonansi_builtin = iso;
+ flag_iso = iso;
+ /* C++17 includes the C11 standard library. */
+ flag_isoc94 = 1;
+ flag_isoc99 = 1;
+ flag_isoc11 = 1;
+ cxx_dialect = cxx2a;
+ lang_hooks.name = "GNU C++17"; /* Pretend C++17 until standardization. */
+}
+
/* Args to -d specify what to dump. Silently ignore
unrecognized options; they may be aimed at toplev.c. */
static void
--- gcc/c-family/c.opt.jj 2017-09-14 22:53:34.977313456 +0200
+++ gcc/c-family/c.opt 2017-09-15 12:59:25.542053945 +0200
@@ -1932,6 +1932,10 @@ std=c++17
C++ ObjC++
Conform to the ISO 2017 C++ standard.
+std=c++2a
+C++ ObjC++
+Conform to the ISO 2020(?) C++ draft standard (experimental and incomplete
support).
+
std=c11
C ObjC
Conform to the ISO 2011 C standard.
@@ -1990,6 +1994,10 @@ std=gnu++17
C++ ObjC++
Conform to the ISO 2017 C++ standard with GNU extensions.
+std=gnu++2a
+C++ ObjC++
+Conform to the ISO 2020(?) C++ draft standard with GNU extensions
(experimental and incomplete support).
+
std=gnu11
C ObjC
Conform to the ISO 2011 C standard with GNU extensions.
--- gcc/doc/cpp.texi.jj 2017-09-14 22:53:34.000000000 +0200
+++ gcc/doc/cpp.texi 2017-09-15 14:23:32.394163061 +0200
@@ -1877,7 +1877,10 @@ selected, the value of the macro is
@code{199711L} for the 1998 C++ standard,
@code{201103L} for the 2011 C++ standard,
@code{201402L} for the 2014 C++ standard,
-@code{201703L} for the 2017 C++ standard.
+@code{201703L} for the 2017 C++ standard,
+or an unspecified value strictly larger than @code{201703L} for the
+experimental languages enabled by @option{-std=c++2a} and
+@option{-std=gnu++2a}.
@item __OBJC__
This macro is defined, with value 1, when the Objective-C compiler is in
--- gcc/doc/invoke.texi.jj 2017-09-15 14:21:24.861740328 +0200
+++ gcc/doc/invoke.texi 2017-09-15 14:22:04.607248773 +0200
@@ -1879,6 +1879,16 @@ The name @samp{c++1z} is deprecated.
@itemx gnu++1z
GNU dialect of @option{-std=c++17}.
The name @samp{gnu++1z} is deprecated.
+
+@item c++2a
+The next revision of the ISO C++ standard, tentatively planned for
+2020. Support is highly experimental, and will almost certainly
+change in incompatible ways in future releases.
+
+@item gnu++2a
+GNU dialect of @option{-std=c++2a}. Support is highly experimental,
+and will almost certainly change in incompatible ways in future
+releases.
@end table
@item -fgnu89-inline
--- gcc/testsuite/lib/target-supports.exp.jj 2017-09-14 22:53:35.000000000
+0200
+++ gcc/testsuite/lib/target-supports.exp 2017-09-15 14:34:44.232867697
+0200
@@ -7863,8 +7863,35 @@ proc check_effective_target_c++17_only {
}
return 0
}
+
proc check_effective_target_c++17 { } {
- return [check_effective_target_c++17_only]
+ if [check_effective_target_c++17_only] {
+ return 1
+ }
+ return [check_effective_target_c++2a]
+}
+proc check_effective_target_c++17_down { } {
+ if ![check_effective_target_c++] {
+ return 0
+ }
+ return [expr ![check_effective_target_c++2a] ]
+}
+
+proc check_effective_target_c++2a_only { } {
+ global cxx_default
+ if ![check_effective_target_c++] {
+ return 0
+ }
+ if [check-flags { { } { } { -std=c++2a -std=gnu++2a } }] {
+ return 1
+ }
+ if { $cxx_default == "c++20" && [check-flags { { } { } { } { -std=* } }] }
{
+ return 1
+ }
+ return 0
+}
+proc check_effective_target_c++2a { } {
+ return [check_effective_target_c++2a_only]
}
# Check for C++ Concepts TS support, i.e. -fconcepts flag.
--- gcc/testsuite/g++.dg/cpp2a/cplusplus.C.jj 2017-09-15 12:59:25.543053933
+0200
+++ gcc/testsuite/g++.dg/cpp2a/cplusplus.C 2017-09-15 12:59:25.543053933
+0200
@@ -0,0 +1,4 @@
+// { dg-do compile }
+// { dg-options "-std=c++2a" }
+
+static_assert(__cplusplus > 201703L);
--- libcpp/include/cpplib.h.jj 2017-09-15 12:59:25.544053920 +0200
+++ libcpp/include/cpplib.h 2017-09-15 13:01:03.516828002 +0200
@@ -171,7 +171,8 @@ enum cpp_ttype
enum c_lang {CLK_GNUC89 = 0, CLK_GNUC99, CLK_GNUC11,
CLK_STDC89, CLK_STDC94, CLK_STDC99, CLK_STDC11,
CLK_GNUCXX, CLK_CXX98, CLK_GNUCXX11, CLK_CXX11,
- CLK_GNUCXX14, CLK_CXX14, CLK_GNUCXX17, CLK_CXX17, CLK_ASM};
+ CLK_GNUCXX14, CLK_CXX14, CLK_GNUCXX17, CLK_CXX17,
+ CLK_GNUCXX2A, CLK_CXX2A, CLK_ASM};
/* Payload of a NUMBER, STRING, CHAR or COMMENT token. */
struct GTY(()) cpp_string {
--- libcpp/init.c.jj 2017-09-15 12:59:25.545053908 +0200
+++ libcpp/init.c 2017-09-15 13:00:43.267081384 +0200
@@ -110,6 +110,8 @@ static const struct lang_flags lang_defa
/* CXX14 */ { 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1,
1, 0 },
/* GNUCXX17 */ { 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1,
0, 1 },
/* CXX17 */ { 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
0, 1 },
+ /* GNUCXX2A */ { 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1,
0, 1 },
+ /* CXX2A */ { 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
0, 1 },
/* ASM */ { 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0 }
};
@@ -497,7 +499,10 @@ cpp_init_builtins (cpp_reader *pfile, in
if (CPP_OPTION (pfile, cplusplus))
{
- if (CPP_OPTION (pfile, lang) == CLK_CXX17
+ if (CPP_OPTION (pfile, lang) == CLK_CXX2A
+ || CPP_OPTION (pfile, lang) == CLK_GNUCXX2A)
+ _cpp_define_builtin (pfile, "__cplusplus 201709L");
+ else if (CPP_OPTION (pfile, lang) == CLK_CXX17
|| CPP_OPTION (pfile, lang) == CLK_GNUCXX17)
_cpp_define_builtin (pfile, "__cplusplus 201703L");
else if (CPP_OPTION (pfile, lang) == CLK_CXX14
Jakub
