[pushed] c++: Update value of __cplusplus for C++20.

[Jason Merrill via Gcc-patches]

It's past time to update this macro to the specified value for C++20.

libcpp/ChangeLog:

        * init.c (cpp_init_builtins): Update __cplusplus for C++20.
---
 libcpp/init.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libcpp/init.c b/libcpp/init.c
index f77dc26a003..7987798afbe 100644
--- a/libcpp/init.c
+++ b/libcpp/init.c
@@ -542,7 +542,7 @@ cpp_init_builtins (cpp_reader *pfile, int hosted)
     {
       if (CPP_OPTION (pfile, lang) == CLK_CXX20
          || CPP_OPTION (pfile, lang) == CLK_GNUCXX20)
-       _cpp_define_builtin (pfile, "__cplusplus 201709L");
+       _cpp_define_builtin (pfile, "__cplusplus 202002L");
       else if (CPP_OPTION (pfile, lang) == CLK_CXX17
          || CPP_OPTION (pfile, lang) == CLK_GNUCXX17)
        _cpp_define_builtin (pfile, "__cplusplus 201703L");

base-commit: 4f1d8bd5096cc234313b23f64cdac53a94ff75a2
-- 
2.27.0