It seems prudent to add C++26 now that the first C++26 papers have been
approved. I followed commit r11-6920 as well as r8-3237.
I was puzzled to see that -std=c++23 was marked Undocumented but
-std=c++2b wasn't. I think it should be the other way round, like
the earlier modes.
As for __cplusplus, I've arbitrarily chosen 202600L:
$ xg++ -std=c++26 -dM -E -x c++ - < /dev/null | grep cplusplus
#define __cplusplus 202600L
I've verified the patch with a simple test, exercising the new
directives. Don't forget to update your GXX_TESTSUITE_STDS!
This patch does not add -Wc++26-extensions.
Bootstrapped/regtested on x86_64-pc-linux-gnu, ok for trunk?
gcc/c-family/ChangeLog:
* c-common.h (cxx_dialect): Add cxx26 as a dialect.
* c-opts.cc (set_std_cxx26): New.
(c_common_handle_option): Set options when -std={c,gnu}++2{c,6} is
enabled.
(c_common_post_options): Adjust comments.
* c.opt: Add options for -std=c++26, std=c++2c, -std=gnu++26,
and -std=gnu++2c.
(std=c++2b): Mark as Undocumented.
(std=c++23): No longer Undocumented.
gcc/ChangeLog:
* doc/cpp.texi (__cplusplus): Document value for -std=c++26 and
-std=gnu++26.
* doc/invoke.texi: Document -std=c++26 and -std=gnu++26.
* dwarf2out.cc (highest_c_language): Handle GNU C++26.
(gen_compile_unit_die): Likewise.
libcpp/ChangeLog:
* include/cpplib.h (c_lang): Add CXX26 and GNUCXX26.
* init.cc (lang_defaults): Add rows for CXX26 and GNUCXX26.
(cpp_init_builtins): Set __cplusplus to 202600L for C++26.
gcc/testsuite/ChangeLog:
* lib/target-supports.exp (check_effective_target_c++23): Return
1 also if check_effective_target_c++26.
(check_effective_target_c++23_down): New.
(check_effective_target_c++26_only): New.
(check_effective_target_c++26): New.
* g++.dg/cpp26/cplusplus.C: New test.
---
gcc/c-family/c-common.h | 4 +++-
gcc/c-family/c-opts.cc | 28 +++++++++++++++++++++++-
gcc/c-family/c.opt | 24 +++++++++++++++++----
gcc/doc/cpp.texi | 5 +++++
gcc/doc/invoke.texi | 12 +++++++++++
gcc/dwarf2out.cc | 5 ++++-
gcc/testsuite/g++.dg/cpp26/cplusplus.C | 5 +++++
gcc/testsuite/lib/target-supports.exp | 30 +++++++++++++++++++++++++-
libcpp/include/cpplib.h | 2 +-
libcpp/init.cc | 13 ++++++++---
10 files changed, 116 insertions(+), 12 deletions(-)
create mode 100644 gcc/testsuite/g++.dg/cpp26/cplusplus.C
diff --git a/gcc/c-family/c-common.h b/gcc/c-family/c-common.h
index 336a09f4a40..b5ef5ff6b2c 100644
--- a/gcc/c-family/c-common.h
+++ b/gcc/c-family/c-common.h
@@ -740,7 +740,9 @@ enum cxx_dialect {
/* C++20 */
cxx20,
/* C++23 */
- cxx23
+ cxx23,
+ /* C++26 */
+ cxx26
};
/* The C++ dialect being used. C++98 is the default. */
diff --git a/gcc/c-family/c-opts.cc b/gcc/c-family/c-opts.cc
index c68a2a27469..af19140e382 100644
--- a/gcc/c-family/c-opts.cc
+++ b/gcc/c-family/c-opts.cc
@@ -111,6 +111,7 @@ static void set_std_cxx14 (int);
static void set_std_cxx17 (int);
static void set_std_cxx20 (int);
static void set_std_cxx23 (int);
+static void set_std_cxx26 (int);
static void set_std_c89 (int, int);
static void set_std_c99 (int);
static void set_std_c11 (int);
@@ -663,6 +664,12 @@ c_common_handle_option (size_t scode, const char *arg,
HOST_WIDE_INT value,
set_std_cxx23 (code == OPT_std_c__23 /* ISO */);
break;
+ case OPT_std_c__26:
+ case OPT_std_gnu__26:
+ if (!preprocessing_asm_p)
+ set_std_cxx26 (code == OPT_std_c__26 /* ISO */);
+ break;
+
case OPT_std_c90:
case OPT_std_iso9899_199409:
if (!preprocessing_asm_p)
@@ -1032,7 +1039,8 @@ c_common_post_options (const char **pfilename)
warn_narrowing = 1;
/* Unless -f{,no-}ext-numeric-literals has been used explicitly,
- for -std=c++{11,14,17,20,23} default to -fno-ext-numeric-literals. */
+ for -std=c++{11,14,17,20,23,26} default to
+ -fno-ext-numeric-literals. */
if (flag_iso && !OPTION_SET_P (flag_ext_numeric_literals))
cpp_opts->ext_numeric_literals = 0;
}
@@ -1820,6 +1828,24 @@ set_std_cxx23 (int iso)
lang_hooks.name = "GNU C++23";
}
+/* Set the C++ 2026 standard (without GNU extensions if ISO). */
+static void
+set_std_cxx26 (int iso)
+{
+ cpp_set_lang (parse_in, iso ? CLK_CXX26: CLK_GNUCXX26);
+ flag_no_gnu_keywords = iso;
+ flag_no_nonansi_builtin = iso;
+ flag_iso = iso;
+ /* C++26 includes the C11 standard library. */
+ flag_isoc94 = 1;
+ flag_isoc99 = 1;
+ flag_isoc11 = 1;
+ /* C++26 includes coroutines. */
+ flag_coroutines = true;
+ cxx_dialect = cxx26;
+ lang_hooks.name = "GNU C++26";
+}
+
/* Args to -d specify what to dump. Silently ignore
unrecognized options; they may be aimed at toplev.cc. */
static void
diff --git a/gcc/c-family/c.opt b/gcc/c-family/c.opt
index 0930a3c0422..bc03ebdad97 100644
--- a/gcc/c-family/c.opt
+++ b/gcc/c-family/c.opt
@@ -2403,13 +2403,21 @@ C++ ObjC++
Conform to the ISO 2020 C++ standard (experimental and incomplete support).
std=c++2b
-C++ ObjC++ Alias(std=c++23)
+C++ ObjC++ Alias(std=c++23) Undocumented
Conform to the ISO 2023 C++ draft standard (experimental and incomplete
support).
std=c++23
-C++ ObjC++ Undocumented
+C++ ObjC++
Conform to the ISO 2023 C++ draft standard (experimental and incomplete
support).
+std=c++2c
+C++ ObjC++ Alias(std=c++26) Undocumented
+Conform to the ISO 2026 C++ draft standard (experimental and incomplete
support).
+
+std=c++26
+C++ ObjC++
+Conform to the ISO 2026 C++ draft standard (experimental and incomplete
support).
+
std=c11
C ObjC
Conform to the ISO 2011 C standard.
@@ -2489,13 +2497,21 @@ C++ ObjC++
Conform to the ISO 2020 C++ standard with GNU extensions (experimental and
incomplete support).
std=gnu++2b
-C++ ObjC++ Alias(std=gnu++23)
+C++ ObjC++ Alias(std=gnu++23) Undocumented
Conform to the ISO 2023 C++ draft standard with GNU extensions (experimental
and incomplete support).
std=gnu++23
-C++ ObjC++ Undocumented
+C++ ObjC++
Conform to the ISO 2023 C++ draft standard with GNU extensions (experimental
and incomplete support).
+std=gnu++2c
+C++ ObjC++ Alias(std=gnu++26) Undocumented
+Conform to the ISO 2026 C++ draft standard with GNU extensions (experimental
and incomplete support).
+
+std=gnu++26
+C++ ObjC++
+Conform to the ISO 2026 C++ draft standard with GNU extensions (experimental
and incomplete support).
+
std=gnu11
C ObjC
Conform to the ISO 2011 C standard with GNU extensions.
diff --git a/gcc/doc/cpp.texi b/gcc/doc/cpp.texi
index b0a2ce3ac6b..e3e5d2af042 100644
--- a/gcc/doc/cpp.texi
+++ b/gcc/doc/cpp.texi
@@ -1911,6 +1911,11 @@ selected, the value of the macro is
or an unspecified value strictly larger than @code{202002L} for the
experimental languages enabled by @option{-std=c++23} and
@option{-std=gnu++23}.
+Similarly, the value of the macro is an unspecified value strictly
+larger than @code{202002L} (and at the same time strictly larger than
+the unspecified value defined for @option{-std=c++23} above) for the
+experimental languages enabled by @option{-std=c++26} and
+@option{-std=gnu++26}.
@item __OBJC__
This macro is defined, with value 1, when the Objective-C compiler is in
diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi
index fd4943bf317..efcf3bfb3d6 100644
--- a/gcc/doc/invoke.texi
+++ b/gcc/doc/invoke.texi
@@ -2507,6 +2507,18 @@ change in incompatible ways in future releases.
GNU dialect of @option{-std=c++2b}. Support is highly experimental,
and will almost certainly change in incompatible ways in future
releases.
+
+@item c++2c
+@itemx c++26
+The next revision of the ISO C++ standard, planned for
+2026. Support is highly experimental, and will almost certainly
+change in incompatible ways in future releases.
+
+@item gnu++2c
+@itemx gnu++26
+GNU dialect of @option{-std=c++2c}. Support is highly experimental,
+and will almost certainly change in incompatible ways in future
+releases.
@end table
@opindex aux-info
diff --git a/gcc/dwarf2out.cc b/gcc/dwarf2out.cc
index e70c47cec8d..9112fc0c64b 100644
--- a/gcc/dwarf2out.cc
+++ b/gcc/dwarf2out.cc
@@ -25105,6 +25105,8 @@ static char *producer_string;
static const char *
highest_c_language (const char *lang1, const char *lang2)
{
+ if (strcmp ("GNU C++26", lang1) == 0 || strcmp ("GNU C++26", lang2) == 0)
+ return "GNU C++26";
if (strcmp ("GNU C++23", lang1) == 0 || strcmp ("GNU C++23", lang2) == 0)
return "GNU C++23";
if (strcmp ("GNU C++20", lang1) == 0 || strcmp ("GNU C++20", lang2) == 0)
@@ -25215,7 +25217,8 @@ gen_compile_unit_die (const char *filename)
language = DW_LANG_C_plus_plus_14;
else if (strcmp (language_string, "GNU C++17") == 0
|| strcmp (language_string, "GNU C++20") == 0
- || strcmp (language_string, "GNU C++23") == 0)
+ || strcmp (language_string, "GNU C++23") == 0
+ || strcmp (language_string, "GNU C++26") == 0)
/* For now. */
language = DW_LANG_C_plus_plus_14;
}
diff --git a/gcc/testsuite/g++.dg/cpp26/cplusplus.C
b/gcc/testsuite/g++.dg/cpp26/cplusplus.C
new file mode 100644
index 00000000000..3027f9e711a
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp26/cplusplus.C
@@ -0,0 +1,5 @@
+// { dg-do compile }
+// { dg-options "-std=c++26" }
+
+// TODO: Update once __cplusplus is defined for C++23.
+static_assert(__cplusplus > 202002L);
diff --git a/gcc/testsuite/lib/target-supports.exp
b/gcc/testsuite/lib/target-supports.exp
index d79ad4be105..c04db2be7f9 100644
--- a/gcc/testsuite/lib/target-supports.exp
+++ b/gcc/testsuite/lib/target-supports.exp
@@ -10785,7 +10785,35 @@ proc check_effective_target_c++23_only { } {
return 0
}
proc check_effective_target_c++23 { } {
- return [check_effective_target_c++23_only]
+ if [check_effective_target_c++23_only] {
+ return 1
+ }
+ return [check_effective_target_c++26]
+}
+
+proc check_effective_target_c++23_down { } {
+ if ![check_effective_target_c++] {
+ return 0
+ }
+ return [expr ![check_effective_target_c++26] ]
+}
+
+proc check_effective_target_c++26_only { } {
+ global cxx_default
+ if ![check_effective_target_c++] {
+ return 0
+ }
+ if [check-flags { { } { } { -std=c++26 -std=gnu++26 -std=c++2c
-std=gnu++2c } }] {
+ return 1
+ }
+ if { $cxx_default == "c++26" && [check-flags { { } { } { } { -std=* } }] }
{
+ return 1
+ }
+ return 0
+}
+
+proc check_effective_target_c++26 { } {
+ return [check_effective_target_c++26_only]
}
# Check for C++ Concepts support, i.e. -fconcepts flag.
diff --git a/libcpp/include/cpplib.h b/libcpp/include/cpplib.h
index d326f5aa316..aef703f8111 100644
--- a/libcpp/include/cpplib.h
+++ b/libcpp/include/cpplib.h
@@ -174,7 +174,7 @@ enum c_lang {CLK_GNUC89 = 0, CLK_GNUC99, CLK_GNUC11,
CLK_GNUC17, CLK_GNUC2X,
CLK_GNUCXX, CLK_CXX98, CLK_GNUCXX11, CLK_CXX11,
CLK_GNUCXX14, CLK_CXX14, CLK_GNUCXX17, CLK_CXX17,
CLK_GNUCXX20, CLK_CXX20, CLK_GNUCXX23, CLK_CXX23,
- CLK_ASM};
+ CLK_GNUCXX26, CLK_CXX26, CLK_ASM};
/* Payload of a NUMBER, STRING, CHAR or COMMENT token. */
struct GTY(()) cpp_string {
diff --git a/libcpp/init.cc b/libcpp/init.cc
index c508f06112a..8ef8833e508 100644
--- a/libcpp/init.cc
+++ b/libcpp/init.cc
@@ -127,6 +127,8 @@ static const struct lang_flags lang_defaults[] =
/* CXX20 */ { 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
1, 0, 1, 1, 1, 0, 0, 0, 0, 0, 1 },
/* GNUCXX23 */ { 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1,
1, 0, 1, 1, 1, 0, 1, 1, 1, 1, 1 },
/* CXX23 */ { 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
1, 0, 1, 1, 1, 0, 1, 1, 1, 1, 1 },
+ /* GNUCXX26 */ { 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1,
1, 0, 1, 1, 1, 0, 1, 1, 1, 1, 1 },
+ /* CXX26 */ { 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
1, 0, 1, 1, 1, 0, 1, 1, 1, 1, 1 },
/* ASM */ { 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }
};
@@ -561,9 +563,14 @@ cpp_init_builtins (cpp_reader *pfile, int hosted)
if (CPP_OPTION (pfile, cplusplus))
{
- /* C++23 is not yet a standard. For now, use an invalid
- * year/month, 202100L, which is larger than 202002L. */
- if (CPP_OPTION (pfile, lang) == CLK_CXX23
+ /* C++26 is not yet a standard. For now, use an invalid
+ year/month, 202600L, which is larger than 202100L. */
+ if (CPP_OPTION (pfile, lang) == CLK_CXX26
+ || CPP_OPTION (pfile, lang) == CLK_GNUCXX26)
+ _cpp_define_builtin (pfile, "__cplusplus 202600L");
+ /* C++23 is not yet a standard, either. For now, use an invalid
+ year/month, 202100L, which is larger than 202002L. */
+ else if (CPP_OPTION (pfile, lang) == CLK_CXX23
|| CPP_OPTION (pfile, lang) == CLK_GNUCXX23)
_cpp_define_builtin (pfile, "__cplusplus 202100L");
else if (CPP_OPTION (pfile, lang) == CLK_CXX20
base-commit: 33ebb0dff9bb022f1e0709e0e73faabfc3df7931
--
2.41.0
